A Grauntian perspective A Grauntian perspective on contemporary British on contemporary British
mortalitymortality
Mike Murphy, London School of Economics
Prepared for symposium: Mortality Past and Present: Celebrating the 350th anniversary of the
publication of John Graunt's Bills of Mortality
Gresham College, Barnard's Inn Hall, London
29 November 2012
Graunt’s legacyGraunt’s legacy• Mortality analysis & Life tables• Sex differentials• Cause of death analysis• Trend analysis• Cause of death classification• Use of administrative data
Mortality analysis & Life tables: Mortality analysis & Life tables: Period Period life expectancy at birth by sexlife expectancy at birth by sex
Years of life expectancy gained by Years of life expectancy gained by age in subsequent decade, England age in subsequent decade, England
and Wales, based on ONS dataand Wales, based on ONS dataMalesMales FemalesFemales
Further expectation of life by age and Further expectation of life by age and year reached age, based on ONS datayear reached age, based on ONS data
MalesMales FemalesFemales
Sex differentialSex differential in period life in period life expectancy at birthexpectancy at birth
Cause of death analysis:Cause of death analysis: Data qualityData quality
" ... all dying thereof die so emaciated and lean (their Ulcers disappearing upon Death) that the Old-women Searchers after the mist of a cup of Ale, and the bribe of a two-groat fee, instead of one, given them, cannot tell whether this emaciation, or leanness were from a Phthisis, or from an Hectic Fever, Atrophy, &c or from an Infection of the Spermatick parts ... ".Graunt J. Natural and political observations mentioned in a following index, and made upon the Bills of Mortality. Facsimile edition. New York: Arno Press, 1975.
Leading causes of death by sex in Leading causes of death by sex in 2011 & 2001, England and Wales2011 & 2001, England and Wales
Early Epidemiological Early Epidemiological Transition?Transition?
14. The second observation is, that of the said 229,250 dying of all diseases, there died of acute diseases (the Plague excepted) but about 50,000 or 2/9 parts.
15. The third observation is, that of the said 229 thousand about 70 died of chronic diseases, which shews (as I conceive) the state and disposition of the country (including as well its food, as air) in reference to health, or rather to longevity ... the chronic diseases shew the ordinary temper of the place, so that upon the proportion of chronic diseases seems to hang the judgment of the fitness of the country for long life.Graunt J. Natural and political observations mentioned in a following index, and made
upon the Bills of Mortality
Leading causes of death by sex and Leading causes of death by sex and age group, England and Wales, 2009age group, England and Wales, 2009
Source: Office for National Statistics
MalesFemales
Age Group Leading causes
Deaths
% of Age
Group Deaths% of Age
Group
1-4Congenital malformations & chromosomal abnormalities 39 16% 34 14%Influenza and pneumonia 14 6% 15 6%
5-19 Land transport accidents 249 22% 80 13%Suicide and injury/poisoning of undetermined intent 100 9%
20-34 Suicide and injury/poisoning of undetermined intent 852 21% 215 12%Land transport accidents 536 13% 115 6%Accidental poisoning 393 10% 89 5%
35-49 Ischaemic heart diseases 1,456 13%Suicide and injury/poisoning of undetermined intent 1,304 11% 363 5%Cirrhosis and other diseases of liver 1,244 11% 602 9%Malignant neoplasms of breast 1,049 15%
50-64 Ischaemic heart diseases 6,531 20% 1,597 7%Malignant neoplasm of trachea, bronchus and lung 3,375 10% 2,536 11%Cirrhosis and other diseases of liver 1,919 6%Malignant neoplasms of breast 2,616 12%
65-79 Ischaemic heart diseases15,46
6 19% 7,394 12%Malignant neoplasm of trachea, bronchus and lung 8,449 10% 5,991 10%
80+ Ischaemic heart diseases17,89
4 17% 21,405 14%
Cerebrovascular diseases10,19
9 10% 20,686 13%Influenza and pneumonia 7,552 7%Dementia and Alzheimer's disease 13,935 9%
Data qualityData quality
10. In brief, when any dead body is found in England, no algebraist, or uncipherer of letters, can use more subtle suppositions and variety of conjectures to find out the demonstration, or cipher, than every common unconcerned person doth to find out the murderers, and that for ever, until it be done.Graunt J. Natural and political observations mentioned in a following index, and
made upon the Bills of Mortality
““There is only one cause of death There is only one cause of death at old ages ...”at old ages ...”
7. … in case a man of 75 years old died of a cough (of which had he been free, he might have possibly lived to ninety) I esteem it little error (as to many of our purposes) if this person be in the table of casualties, reckoned among the Aged and not placed under the title of Coughs. Graunt J. Natural and political observations mentioned in a following index, and made upon the Bills of Mortality
Population AgeingPopulation Ageing18. “In the foregoing observations we ventured to make a standard of the healthfulness of the air from the proportion of acute and epidemic diseases, and of the wholesomeness of the food from that of the chronic. Yet forasmuch as neither of them alone do shew the longevity of the inhabitants, we shall in the next place come to the more absolute standard, and correction of both, which is the proportion of the aged, viz. 15,757 to the total 229,250. That is of about 1 to 15 or 7 per cent.”
“… I conceive, that in countries subject to great epidemic sweeps men may live very long, but where the proportion of the chronic distempers is great, it is not likely to be so; because men being long sick, and always sickly, cannot live to any great age …”
Graunt J. Natural and political observations mentioned in a following index, and made upon the Bills of Mortality
Period life expectancy for men at Period life expectancy for men at 65: by NS-SEC, 1982 to 200665: by NS-SEC, 1982 to 2006
Source: Longitudinal Study, Office for National Statistics
NS-SEC Period Increase
1982-86
2002-06
Years Per cent
1 Higher managerial and professional
15.2 18.8 3.6 23.7
2 Lower managerial and professional
15.1 18.2 3.1 20.5
3 Intermediate 13.9 17.5 3.6 25.94 Small employers and own account workers
14.0 17.5 3.5 25.0
5 Lower supervisory and technical
13.4 16.4 3.0 22.4
6 Semi routine 12.9 15.6 2.7 20.97 Routine 12.9 15.3 2.4 18.6
An optimistic view of the future?An optimistic view of the future?
“In recent years, UK life expectancy at birth has been growing at a rate of around a year every five years. For males in the UK, it is the fastest growth in longevity anywhere in the world. If it carries on, British males could become the world’s longest-lived men a few years from now”Mosaic society: Complex changes in UK society bring with them policy challenges Professor Ian Diamond, Chief Executive, Economic and Social Research Council, 2007.
Life expectancy at birth, EU 2009Life expectancy at birth, EU 2009
MalesMales FemalesFemales
Source: WHO HFA Database
Life expectancy at age 65, EU 2009Life expectancy at age 65, EU 2009
MalesMales FemalesFemales
Source: WHO HFA Database
Expectations about life expectancyExpectations about life expectancyA Potential Decline in Life Expectancy in the United States in the 21st Century“as a result of the substantial rise in the prevalence of obesity and its life-shortening complications such as diabetes, life expectancy at birth and at older ages could level off or even decline within the first half of this century.” (p. 1142) S. J. Olshansky, D J. Passaro, R C. Hershow, J Layden, B A. Carnes, J Brody, L Hayflick, R N. Butler, D B. Allison, and D S. Ludwig.New England Journal of Medicine 352;11 March 17, 2005
Ageing populations: the challenges ahead“If the pace of increase in life expectancy in developed countries over the past two centuries continues through the 21st century, most babies born since 2000 … [in] countries with long life expectancies will celebrate their 100th birthdays..” (p. 1139)
Kaare Christensen, Gabriele Doblhammer, Roland Rau, James W VaupelLancet 2009; 374: 1196–1208.
Estimated & projected rate of improvement of Estimated & projected rate of improvement of SDR, England & Wales 1901-2050SDR, England & Wales 1901-2050
Source: Based on ONS data
Estimated annual rate of improvement (%) of Estimated annual rate of improvement (%) of ASMR, England & Wales 1920-2010ASMR, England & Wales 1920-2010
MalesMales FemalesFemales
Source: Based on HMD data
Hypothesised explanations for the Hypothesised explanations for the ‘Golden cohorts’ include:‘Golden cohorts’ include:
• Differences in smoking patterns between generations
• Better diet and environmental conditions during and after the Second World War
• Those born in periods of low birth rate facing less competition for resources as they age
• Benefits from the introduction in the late 1940s of the Welfare State
• Benefits from medical advances which have increasingly affected older people.
Karen Dunnell, 2008, Ageing and Mortality in the UK – National Statistician's Annual Article on the Population. Population Trends 134: 6-23, p. 19
Cohort life expectancy at birth by sexCohort life expectancy at birth by sex
86.7
55.1
7.5
72.5
11.0 12.4 11.1
0
10
20
30
40
50
60
70
80
90
100
Lung cancer(C33,C34)
Upperaereodig.Cancer
(C00-C15)
Othercancer
COPD (J40-J47,J67)
Otherrespiratory
Vasculardiseases(I00-I99)
Othermedical
In 2000, Smoking responsible for:In 2000, Smoking responsible for:
Source: Peto, Lopez, Boreham, Thun (2006)
29.4
5.49.5
18.4
6 6.83.9 4.5
9.5
28.6
12.5
24.521.2 19.8
0
5
10
15
20
25
30
35
Males Females
Percent of deaths in causes Distribution of smoking deaths by cause & sex, all ages (%)
Does smoking provide the best Does smoking provide the best
explanation for observed patterns?explanation for observed patterns?
• There is strong cohort effect for lung cancer (& smoking)
• Cohort approaches provide a better basis for:• elucidating role of smoking on deaths in England
and Wales• investigating cohort effects in adult mortality
• Analysis using 20th and 21st Century Mortality Database England and Wales of deaths by sex, age (35+ yrs) and cause of death in the period 1950-2007.
APC modelAPC modelTo estimate the role of changing patterns of smoking
overall on adult cohort mortality we use an APC formulated as:
For any cause of death
For details, see Carstensen, B. (2006). Age-period-cohort models for the Lexis diagram. Statistics in Medicine, 26:3018-3045.
Murphy, M. & Di Cesare, M. (2012) Use of an age-period-cohort model to reveal the impact of cigarette smoking on trends in twentieth-century adult cohort mortality in England and Wales. Population Studies, ISSN 0032-4728
pcaapc RRRRm
Model characteristicsModel characteristicsDemographically-informed model with constraints:
• Age-specific rates for reference cohort• Relative risk for cohort (RRc), incorporates linear
“drift” component, & constrained to value 1 for reference cohort
• Relative risk for time period (RRp), constrained to average value of 1 over fitting range (& has no linear trend)
• Age, period and cohort functions modelled as cubic splines
Age Period Cohort models for mortality: Age Period Cohort models for mortality: cohorts born 1885-1955, England and Wales cohorts born 1885-1955, England and Wales
The approachThe approach• Most variation can be accounted for by
age and cohort functions, i.e. the period function is approximately constant
• Users are often concerned with the interpretation of current trends, i.e. rates of change
APC – Lung CancerAPC – Lung Cancer
Co
ho
rt with
the
hig
he
st leve
ls (m
ale
s)
Co
ho
rt with
the
hig
he
st leve
ls (fe
ma
les)
Infle
ction
po
int
For For these causesthese causes, the model , the model
simplifies tosimplifies to
caapc RRm 1 since pRR
lcapcc
srapc mkm assume &
.,constantelyapproximatis where kkk cc
Annual percentage rate of change of Annual percentage rate of change of cohort relative risk for those born 1885-cohort relative risk for those born 1885-
1955, England and Wales1955, England and Wales
Annual change in cohort standardised Annual change in cohort standardised mortality rate for those born 1885-1955, mortality rate for those born 1885-1955,
England and WalesEngland and WalesMalesMales FemalesFemales
Regression of annual change of total cohort Regression of annual change of total cohort mortality on change of lung cancer cohort mortality on change of lung cancer cohort
mortality, actual and fitted values, for those mortality, actual and fitted values, for those born 1885-1955, England and Wales:born 1885-1955, England and Wales:
Conclusions: Improving mortality Conclusions: Improving mortality
in Britain in Twentieth centuryin Britain in Twentieth centuryRate of improvement increasing to present
level of just over 2% p.a. on averageLarge infant mortality improvements over
whole periodInitially little old age mortality improvement;
recently increases at these agesSmoking-related mortality has an major
contribution to explaining mortality change, both sex differentials and to cohort patterns
The future?
Thank youThank you
The final modelThe final modelWe argue that the first term is cyclical (see earlier) and the
second term is long-term monotonic (ETT), which we fit as a linear term leading to the final model for k:
With estimates
)()()( 0ccchdc
dkSDRch
dc
dSDR lclc
R2 Coefficient 1/Coefficient
Males 0.743 3.286 0.304
Females 0.764 4.636 0.216