burden of disease study · data sources mortality data were sourced from the national cause of...
TRANSCRIPT
Fatal Burden of Disease and Injury, 2004-2013
Yuejen Zhao
Xiaohua Zhang
Margaret Foley
Steven Guthridge
DEPARTMENT OF HEALTH
BURDEN OF DISEASE STUDYNORTHERN TERRITORY
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DEPARTMENT OF HEALTH
NORTHERN TERRITORY BURDEN OF DISEASE STUDYB
Acknowledgements
The authors are indebted to the Registry of Births, Deaths and Marriages for the routine provision of deaths data.
© Department of Health, Northern Territory 2016This publication is copyright. The information in this report may be freely copied and distributed for non-profit purposes such as study, research, health service management and public information subject to the inclusion of an acknowledgement of the source. Reproduction for other purposes requires the written permission of the Chief Executive of the Department of Health, Northern Territory.
Suggested citationZhao Y, Zhang X, Foley M, Guthridge S. Northern Territory burden of disease study: Fatal burden of disease and injury, 2004–2013. Department of Health, Darwin, 2016.
ISBN 978-0-9924437-0-2
An electronic version is available at: https://health.nt.gov.au/professionals/health-gains
General enquiries about this publication should be directed to: Director, Health Gains Planning,Department of HealthPO Box 40596, Casuarina, NT 0811
Phone: (08) 8985 8074Email: [email protected]
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NORTHERN TERRITORY BURDEN OF DISEASE STUDY 1
DEPARTMENT OF HEALTH
Summary .......................................................................................................................................................................................... 2Key findings ................................................................................................................................................................................... 2
Introduction ................................................................................................................................................................................. 4Previous burden of disease studies ..................................................................................................................................... 4Purpose of this report ............................................................................................................................................................... 4
Methods ............................................................................................................................................................................................ 5Data sources ................................................................................................................................................................................. 5Disease group classification ................................................................................................................................................... 5Years of life lost estimation .................................................................................................................................................... 5
Results ................................................................................................................................................................................................ 6Mortality ......................................................................................................................................................................................... 6Years of life lost ............................................................................................................................................................................ 7Years of life lost by cause of death ...................................................................................................................................... 9Years of life lost in comparison .......................................................................................................................................... 17Gap in years of life lost by Aboriginality ........................................................................................................................ 20Change in years of life lost through time ...................................................................................................................... 22Difference in years of life lost by remoteness, region and district ..................................................................... 26
Discussion ................................................................................................................................................................................... 28
Appendices ................................................................................................................................................................................ 30
References ................................................................................................................................................................................. 33
List of tables .............................................................................................................................................................................. 34
List of figures ........................................................................................................................................................................... 35
Selected Health Gains Planning publications ....................................................................................... 36
Contents
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DEPARTMENT OF HEALTH
NORTHERN TERRITORY BURDEN OF DISEASE STUDY
This report provides a comprehensive account of the fatal burden of disease and injury (BOD) for the Northern Territory (NT) in terms of deaths and years of life lost (YLLs). YLLs are a measure of the disease burden in a population as the result of premature death, with a count which is based on age at death and the World Health Organisation standard life expectancy. The report updates the two previous NT BOD studies by covering the period from 2004 to 2013. Underlying cause of death was classified using the BOD categories developed by Australian Institute of Health and Welfare. The report provides comparisons between the fatal BOD of NT and total Australian populations as well as a breakdown by demographic characteristics and BOD categories in a detailed analysis of the varied patterns of mortality by age, sex, Aboriginality and NT region. The results of this study will inform service development and planning.
Key findings
> Over the 10 years from 2004 to 2013, there were 9867 deaths registered for NT residents, corresponding to 311131 YLLs.
> YLL was high in ages 0-4 years (10% of the total YLLs) and low in ages 5-14 (2%), while the majority of YLLs (67%) occurred in those aged over 35 years.
> Males experienced a YLL rate 1.5 times higher than females.
> NT Aboriginal residents experienced more than half (57%) of total YLLs, which was more than twice their population share (27%).
> The YLL rate for the NT Aboriginal population aged 30-44 years was 8 times higher than the non-Aboriginal population in the same age group.
> The NT Aboriginal total age-standardised YLL rate was 3.4 times the NT non-Aboriginal rate.
> Age standardised YLL rate in the NT Aboriginal population was 58% higher than the national Aboriginal average, with males and females similar in the extent of excess.
> The age adjusted YLL rate for the NT non-Aboriginal population was 21% higher than the rate for Australia as a whole, with males showing greater excess than females (25% vs 5%).
> Cardiovascular disease and cancer each accounted for 20% of the total YLLs, followed by unintentional injury (14%) and intentional injury (10%). The fatal BOD was higher in males than in females for all the four leading causes.
Summary
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> In the NT Aboriginal population the leading cause of YLLs was cardiovascular disease followed by cancers, while in the non-Aboriginal population cancer has overtaken cardiovascular disease.
> Intentional and unintentional injuries combined accounted for one-quarter of the total YLLs for the total NT population and were higher in males than females (28% vs 19%).
> Injury, either intentional or unintentional, caused over half of the YLLs for the age groups between 5 and 34 years. Intentional injury was the leading cause in the Aboriginal population. Unintentional injury was much greater than intentional injury in the non-Aboriginal population.
> The age standardised rate of total YLL declined between 1999 and 2012 for both NT populations. Over time the gap in YLL rate between Aboriginal and non-Aboriginal populations appeared to have fallen in absolute terms. The relative rate ratio, however, remained substantial and was between 3.0 and 4.0.
> During the study period there was a marked decline in the YLL rate caused by cardiovascular disease, intentional injury and infectious diseases. Respiratory diseases also decreased for Aboriginal residents, as did cancers, diabetes, and infant and congenital conditions for non-Aboriginal residents.
> The YLL rate in remote areas was almost twice as high as in non-remote areas. Central Australia was 20% higher than the Top End. Among all the health districts, Darwin Rural had the highest YLL rate, followed by Barkly and Alice Springs Rural. Darwin Urban and Alice Springs Urban had the lowest YLL rates.
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DEPARTMENT OF HEALTH
NORTHERN TERRITORY BURDEN OF DISEASE STUDY
Introduction
Disease and injury impose a substantial burden on the population and health system in the Northern Territory (NT). Previous Australian and NT burden of disease and injury (BOD) studies indicated the NT had the highest BOD on a per capita basis among all jurisdictions.1-3 The latest NT study indicates that between 1999 and 2003, the BOD in the Aboriginal population was 3.57 times the national average, and non-Aboriginal population 1.22 times the national average, after adjustment for age structure of the population.3 BOD is measured in disability-adjusted life years (DALY), a composite measure that incorporates both years of life lost (YLL) due to premature death and years lived with disability due to morbidity.4 In the NT study of 1999-2003, YLL component contributed 43% of total DALY.3 This report focuses on the fatal burden.
Previous burden of disease studies
Since the first report in 1996, the World Health Organization has regularly published global BOD reports,5-7 which have provided the key platform for maintaining and developing DALY methodology. In Australia, the Australian Institute of Health and Welfare (AIHW) published the first BOD study in 1999.8 The University of Queensland and AIHW conducted the second Australian BOD study in 2006.1 The AIHW has recently completed the third Australian BOD study and in 2015 released the first two publications for the fatal BOD, one for general Australian population,9 and one for the Indigenous population.10 More recently the AIHW published full Australian and Indigenous BOD reports.11,12
In the NT, the first two BOD studies were undertaken for the periods 1994-1998 and 1999-2003 respectively 2,3 to align with the two national studies which used information from 1996 and 2003. It is timely to update the BOD information for the NT to allow comparison with the new national results and inform health care policy and support regional health service planning.
Purpose of this report
This is the first report of the third NT BOD study. The purpose of this report is to
> estimate YLL for NT Aboriginal and non-Aboriginal populations for two five-year periods of 2004-2008 and 2009-2013;
> assess changes in YLL over time;
> compare the NT results with the national averages; and
> analyse YLL by sex, age, Aboriginality, regions (Central Australia and Top End) and health districts (Alice Springs Rural, Alice Springs Urban, Barkly, Darwin Rural, Darwin Urban, East Arnhem and Katherine), to inform health service development and planning.
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Data sources
Mortality data were sourced from the national cause of death unit record files, which were managed by the Australian Bureau of Statistics (ABS) prior to 2006 and the Australian Coordinating Registry thereafter. The dataset contains all deaths registered by the Births, Deaths and Marriages registries for the NT residents. For rate calculation, the NT estimated resident population (ERP) data were obtained from ABS. All data sources included demographic breakdown by age, sex, Aboriginality, NT health district and region of residence.
The main analysis was for the deaths between 2004 and 2013, based on year of death registration. The time trend since 1999 was assessed using the actual year of death. Because the death registration data ending 31 December 2013 were unlikely to be complete for 2013 due to delays in death registration, the year 2013 was omitted in the time trend analysis.
Disease group classification
This study adopted the standard classification of the Australian BOD study9 to assign deaths into BOD disease groups, based on cause of death coded in International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Australian Modification (ICD-10). We subdivided injuries into intentional and unintentional injuries for the better addressing of the health issues in NT populations while still maintaining comparability with the national results.The BOD classification was generally based on the underlying cause of death. The original ABS mortality data contained multiple causes of death in alphabetical order. The multiple causes of each individual death were resequenced by the part (Part I first and Part II second) and duration between
onset and death (the longer duration, the higher priority). Thus, a death with ill-defined underlying cause was redistributed to the BOD group of the next classifiable cause in the sequence. If there was no classifiable sequential cause available, the redistribution was based on the proportions of classifiable deaths for the same ICD-10 chapter.
Years of life lost estimation
YLL was estimated using the standard life expectancy for the single year age at death sourced from the 2010 global BOD study.6 The standard life expectancy table was also used in the Australian BOD study.9 A death with age missing was assumed to be at the mean age of all deceased people of the same sex. The abridged lifetable was used to estimate life expectancies at birth by sex and Aboriginality.
Total YLL numbers and rates were analysed by key demographic, geographic and time variables. Because the NT has a younger age structure and a comparison of the NT crude rates with the counterparts of other states may be misleading, age was standardised directly13 using 2001 Australian ERP in line with the current Australian BOD study. Age-standardised YLL rates were used when comparing estimates by Aboriginality and between NT results and national figures, and to assess changes over time. Differences between populations based on the crude rates measures the actual gap, while the age-standardised rates measures the relative disparity after taking into account the younger age profile of the NT population. The ratio of age-standardised rates provides the relative gap in health between two populations. Standard deviations were derived using the bootstrap method.14 Sensitivity analyses were performed using either year of registration or year of death, and different BOD classifications.
Methods
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NORTHERN TERRITORY BURDEN OF DISEASE STUDY
Mortality
Between 1 January 2004 and 31 December 2013, there was a total of 9867 registered deaths of NT residents. Males accounted for 62% of total deaths; while the NT Aboriginal population accounted for 47% of deaths (Table 1), which was much greater than the population share (27%).15 The mean age at death was 51.4 years for Aboriginal and 66.6 years for non-Aboriginal residents.
Life expectancy at birth improved between 2004 and 2013 and the life expectancy gap between NT Aboriginal and non-Aboriginal populations narrowed slightly (Table 2). The life expectancy gaps by Aboriginality were greater for females (15.8 compared with 14.5 years in males in 2009-2013). Improvements in life expectancy between 2004-2008 and 2009-2013 were more marked in males in both NT Aboriginal and non-Aboriginal populations. More information on registered deaths is available in Appendices (Table A1).
Table 1. Deaths by age, sex and Aboriginality, Northern Territory, 2004-2013
2004-08 2009-13
Aboriginal Non-Aboriginal Aboriginal Non-Aboriginal
Age Female Male Female Male Female Male Female Male Total
0-4 56 87 29 32 55 69 30 28 386
5-9 8 4 5 5 8 6 0 4 40
10-14 8 13 2 5 10 10 5 5 58
15-19 17 43 9 19 16 35 7 14 160
20-24 26 62 14 38 26 59 8 40 273
25-29 33 64 9 35 30 45 9 48 273
30-34 47 87 12 43 25 73 9 20 316
35-39 71 127 11 48 63 92 18 46 476
40-44 79 120 26 70 91 109 17 44 556
45-49 84 124 38 101 90 119 46 82 684
50-54 86 110 54 119 119 138 36 130 792
55-59 96 94 53 185 99 111 58 168 864
60-64 74 90 57 197 80 117 69 186 870
65-69 73 91 62 187 90 92 79 215 889
70-74 78 62 61 203 97 84 82 221 888
75-79 66 49 95 198 69 50 82 194 803
80-84 51 23 104 134 45 28 98 191 674
85+ 48 32 171 120 60 33 236 165 865
Total 1001 1282 812 1739 1073 1270 889 1801 9867
Results
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Table 2. Life expectancy at birth (in years) by sex and Aboriginality, Northern Territory, 2004-2013
Aboriginal Non-Aboriginal Gap
Female Male Female Male Female Male
2004-2008 67.4 61.8 83.7 76.5 16.3 14.7
2009-2013 68.7 64.1 84.5 78.6 15.8 14.5
5-years increase 1.3 2.3 0.8 2.1 -0.5 -0.2
Years of life lost
There were 311131 YLLs due to premature deaths during the ten-year period between 2004 and 2013 (Table 3). Males were overrepresented making up 64% of the total YLLs, higher than the population proportion (52%). YLLs in Aboriginal people were also disproportionately higher (43%), relative to the population proportion (about 27%).15
For the overall population of NT, the contribution to the total YLL per age group at death was highest in ages 0-4 years (10%) and lowest in ages 5-14 years (<1.4%). Almost half of total YLLs (49%) occurred in those aged 35-64 years. The contribution by the ages less than 35 was much higher in Aboriginal people (49%) than in the non-Aboriginal people (29%). The opposite was true for the ages at death over 65 years (10% for Aboriginal and 28% for non-Aboriginal).
The total YLLs decreased by 3% between 2004-08 and 2009-13 periods. The decrease was apparent only in males (by 5%), especially in Aboriginal males (by 7%). The reduction in YLLs in ages less than 50 reflected a fall in deaths at younger ages. More information on YLLs is available in Appendices (Table A2).
As indicated in Figure 1, the YLL rate varies greatly with age. The YLL rate was 178 per 1000 population for the 0-4 age group, decreased to around 20 per 1000 for the 5-14 age groups and then increased with increasing age. This increase was gradual for ages 15-59 years before rising more rapidly with advancing age.
Males had a higher YLL rate than females in all age groups, except 5-9 years. The rate ratios between males and females were 0.9 in the 5-9 age group, but between 2 and 2.5 in the 15-34 years of age, and ranged from 1.2 to 1.8 in the other age groups (Figure 1).
The age specific YLL rates in the Aboriginal population were higher than those in non-Aboriginal population in all age groups (Figure 2). The ratios of age-specific YLL rates between populations ranged from 1.1 to 8.0, and were most marked in ages between 30 and 54 years with values over 5.5.
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NORTHERN TERRITORY BURDEN OF DISEASE STUDY8
Table 3. Years of life lost by age, sex and Aboriginality, Northern Territory, 2004-2013
2004-08 2009-13
Aboriginal Non-Aboriginal Aboriginal Non-Aboriginal
Age Female Male Female Male Female Male Female Male Total
0-4 4792 7299 2313 2490 4717 5900 2579 2390 32481
5-9 635 319 396 399 632 479 0 317 3177
10-14 586 959 150 369 735 737 371 367 4274
15-19 1184 2965 621 1295 1109 2422 484 955 11035
20-24 1672 4000 895 2439 1671 3798 513 2565 17552
25-29 1959 3782 530 2086 1789 2674 536 2864 16219
30-34 2557 4719 649 2347 1355 3955 486 1097 17166
35-39 3505 6300 540 2378 3110 4543 894 2262 23533
40-44 3535 5371 1160 3111 4061 4875 739 1973 24826
45-49 3359 4946 1517 4028 3581 4734 1828 3242 27235
50-54 3018 3865 1894 4168 4196 4875 1263 4568 27847
55-59 2933 2935 1676 5755 3012 3399 1776 5101 26587
60-64 1957 2357 1488 5106 2081 3046 1790 4828 22651
65-69 1567 1964 1346 4004 1954 1980 1695 4646 19156
70-74 1348 1074 1060 3489 1669 1474 1426 3805 15344
75-79 875 648 1261 2605 945 663 1083 2586 10666
80-84 487 217 1008 1344 438 284 933 1832 6544
85+ 277 176 924 688 355 193 1261 964 4838
Total 36246 53895 19429 48102 37409 50030 19657 46362 311131
Figure 1. Age specific years of life lost per 1000 population by sex, and male : female rate ratio, Northern Territory, 2004-2013
Year
s of l
ife lo
st p
er 1
000
Rat
e ra
tio
Age (years)
Male
Female
Rate ratio
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Figure 2. Age specific years of life lost per 1000 population and rate ratio by Aboriginality, Northern Territory, 2004-2013
Years of life lost by cause of death
Cardiovascular disease was the leading cause of YLLs, accounting for 20% of the total YLLs, followed by cancer (20%), unintentional injury (15%) and intentional injury (10%) (Table 4). If intentional and unintentional injuries are combined, injuries would be the number one cause of YLLs, responsible for one-quarter of total YLLs. Infant and congenital condition (7%) was the fifth cause of total YLLs, followed by gastrointestinal disease (6%).
Table 4 compares cause-specific YLLs by sex and Aboriginality. For the Aboriginal population the leading cause of YLLs was cardiovascular disease (21%), whereas the leading cause was cancer (29%) amongst the non-Aboriginal population. Intentional and unintentional injuries combined were responsible for 28% of total YLLs in males, similar for Aboriginal and non-Aboriginal populations.
Figures 3 and 4 show age distributions in the number and proportion of YLLs by causes of death for Aboriginal compared with non-Aboriginal populations. It is evident that YLLs in the 0-4 age group were dominated by infant and congenital conditions, particularly for Aboriginal children. In the age groups between 5 and 34 years, intentional and unintentional injuries accounted for the largest share of YLLs, peaking in the 15-19 age groups. Cardiovascular disease and cancer increase, as a proportion of all causes of YLLs for those aged 35 years and over, which together accounted over half (51%) of the total YLLs, more marked in the non-Aboriginal (58%) than Aboriginal population (45%). Diabetes, gastrointestinal, respiratory and kidney diseases together also accounted for a larger share (31%) in the Aboriginal population aged 35 years and over, while injuries combined attributed relatively more in non-Aboriginal population (16%).
Year
s of l
ife lo
st p
er 1
000
Rat
e ra
tio
Age (years)
Aboriginal
Non-Aboriginal
Rate ratio
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Figures 5 and 6 illustrate the top five leading causes of YLLs for each age, sex and Aboriginality stratum. There were major differences in the pattern of leading causes of YLLs between Aboriginal and non-Aboriginal populations.
Figure 7 compares YLL age distributions and age-specific YLL rates between males and females for the top four overall leading causes - cardiovascular disease, cancer, unintentional and intentional injury. The YLL rate for males was higher in most age groups than females for all the four causes.
Figure 8 shows that for the four leading causes of YLL, the age distribution of YLL was much younger and the age-specific YLL rates were, in general, substantially higher among Aboriginal compared with non-Aboriginal populations for those aged under 75, indicating that the Aboriginal population experienced these diseases and injuries at younger ages than the non-Aboriginal population.
Table 4. Years of life lost (rank in parentheses) by cause of death, sex and Aboriginality, Northern Territory, 2004-2013
Aboriginal Non-Aboriginal
Female Male Female Male Total
Cardiovascular 15031 (1) 22954 (1) 5798 (2) 18254 (2) 62037 (1)
Cancer 10352 (2) 12060 (4) 13130 (1) 25458 (1) 61000 (2)
Unint injury 8135 (3) 15463 (2) 5454 (3) 18007 (3) 47059 (3)
Int injury 5667 (6) 13784 (3) 1725 (7) 9088 (4) 30264 (4)
Infant 5886 (4) 8281 (5) 3237 (4) 3912 (7) 21316 (5)
Gastrointestinal 5864 (5) 5932 (6) 1649 (8) 4793 (6) 18239 (6)
Respiratory 3469 (10) 5716 (7) 1806 (6) 5027 (5) 16018 (7)
Infection 4171 (9) 4929 (8) 1011 (9) 2293 (9) 12403 (8)
Diabetes 4799 (7) 4535 (9) 728 (11) 2098 (10) 12161 (9)
Kidney 4667 (8) 3838 (10) 559 (12) 632 (13) 9696 (10)
Neurological 1704 (11) 3110 (11) 2124 (5) 2330 (8) 9269 (11)
Blood 1472 (12) 1113 (13) 963 (10) 1289 (11) 4836 (12)
Mental 856 (14) 1517 (12) 195 (14) 653 (12) 3221 (13)
Musculoskeletal 1098 (13) 495 (14) 454 (13) 423 (14) 2470 (14)
Skin 344 (15) 178 (15) 130 (15) 163 (15) 815 (15)
Maternal 139 (16) 9 (17) 119 (16) 43 (16) 311 (16)
Dental 0 (17) 10 (16) 5 (17) 0 (17) 15 (17)
Nervous 0 (18) 0 (18) 0 (18) 0 (18) 0 (18)
73655 103925 39086 94464 311131
Note: Unint=Unintentional; Int=Intentional
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Figure 3. Years of life lost and proportions by cause of deaths and 5-year age group, Aboriginal population, Northern Territory, 2004-2013
Note: Unint.=Unintentional; Int.=Intentional
Year
s of l
ife lo
st
Age (years)
Infant
Cancer
Diabetes
Cardiovascular
Mental
Neurological
Nervous
Respiratory
Gastrointestinal
Kidney
Maternal
Skin
Musculoskeletal
Dental
Blood
Unint injury
Int injury
Year
s of l
ife lo
st
Cancer
CardiovascularUnintentional injury
Intentional injury
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Figure 4. Years of life lost and proportions by cause of deaths and 5-year age group, non-Aboriginal population, Northern Territory, 2004-2013
Note: Unint.=Unintentional; Int.=Intentional
Year
s of l
ife lo
st
Age (years)
Infant
Cancer
Diabetes
Cardiovascular
Mental
Neurological
Nervous
Respiratory
Gastrointestinal
Kidney
Maternal
Skin
Musculoskeletal
Dental
Blood
Unint injury
Int injury
Year
s of l
ife lo
st
Cancer
CardiovascularUnintentional injury
Intentional injury
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15
Figure 7. Years of life lost and rates by age and sex, top four causes of years of life lost, Northern Territory, 2004-2013
Year
s of l
ife lo
stYe
ars o
f life
lost
Year
s of l
ife lo
stYe
ars o
f life
lost
Age (years)
Age (years)
Age (years)
Age (years)
Cardiovascular
Cancer
Unintentional injuries
Intentional injuries
Female
Rat
e pe
r 100
0R
ate
per 1
000
Rat
e pe
r 100
0R
ate
per 1
000
YLL
Rate
YLL
Rate
YLL
Rate
YLL
Rate
Year
s of l
ife lo
stYe
ars o
f life
lost
Year
s of l
ife lo
stYe
ars o
f life
lost
Age (years)
Age (years)
Age (years)
Age (years)
Cardiovascular
Cancer
Unintentional injuries
Intentional injuries
Male
Rat
e pe
r 100
0R
ate
per 1
000
Rat
e pe
r 100
0R
ate
per 1
000
YLL
Rate
YLL
Rate
YLL
Rate
YLL
Rate
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Figure 8. Years of life lost and rates by age and Aboriginality, top four causes of years of life lost, Northern Territory, 2004-2013
Year
s of l
ife lo
stYe
ars o
f life
lost
Year
s of l
ife lo
stYe
ars o
f life
lost
Age (years)
Age (years)
Age (years)
Age (years)
Cardiovascular
Cancer
Unintentional injuries
Intentional injuries
Aboriginal
Rat
e pe
r 100
0R
ate
per 1
000
Rat
e pe
r 100
0R
ate
per 1
000
YLL
Rate
YLL
Rate
YLL
Rate
YLL
Rate
Year
s of l
ife lo
stYe
ars o
f life
lost
Year
s of l
ife lo
stYe
ars o
f life
lost
Age (years)
Age (years)
Age (years)
Age (years)
Cardiovascular
Cancer
Unintentional injuries
Intentional injuries
Non-Aboriginal
Rat
e pe
r 100
0R
ate
per 1
000
Rat
e pe
r 100
0R
ate
per 1
000
YLL
Rate
YLL
Rate
YLL
Rate
YLL
Rate
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Years of life lost in comparison
Age-standardised rates of YLLs were used for the comparison between population groups. The ratio of age standardised YLL rates describes the relative disparity in fatal burden.
After controlling for age, the NT total YLL rate was 177.9 YLLs per 1000 population (Table 5), 86% higher than the national average.9 The NT Aboriginal YLL rate was 387.6 YLLs per 1000, 58% higher than the national Indigenous average10 and 4.06 times the Australian overall rate.9 The NT non-Aboriginal YLL rate was 115.7 YLLs per 1000, 23% higher than the Australian non-Indigenous population10 and 21% higher than the Australian general population.9 The NT overall age standardised Aboriginal to non-Aboriginal YLL rate ratio was 3.4, which was greater than the comparable national rate ratio of 2.6.10
After age standardisation, cancer was the leading cause of YLLs in the NT, cardiovascular disease was the second followed by unintentional and intentional injuries (Table 5). The NT Aboriginal cause-specific YLL rate was higher for every cause of death than the corresponding rates for their non-Aboriginal counterparts, with rate ratios ranging from the lowest 1.9 for cancer to the highest of 16.1 for kidney disease.
The highest age standardised YLL rate for the NT Aboriginal population was cardiovascular disease, which was 3.7 times the NT non-Aboriginal rate. Other comparative rate ratios, between NT Aboriginal and non-Aboriginal populations, include diabetes (9.3), mental disease (7.8), infections (5.8) and gastrointestinal disease (5.2). The rate ratios by Aboriginality were higher in NT than the nationwide rate ratios for all causes except unintentional injury.
Table 6 presents the age-standardised YLL rates by sex for the NT Aboriginal and non-Aboriginal populations during 2004-2013, compared with the Australian rates by sex in 2010.9 The overall rate in males was greater than in females, regardless of Aboriginality and same nationally. It is remarkable that the YLL rate in NT Aboriginal females was 4.5 times the national female average and the rate in NT Aboriginal males was 3.8 times the national average for males (Table 7). The YLL rates in NT non-Aboriginal by sex also exceeded the national averages 1.05 times for females and 1.25 times for males. The 95% Confident Interval (CI) of the YLL rate ratio indicates that the comparison with national figures was statistically significant in the Aboriginal population, males and females alike, and in non-Aboriginal males, but not in non-Aboriginal females.
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Table 5. Age-standardised years of life lost rate (per 1000 population) and rate ratio by Aboriginality and cause of death, Northern Territory 2004-2013 vs Australia 2010
Northern Territory Australia9
Total AboriginalNon-
AboriginalRate ratio
AboriginalNon-
AboriginalRate ratio
Cardiovascular 38.9 91.0 24.4 3.73 62.0 21.2 2.9
Cancer 40.8 66.4 34.5 1.92 55.8 32.4 1.7
Unint. Injury 20.5 34.6 15.2 2.28 17.9 7.6 2.4
Int. injury 12.7 25.1 6.6 3.80 15.5 5.0 3.1
Infant 7.9 12.4 4.6 2.72 8.4 4.5 1.9
Gastrointestinal 9.8 26.1 5.0 5.19 15.0 3.5 4.3
Respiratory 11.7 28.1 7.6 3.73 16.3 4.5 3.6
Diabetes 8.1 29.1 3.1 9.28 17.7 2.2 8.0
Infection 6.8 18.4 3.2 5.84 7.0 1.8 3.9
Kidney 6.4 26.2 1.6 16.07 10.0 1.5 6.7
Neurological 7.7 13.5 6.0 2.25 9.7 5.7 1.7
Mental 1.6 5.0 0.6 7.80 4.7 1.5 3.1
Blood 2.8 6.2 1.8 3.38 3.5 1.2 2.9
Musculoskeletal 1.6 3.5 1.0 3.55 1.6 0.6 2.7
Skin 0.6 1.4 0.3 4.03 0.7 0.2 3.5
Other groups* 0.2 0.5 0.1 4.02 0.2 0.1 3.0
Total 177.9 387.6 115.7 3.35 245.8 93.7 2.6
95%CI 177.1- 178.6
385.3- 389.9
115.2- 116.1
3.33-3.37
- - -
Notes: CI=confidence interval; Unint.=Unintentional; Int.=Intentional; intentional and unintentional split was based 2003 Australian burden of disease and injury study.16 *Other groups include maternal, dental and nervous disease groups.
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Table 6. Age-standardised years of life lost per 1000 population by sex and cause of death, Northern Territory 2004-2013 vs Australia 2010
Northern Territory Australia9
Aboriginal Non-Aboriginal
Female Male Female Male Female Male
Cardiovascular 71.8 112.2 14.9 32.5 15.3 27.9
Cancer 57.5 76.8 24.9 42.7 27.5 38.9
Unint. Injury 23.9 45.6 7.9 21.4 4.9 11.0
Int. injury 14.9 35.5 2.4 10.3 2.3 8.3
Infant 10.8 13.8 4.2 4.9 4.0 5.2
Gastrointestinal 26.4 25.3 2.9 6.8 2.7 4.7
Respiratory 21.9 35.2 4.8 10.2 3.8 5.7
Diabetes 28.9 29.2 1.9 4.1 1.9 3.0
Infection 16.9 20.1 2.0 4.1 1.5 2.3
Kidney 28.0 24.0 1.5 1.8 1.4 1.8
Neurological 11.0 15.9 5.7 6.1 5.1 6.0
Mental 3.7 6.4 0.4 0.9 0.8 2.3
Blood 5.9 6.9 1.7 1.9 1.1 1.4
Musculoskeletal 4.7 2.2 1.2 0.8 0.8 0.5
Skin 1.6 1.2 0.4 0.3 0.2 0.2
Other groups* 0.6 0.4 0.2 0.1 0.1 0.2
Total 328.7 450.8 76.9 148.9 73.4 119.4
95%CI 315.2- 342.2
433.8- 467.7
72.9- 81.0
143.9- 154.0
- -
Notes: Unint.=Unintentional; Int.=Intentional; Australian intentional and unintentional split was based 2003 study.16 *Other groups include maternal, dental and nervous disease groups.CI=Confidence interval derived by the Bootstrap method with 2000 replicates.
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Table 7. Age-standardised rate ratio by sex and cause of death, Northern Territory 2004-2013 vs Australia 2010
Aboriginal Non-Aboriginal
Female Male Female Male
Cardiovascular 4.69 4.02 0.98 1.17
Cancer 2.09 1.98 0.91 1.10
Unint. Injury 4.90 4.14 1.63 1.95
Int. injury 6.40 4.29 1.02 1.24
Infant 2.71 2.66 1.05 0.94
Gastrointestinal 9.79 5.38 1.09 1.44
Respiratory 5.76 6.18 1.26 1.78
Diabetes 15.24 9.73 1.01 1.37
Infection 11.28 8.75 1.31 1.78
Kidney 20.03 13.35 1.05 1.02
Neurological 2.17 2.66 1.12 1.01
Mental 4.68 2.78 0.45 0.40
Blood 5.35 4.90 1.53 1.36
Musculoskeletal 5.86 4.30 1.45 1.51
Skin 8.18 5.95 1.90 1.70
Other groups* 6.45 1.99 1.66 0.39
Total 4.48 3.78 1.05 1.25
95%CI 4.29-4.66 3.63-3.92 0.99-1.10 1.21-1.29
Notes: CI=Confidence interval derived by the Bootstrap method with 2000 replicates. Unint.=Unintentional; Int.=Intentional; Australian intentional and unintentional split was based 2003 study.16 * Other groups include maternal, dental and nervous disease groups.
Gap in years of life lost by Aboriginality
The gap in fatal burden is measured by the difference in age-standardised total YLL rates between two populations. Contributions by each cause to the gap inform the target areas for reducing the overall gap.
The NT Aboriginal population had a higher total YLL rate than their non-Aboriginal counterpart, with a gap of 271.9 YLL per 1000 population. The leading cause contributing to this gap was cardiovascular diseases, which was responsible for nearly one quarter (24%) of the difference (Table 8). This was followed by cancer, diabetes and kidney disease, each contributed around 10%. Intentional and unintentional injuries, when combined, claimed 14% of the total gap by Aboriginality.
Cancer, diabetes and kidney disease had higher contributions to the overall YLL gap by Aboriginality in females (Figure 9), while cardiovascular disease and injuries claimed greater responsibilities in males.
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Table 8. Age-standardised years of life lost rate (per 1000 population) and rate difference by Aboriginality and cause of death, Northern Territory, 2004-2013
RateRate
difference
Contribution to total rate
difference (%)Aboriginal Non-Aboriginal
Cardiovascular 91.0 24.4 66.6 24
Cancer 66.4 34.5 31.9 12
Unint. Injury 34.6 15.2 19.5 7
Int. injury 25.1 6.6 18.5 7
Infant 12.4 4.6 7.8 3
Gastrointestinal 26.1 5.0 21.0 8
Respiratory 28.1 7.6 20.5 8
Diabetes 29.1 3.1 26.0 10
Infection 18.4 3.2 15.3 6
Kidney 26.2 1.6 24.5 9
Neurological 13.5 6.0 7.5 3
Mental 5.0 0.6 4.4 2
Blood 6.2 1.8 4.4 2
Musculoskeletal 3.5 1.0 2.5 1
Skin 1.4 0.3 1.1 0
Other groups* 0.5 0.1 0.4 0
Total 387.6 115.7 271.9 100.0
Notes: Unint.=Unintentional; Int.=Intentional; *Other groups include maternal, dental and nervous disease groups.
Figure 9. Disease contributions by sex to the gap in age-standardised years of life lost rates between Aboriginal and non-Aboriginal populations, Northern Territory, 2004-2013
Notes: Unint.=Unintentional; Int.=Intentional
Cardiovascular 23%
Cancer 13%
Diabetes 11%Kidney
11%Gastrointestinal
9%
Respiratory 7%
Unint injury 6%
Infection 6%
Int injury 5%
Infant 3%
Neurological 2%
Cardiovascular 26%
Cancer 11%
Int injury8%Diabetes
8%Respiratory 8%
Unint injury 8%
Kidney 7%
Gastrointestinal 6%
Infection 5%
Neurological 3%Infant 3%
Female Male
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Change in years of life lost through time
Time trend analysis by year of death revealed that age-standardised YLL rate clearly declined over time in both Aboriginal and non-Aboriginal populations, with the rate of Aboriginal population constantly exceeding the non-Aboriginal rate (Figure 10). The difference in the age-standardised YLL rates between Aboriginal and non-Aboriginal populations decreased from 331 YLLs per 1000 population in 1999 to 285 in 2012. The rate ratio, however, remained relatively stable between 3.1 and 4.0, with no clear trend.
Based on the total number of YLLs in the three 5-year periods during 1999-2013, the rank of cancer, cardiovascular disease, unintentional and intentional injury as the top four causes remained unchanged in the non-Aboriginal population (Table 9).
For the Aboriginal population, cardiovascular disease remained the leading cause of YLLs throughout the three 5-year periods (Table 9). The second leading cause in the Aboriginal population was infant conditions in 1999-2003, replaced by unintentional injury in 2004-2008 and then by cancer in 2009-2013.
Cancer ranked at the fifth position in 1999-2003, but became the third in 2004-2008 and the second in 2009-2013. Unintentional and intentional injuries remained in the top four leading causes in the Aboriginal population over the three periods.
Tables 10 and 11 compare the age-standardised YLL rates by cause of death, Aboriginality and sex over the three periods. The age-standardised total YLL rates decreased over time for both Aboriginal and non-Aboriginal populations, and for both NT males and females. The reductions were more apparent for cardiovascular disease, especially in the Aboriginal population. The YLL rate of infections in the Aboriginal population decreased substantially, as did cancer in the non-Aboriginal population. There were also declines in cause-specific YLL rates in the Aboriginal population, for respiratory disease, intentional injury and infant conditions. Among NT residents the YLL rate of intentional injury in males, remained consistently higher than in females, but declined over the three periods. YLL rates for infant conditions also decreased for males.
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Table 9. Ranked causes for years of life lost by Aboriginality and cause of death, Northern Territory, 1999-2013
1999-03 2004-08 2009-13
AboriginalNon-
Aboriginal AboriginalNon-
Aboriginal AboriginalNon-
AboriginalCardiovascular 1 2 1 2 1 2
Cancer 5 1 3 1 2 1
Unint. Injury 4 3 2 3 3 3
Int. injury 3 4 4 4 4 4
Infant 2 5 5 6 5 5
Gastrointestinal 8 7 6 7 6 7
Respiratory 7 6 9 5 9 6
Infection 6 8 7 9 10 9
Diabetes 10 9 8 10 7 10
Kidney 9 13 10 12 8 12
Neurological 12 10 11 8 11 8
Blood 13 11 13 11 12 11
Mental 11 12 12 13 13 14
Musculoskeletal 14 14 14 14 14 13
Skin 16 15 15 15 15 16
Maternal 15 16 16 16 16 15
Dental 18 17 17 17 17 17
Nervous 17 18 18 18 18 18
Note: Unint.=Unintentional; Int.=Intentional.
Figure 10. Age-standardised years of life lost per 1000 population by Aboriginality, Northern Territory, 1999-2012
Year
s of l
ife lo
st p
er 1
000
Year
Aboriginal
Non-Aboriginal
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Table 10. Age-standardised years of life lost per 1000 by Aboriginality and cause of death, Northern Territory, 1999-2013
1999-03 2004-08 2009-13
AboriginalNon-
Aboriginal AboriginalNon-
Aboriginal AboriginalNon-
Aboriginal
Cardiovascular 120.7 33.7 99.9 28.5 83.6 21.3
Cancer 69.8 37.9 61.8 37.1 70.3 32.5
Unint. Injury 34.1 14.4 37.9 16.7 31.4 13.8
Int. injury 30.3 8.3 26.0 7.5 24.4 5.8
Infant 19.3 6.5 11.7 4.8 13.2 4.4
Gastrointestinal 22.0 5.0 29.2 5.8 23.2 4.4
Respiratory 33.9 7.9 29.2 8.6 27.2 6.8
Infection 28.8 4.6 24.9 3.8 12.9 2.7
Diabetes 29.8 3.5 32.1 3.9 26.8 2.6
Kidney 29.3 1.4 23.8 2.0 28.1 1.4
Neurological 12.2 3.7 13.2 5.4 13.8 6.4
Blood 7.5 2.3 6.3 2.1 6.0 1.6
Mental 10.3 1.5 6.2 0.7 4.0 0.6
Musculoskeletal 1.5 0.7 4.2 1.0 2.8 1.0
Skin 0.8 0.2 1.3 0.5 1.4 0.2
Maternal 1.1 0.1 0.7 0.1 0.2 0.1
Dental 0.0 0.0 0.2 0.0 0.0 0.0
Nervous 0.2 0.0 0.0 0.0 0.0 0.0
Total 451.6 131.7 408.5 128.4 369.4 105.7
5-year reduction - - 10% 3% 10% 18%
Note: Unint.=Unintentional; Int.=Intentional.
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Table 11. Age-standardised years of life lost per 1000 by sex and cause of death, Northern Territory residents, 1999-2013
1999-03 2004-08 2009-13
Female Male Female Male Female Male
Cardiovascular 39.4 61.8 32.4 54.6 25.5 43.3
Cancer 36.4 50.2 32.3 50.7 32.4 46.7
Unint. Injury 11.2 26.9 13.5 31.1 11.8 24.8
Int. injury 6.7 22.2 7.2 19.8 5.7 17.1
Infant 8.8 14.4 5.9 9.6 7.9 7.9
Gastrointestinal 7.1 10.2 9.0 13.2 8.1 8.9
Respiratory 10.2 16.0 8.7 16.1 8.5 13.3
Infection 9.0 11.5 7.4 10.1 4.1 5.9
Diabetes 8.8 8.5 8.8 9.8 7.2 7.2
Kidney 8.4 6.1 7.5 5.5 7.1 5.9
Neurological 5.4 5.7 6.9 7.6 7.1 8.9
Blood 3.1 3.4 3.2 2.8 2.5 2.7
Mental 1.7 5.1 1.4 2.5 1.0 1.7
Musculoskeletal 1.3 0.6 2.0 1.3 1.9 0.9
Skin 0.5 0.1 0.9 0.5 0.5 0.5
Maternal 0.7 0.0 0.3 0.2 0.3 0.0
Dental 0.0 0.0 0.0 0.1 0.0 0.0
Nervous 0.1 0.0 0.0 0.0 0.0 0.0
Total 158.6 242.7 147.3 235.6 131.5 195.5
5-year reduction - - 7% 3% 11% 17%
Note: Unint.=Unintentional; Int.=Intentional.
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Difference in years of life lost by remoteness, region and district
Figure 11 shows the different YLL rates by region and remoteness in the NT during the period 2004-2013. The age-standardised YLL rate of all residents was highest in remote Central Australia, followed closely by remote Top End. Non-remote Top End had the lowest YLL rate. The YLL rate in remote areas was almost twice as high as non-remote areas. The YLL rate in Central Australia was 20% higher on a per capita basis than the Top End (205 vs 171 YLLs per 1000 respectively).
At the level of health district, Darwin Rural had the highest YLL rate, followed by Barkly, Alice Springs Rural and East Arnhem (Figure 12). Darwin Urban and Alice Springs Urban had the lowest YLL rate among all the NT health districts.
Remoteness had an opposite effect on YLL rates for the NT Aboriginal and non-Aboriginal populations. The age-standardised YLL rate was lower in people living in remote area than those in non-remote area for the Aboriginal population, while it was the reverse for the non-Aboriginal population (Figure 13). This resulted in a greater gap of fatal burden by Aboriginality in non-remote area than in remote area, which is the reverse of national comparisons.10
Figure 11. Age-standardised years of life lost per 1000 by region and remoteness, Northern Territory, 2004-2013
Year
s of l
ife lo
st p
er 1
000
Region
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Figure 12. Age-standardised years of life lost per 1000 by district, Northern Territory, 2004-2013
Figure 13. Age-standardised years of life lost per 1000 and the gap between Aboriginal and non-Aboriginal populations, by remoteness, Northern Territory, 2004-2013
Year
s of l
ife lo
st p
er 1
000
District
Year
s of l
ife lo
st p
er 1
000
Aboriginal
Non-Aboriginal
Gap
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DEPARTMENT OF HEALTH
NORTHERN TERRITORY BURDEN OF DISEASE STUDY
This report describes the fatal BOD in the NT between 2004 and 2013. The fatal BOD was measured in YLLs by key demographics and underlying causes of death. The results update previous NT BOD reports and provide more accurate, robust and timely estimates for the NT. The report incorporates information over a longer period (two 5-year periods) than the national study (2009-2011) to minimise the fluctuation caused by the relatively smaller number of deaths in the NT. It uses the most up-to-date mortality data and applies the standard BOD methodology with classifications tailored for the NT health issues. It directly compares NT Aboriginal and non-Aboriginal populations as well as with national averages. The report also provides information on regional variation within the NT along with trends over time.
Because this study followed closely the methodology and classification of the current national BOD study,9,10 the results of this study are comparable to the 2009-2011 national estimates. However the results of this study should not be compared directly with previous NT and Australian BOD studies due to technical changes in the methods between studies including differences in cause classifications and standard life expectancies. A caution in interpreting age-standardised NT rates, based on the 2001 Australian ERP, is that the age-standardisation process increases the emphasis on causes of death that are related to older ages in the relatively young NT population. These are useful for comparison purposes but crude rates should be used for planning purposes. This report presents information on the fatal BOD, the burden associated with non-fatal conditions and the total BOD will be subject of subsequent reports.
The findings of this study provide a significant account of population ill-health which will inform health policy and planning health care services. This report highlights
> The higher fatal BOD in the NT than the national averages: Based on age-standardised rate ratios, the NT, as a whole, had an 1.86 times greater fatal burden than the Australian average. Within the NT, the Aboriginal population experienced a mortality burden, 3.4 times greater than the NT non-Aboriginal population.
> Besides the substantial gap between NT Aboriginal and non-Aboriginal population, NT non-Aboriginal males also had a higher YLL rate than the national average (NT : Australia rate ratio 1.25 in males vs 1.05 in females), with the greatest differences in unintentional injury and cardiovascular disease.
> Chronic diseases together account for 61% of the total difference in age-standardised YLL rates by Aboriginality. The key in reducing chronic disease mortality for the Aboriginal population lies in the combination of risk factor prevention, primary care and management for chronic diseases such as cardiovascular disease, cancers, diabetes and kidney disease.
> The gap in total YLL rates by Aboriginality is predominantly the result of deaths at relatively younger age in the Aboriginal population, including a greater burden in infant and congenital conditions as well as early onsets of preventable chronic diseases and deaths caused by the diseases.
> Intentional injuries, which mainly includes injuries from self-harm and assault, had a greater impact on the YLL of Aboriginal people. The YLL due to unintentional injuries from road traffic accidents, drug overdose, fires or falls were higher in the non-Aboriginal population, especially for males.
Discussion
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> In general the fatal burden was higher in the remote areas than the urban areas. More improvement is needed for the people living the remote areas in the NT.
> Noticeable improvements over time, in the NT, include YLLs from cardiovascular diseases, and infant and congenital diseases. YLLs from infectious diseases and respiratory diseases also decreased in the Aboriginal population. For the non-Aboriginal population reductions were also seen in cancers and intentional injuries. The areas requiring particular focus are gastrointestinal disease, kidney disease and unintentional injury for the whole NT population as well as cancers for the Aboriginal population.
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DEPARTMENT OF HEALTH
NORTHERN TERRITORY BURDEN OF DISEASE STUDY
Table A1. Number of registered deaths by Aboriginality and cause, Northern Territory, 2004-2013
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Aboriginal 449 454 452 461 467 432 447 437 539 488
Cardiovascular 123 117 104 109 92 95 97 117 122 100
Cancer 55 63 49 73 83 79 72 80 101 96
Unint. injury 43 40 54 43 53 43 42 29 54 43
Int. injury 33 30 29 44 32 26 37 35 42 29
Infant 18 16 22 14 11 17 22 16 16 16
Gastrointestinal 40 33 36 30 25 33 26 22 25 37
Respiratory 26 23 45 26 34 25 33 36 30 44
Infection 34 38 19 29 21 11 17 18 19 16
Diabetes 29 27 31 29 47 40 37 28 46 14
Kidney 18 18 28 32 30 27 24 25 38 60
Neurological 13 18 13 15 16 19 21 15 17 15
Blood 4 8 8 7 7 7 6 4 11 11
Mental 6 13 7 3 5 5 6 4 8 2
Musculoskeletal 4 4 3 4 8 1 5 3 7 2
Skin 2 2 1 1 1 2 0 4 1 2
Maternal 1 1 2 0 0 0 1 0 0 0
Dental 0 1 0 0 0 0 0 0 0 0
Nervous 0 0 0 0 0 0 0 0 0 0
Non-Aboriginal 438 519 480 540 574 522 534 527 499 608
Cardiovascular 124 114 118 124 128 112 110 110 117 136
Cancer 122 162 173 172 165 166 175 191 174 198
Unint. injury 38 58 41 58 74 54 64 48 40 59
Int. injury 33 24 20 31 24 22 26 21 29 18
Infant 8 10 6 10 11 9 9 8 8 11
Gastrointestinal 19 27 22 25 31 25 28 27 17 23
Respiratory 27 42 35 32 37 36 34 31 39 54
Infection 11 17 12 11 24 15 11 16 13 14
Diabetes 20 10 13 21 19 12 15 14 14 16
Kidney 4 9 7 11 9 12 9 4 7 8
Neurological 13 26 23 22 32 36 35 40 25 45
Appendices
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2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Blood 11 12 3 7 8 11 8 8 3 9
Mental 2 2 2 5 4 3 5 1 3 2
Musculoskeletal 2 4 3 8 4 6 3 2 7 9
Skin 2 3 2 2 1 0 1 2 1 3
Maternal 1 0 0 0 1 0 1 1 0 0
Dental 0 0 0 0 0 1 0 0 0 0
Nervous 0 0 0 0 0 0 0 0 0 0
Total 887 973 932 1001 1041 954 981 964 1038 1096
Note: Unint.=Unintentional; Int.=Intentional.
Table A2. Number of years of life lost by Aboriginality and cause, Northern Territory, 2004-2013
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Aboriginal 18149 18706 17768 18141 17378 16350 16589 16521 20812 17167
Cardiovascular 4421 4211 3592 4018 3143 3459 3291 4231 4404 3215
Cancer 1726 2017 1582 2332 2575 2297 2034 2130 3083 2636
Unint. injury 2269 2093 2868 2264 3007 2207 2069 1718 2857 2246
Int. injury 1896 1764 1665 2644 1808 1484 2050 2027 2438 1676
Infant 1476 1385 1815 1192 944 1377 1874 1353 1369 1381
Gastrointestinal 1776 1469 1355 1132 1014 1163 861 802 871 1355
Respiratory 638 881 1282 763 867 743 999 1002 714 1296
Infection 1591 1638 787 1079 858 381 555 736 824 651
Diabetes 802 818 851 819 1199 1164 1093 710 1492 387
Kidney 593 485 845 959 798 920 590 763 1156 1397
Neurological 282 657 371 440 483 599 556 386 661 380
Blood 178 339 271 229 198 269 166 176 388 371
Mental 232 631 288 90 149 183 218 206 290 87
Musculoskeletal 188 170 127 159 311 41 187 139 225 46
Skin 68 114 8 21 24 64 0 141 39 43
Maternal 14 25 61 0 1 0 46 1 1 0
Dental 0 10 0 0 0 0 0 0 0 0
Nervous 0 0 0 0 0 0 0 0 0 0
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2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Non-Aboriginal 12405 14314 12285 14198 14329 13052 13649 12800 12202 14317
Cardiovascular 2779 2436 2331 2284 2504 2192 2100 2031 2506 2889
Cancer 3040 3906 3875 4035 3591 3755 3874 4470 3761 4279
Unint. injury 1828 2695 1926 2522 3088 2327 3053 2076 1526 2420
Int. injury 1492 1090 896 1314 940 931 1113 921 1336 780
Infant 700 683 511 733 841 755 691 695 638 902
Gastrointestinal 450 753 742 746 700 707 703 631 490 521
Respiratory 603 857 675 780 743 627 535 466 713 835
Infection 253 440 318 243 578 402 169 280 256 364
Diabetes 428 218 227 455 351 175 271 216 262 224
Kidney 53 132 93 215 150 167 125 91 71 93
Neurological 268 469 440 337 502 482 575 558 408 416
Blood 332 442 103 142 155 263 197 169 82 367
Mental 57 26 72 187 125 94 116 29 80 61
Musculoskeletal 34 84 40 185 48 169 66 50 68 133
Skin 55 84 36 17 4 0 10 50 6 31
Maternal 32 1 0 0 10 0 53 66 0 0
Dental 0 0 0 0 0 5 0 0 0 0
Nervous 0 0 0 0 0 0 0 0 0 0
Total 30554 33020 30053 32338 31707 29402 30238 29321 33014 31484
Note: Unint.=Unintentional; Int.=Intentional.
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DEPARTMENT OF HEALTH
1. Begg S, Vos T, Barker B, Stevenson C, Stanley L, Lopez AD. The Burden of Disease and Injury in Australia 2003. Canberra: Australian Institute of Health and Welfare, 2007.
2. Zhao Y, Guthridge S, Magnus A, Vos T. Burden of disease and injury in Aboriginal and non-Aboriginal populations in the Northern Territory. Medical Journal of Australia 2004;180:498-503.
3. Zhao Y, You J, Guthridge S. Burden of disease and injury in the Northern Territory, 1999-2003. Darwin: Department of Health and Families, 2009.
4. Murray CJL, Lopez A. The global burden of disease : a comprehensive assessment of mortality and disability from diseases, injuries, and risk factors in 1990 and projected to 2020 World Health Organisation, 1996.
5. Mathers C, Fat DM, Boerma JT. The Global Burden of Disease: 2004 Update. Geneva: World Health Organization, 2008.
6. Murray CJ, Ezzati M, Flaxman AD, Lim S, Lozano R, Michaud C, et al. GBD 2010: design, definitions, and metrics. The Lancet 2012;380:2063-2066.
7. Vos T, Barber RM, Bell B, Bertozzi-Villa A, Biryukov S, Bolliger I, et al. Global, regional, and national incidence, prevalence, and years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013. The Lancet 2015.
8. Mathers C, Vos T, Stevenson C. The burden of disease and injury in Australia. Canberra: Australian Institute of Health and Welfare, 1999.
9. Australian Institute of Health and Welfare. Australian Burden of Disease Study: Fatal burden of disease 2010. Canberra: AIHW, 2015.
10. Australian Institute of Health and Welfare. Australian Burden of Disease Study: Fatal burden of disease in Aboriginal and Torres Strait Islander people 2010. Canberra: AIHW, 2015.
11. Australian Institute of Health and Welfare. Australian Burden of Disease Study: impact and causes of illness and death in Australia 2011. Canberra: AIHW, 2016.
12. Australian Institute of Health and Welfare. Australian Burden of Disease Study: Impact and causes of illness and death in Aboriginal and Torres Strait Islander people 2011. Canberra: AIHW, 2016.
13. Armitage P, Berry G, Matthews JNS. Statistical Methods in Medical Research Wiley, 2008.
14. Efron B, Tibshirani RJ. An Introduction to the Bootstrap. Florida: Taylor & Francis, 1994.
15. Australian Bureau of Statistics. 2011 Census QuickStats. http://www.abs.gov.au/websitedbs/censushome.nsf/home/quickstats?opendocument&navpos=220 Accessed June 3, 2015.
16. Vos DT, Barker B, Stanley L, Lopez A. The burden of disease and injury in Aboriginal and Torres Strait Islander peoples 2003 Centre for Burden of Disease and Cost-Effectiveness, School of Population Health, University of Queensland, 2007.
References
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List of tables
Table 1. Deaths by age, sex and Aboriginality, Northern Territory, 2004-2013 ................................. 6
Table 2. Life expectancy at birth (in years) by sex and Aboriginality, Northern Territory, 2004-2013................................................................................................................ 7
Table 3. Years of life lost by age, sex and Aboriginality, Northern Territory, 2004-2013 ............... 8
Table 4. Years of life lost (rank in parentheses) by cause of death, sex and Aboriginality, Northern Territory, 2004-2013............................................................................................................. 10
Table 5. Age-standardised years of life lost rate (per 1000 population) and rate ratio by Aboriginality and cause of death, Northern Territory 2004-2013 vs Australia 2010 ................................................................................................................ 18
Table 6. Age-standardised years of life lost per 1000 population by sex and cause of death, Northern Territory 2004-2013 vs Australia 2010 ............................. 19
Table 7. Age-standardised rate ratio by sex and cause of death, NT 2004-2013 vs Australia 2010 ......................................................................................................... 20
Table 8. Age-standardised years of life lost rate (per 1000 population) and rate difference by Aboriginality and cause of death, Northern Territory, 2004-2013 ......... 21
Table 9. Ranked causes for years of life lost by Aboriginality and cause of death, Northern Territory, 1999-2013............................................................................................................. 23
Table 10. Age-standardised years of life lost per 1000 by Aboriginality and cause of death, Northern Territory, 1999-2013 ......................................................................................... 24
Table 11. Age-standardised years of life lost per 1000 by sex and cause of death, Northern Territory residents, 1999-2013 ....................................................................................... 25
Table A1. Number of registered deaths by Aboriginality and cause, Northern Territory, 2004-2013............................................................................................................. 30
Table A2. Number of years of life lost by Aboriginality and cause, Northern Territory, 2004-2013 ....................................................................................................................................................... 31
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List of figures
Figure 1. Age specific years of life lost per 1000 population and male : female rate ratio by sex, Northern Territory, 2004-2013 ......................................................................... 8
Figure 2. Age specific years of life lost per 1000 population and rate ratio by Aboriginality, Northern Territory, 2004-2013................................................................................ 9
Figure 3. Years of life lost and proportions by cause of deaths and 5-year age group, Aboriginal population, Northern Territory, 2004-2013 .......................................................... 11
Figure 4. Years of life lost and proportions by cause of deaths and 5-year age group, non-Aboriginal population, Northern Territory, 2004-2013 ................................................ 12
Figure 5. Five leading cause of years of life lost by age and sex, Aboriginal population, Northern Territory, 2004-2013 .......................................................................................................... 13
Figure 6. Five leading cause of years of life lost by age and sex, non-Aboriginal population, Northern Territory, 2004-2013 ................................................................................ 14
Figure 7. Years of life lost and rates by age and sex, top four causes of years of life lost, Northern Territory, 2004-2013 ......................................................................................................... 15
Figure 8. Years of life lost and rates by age and Aboriginality, top four causes of years of life lost, Northern Territory, 2004-2013 .................................................................................. 16
Figure 9. Disease contributions by sex to the gap in age-standardised years of life lost rates between Aboriginal and non-Aboriginal populations, Northern Territory, 2004-2013 .......................................................................................................... 21
Figure 10. Age-standardised years of life lost per 1000 population by Aboriginality, Northern Territory, 1999-2012 .......................................................................................................... 23
Figure 11. Age-standardised years of life lost per 1000 by region and remoteness, Northern Territory, 2004-2013 .......................................................................................................... 26
Figure 12. Age-standardised years of life lost per 1000 by district, Northern Territory, 2004-2013 .......................................................................................................... 27
Figure 13. Age-standardised years of life lost per 1000 and the gap between Aboriginal and non-Aboriginal populations, by remoteness, Northern Territory, 2004-2013 .......................................................................................................... 27
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DEPARTMENT OF HEALTH
NORTHERN TERRITORY BURDEN OF DISEASE STUDY
Zhao Y, Guthridge S, Magnus A, Vos T. Burden of disease and injury in Aboriginal and non-Aboriginal populations in the Northern Territory. Med J Aust 2004, 180(10):498-502
You J, Guthridge S. Mortality, morbidity & health care costs of injury in the Northern Territory: 1991-2001. Darwin: Health Gains Planning, Department of Health and Community Services, 2005
Li SQ, Gray NJ, Guthridge SL, Pircher SLM. Avoidable mortality trends in Indigenous and non-Indigenous populations in the Northern Territory, 1985-2004. Aust NZ Public Health 2009;33:544-550
Zhao Y, You J, Guthridge S. Burden of disease and injury in the Northern Territory, 1999-2003. Darwin: Department of Health and Families, 2009
Skov J S, Chikritzhs N T, SQ Li, Pircher S, Whetton S. How much is too much? Alcohol consumption and related harms in the Northern Territory. Med J Aust 2010, 193(5): 269-272
Zhao Y, Malyon R. Cost drivers of remote clinics: remoteness and population size. Australian Health Review 2010; 34(1): 101-5
Zhao Y, Goss J, Malyon R. What drives health spending in the Northern Territory? Economic Papers 2010, 29(3): 292–300
Zhao Y, Condon JR, Guthridge S. Living Longer with a greater health burden –changes in the burden of disease and injury in the Northern Territory Indigenous population between 1994-1998 and 1999-2003. Aust NZ Public Health 2010(34) S93-S98
Zhao Y, Foley M, Eagar K. Assessing Economies of Scale in Public Hospitals. Economic Papers 2011, 30(3): 341-347
Zhao Y, You J, Guthridge SL, Lee AH. A multilevel analysis on the relationship between neighbourhood poverty and public hospital utilization: is the high Indigenous morbidity avoidable? BMC Public Health 2011, 11:737
Malyon R, Zhao Y, Oates B Differences in the cost of admitted patient care for Indigenous people and people from remote locations. Australian Health Review 2012, 37(1): 26-31
Foley M, Zhao Y, Condon J. Demographic Data Quality Assessment for Northern Territory Public Hospitals 2011. Darwin: Department of Health, 2012
Li SQ, Pircher SLM, Guthridge SL. Trends in alcohol-attributable hospitalisation in the Northern Territory,1998–99 to 2008–09. Med J Aust 2012, 197(6): 341-344
Zhao Y, Li SQ, Chikritzhs T. Alcohol-attributable deaths among indigenous and non-indigenous Australians. OA Alcohol 2013, 1(1):5
Zhao Y, Wright J, Begg S, Guthridge S. Decomposing Indigenous Life Expectancy Gap by Risk Factors: A Life Table Analysis. Population Health Metrics 2013, 11:1
Foley M, Zhao Y, You J, Skov S. Injuries in the Northern Territory 1997-2011, Department of Health, Darwin, 2015
Selected Health Gains Planning publications
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