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Dixon, J. B., Browne, J. L., Mosely, K. G., Rice, T. L., Jones, K. M., Pouwer, F. and Speight, J. 2013, Severe obesity and diabetes self-care attitudes, behaviours and burden: implications for weight management from a matched case-controlled study., Diabetic medicine, vol. 31, no. 2, pp. 232-240. This is the accepted manuscript. ©2013, The Authors This is the peer reviewed version of the article, which has been published in final form at http://dx.doi.org/10.1111/dme.12306. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Available from Deakin Research Online: http://hdl.handle.net/10536/DRO/DU:30058941

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This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1111/dme.12306 This article is protected by copyright. All rights reserved.

Received Date : 03-Apr-2013

Revised Date : 08-Jul-2013

Accepted Date : 12-Aug-2013

Article type : Research Article

Technical Editor DRH

Research: Educational and Psychological Aspects

Severe obesity and diabetes self-care attitudes, behaviours and burden: implications for weight management from a matched case-controlled study. Results from Diabetes MILES—Australia

J. B. Dixon1,2, J. L. Browne3,4, K. G. Mosely5, T. L. Rice1, K. M. Jones2, F. Pouwer6 and J.

Speight3,4,7

1Clinical Obesity Research, Baker IDI Heart and Diabetes Institute, 2School of Primary Health

Care, Faculty of Medicine, Nursing and Health Sciences, Monash University, 3The Australian

Centre for Behavioural Research in Diabetes, Diabetes Australia–Vic., 4Centre for Mental Health

and Wellbeing Research, School of Psychology, Deakin University, Melbourne, Vic., 5School of

Psychology, Australian Catholic University, Strathfield, NSW, Australia, 6Centre of Research on

Psychology in Somatic diseases (CoRPS), Department of Medical Psychology and

Neuropsychology, Tilburg University, Tilburg, The Netherlands and 7AHP Research,

Hornchurch, UK

Correspondence to: John Dixon. E-mail: [email protected]

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This article is protected by copyright. All rights reserved.

Running head: Severe obesity and diabetes—self-care attitudes, burdens and implications •

J. B. Dixon et al.

What’s new?

• This analysis demonstrates, for the first time, that severely obese and non-severely obese

(BMI < 35 kg/m2) individuals with Type 2 diabetes differ in their perceptions of diet,

physical activity and weight management.

• Despite more actively trying to lose weight, severely obese individuals placed less

importance in, and report greater burden with, diet and exercise recommendations.

• These differences appear weight-specific and not seen in other diabetes self-care

behaviours, including blood glucose monitoring or medication use.

• Awareness of this additional burden and specific support for weight management is

clearly needed to improve diabetes self-care outcomes for severely obese individuals.

Abstract

Aims To investigate whether diabetes self-care attitudes, behaviours and perceived burden,

particularly related to weight management, diet and physical activity, differ between adults with

Type 2 diabetes who are severely obese and matched non-severely obese control subjects.

Methods The 1795 respondents to the Diabetes MILES—Australia national survey had Type 2

diabetes and reported height and weight data, enabling BMI calculation: 530 (30%) were

severely obese (BMI ≥ 35 kg/m2; median BMI = 41.6 kg/m2) and these were matched with 530

control subjects (BMI < 35 kg/m2; median BMI = 28.2 kg/m2). Diabetes self-care behaviours,

attitudes and burden were measured with the Diabetes Self-Care Inventory—Revised. Within-

group and between-group trends were examined.

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Results The group with BMI ≥ 35 kg/m2 was less likely to achieve healthy diet and exercise

targets, placed less importance on diet and exercise recommendations, and found the burden of

diet and exercise recommendations to be greater than the group with BMI < 35 kg/m2. The group

with BMI ≥ 35 kg/m2 was more likely to be actively trying to lose weight, but found weight

control a greater burden. These issues accentuated with increasing obesity and were greatest in

those with BMI > 45 kg/m2. There were no between-group differences in other aspects of

diabetes self-care: self-monitoring of blood glucose, use of medications and smoking. Moderate-

to-severe symptoms of depression were independently associated with reduced likelihood of

healthy diet and physical activity, and with greater burden associated with diet, physical activity

and weight management.

Conclusions Severely obese people with diabetes demonstrated self-care attitudes, behaviours

and burdens that infer barriers to weight loss. However, other important diabetes self-care

behaviours are supported equally by severely obese and non-severely obese individuals.

Introduction

The general obesity pandemic, which spawned significant growth in the worldwide prevalence of

Type 2 diabetes [1], is now driving a disproportionate escalation of severe obesity in modern

society. A doubling of obesity prevalence leads to five- and 10-fold increases in those with a

BMI > 40 and 50 kg/m2, respectively [2]. The mean BMI for individuals with Type 2 diabetes in

the USA was 34.2 kg/m2 in 2006 [3], so severe obesity is clearly a significant issue in diabetes

management. Severe obesity (BMI > 35 kg/m2) and Type 2 diabetes are both common long-term

conditions requiring a chronic disease model of care to optimize health outcomes, a crucial

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element of which is enabling individuals to use self-care strategies to optimize their disease

management and improve health outcomes [4].

The landmark UK Prospective Diabetes Study demonstrated conclusively that the complications

of Type 2 diabetes can be prevented with sustained blood pressure and glycaemic control [5,6],

achieved primarily through rigorous self-care. The recommended self-care regimen for people

with Type 2 diabetes includes regular physical activity, healthy eating and attending regular

healthcare appointments, in addition to medication-taking, insulin use and self-monitoring of

blood glucose [7,8].

Weight management and associated self-care strategies for the severely obese may be

particularly challenging. Weight loss is generally modest (5–10%), variable, unsustainable and

programme retention rates are poor [9]. For many obese individuals, dieting is an extremely

common, lifelong behavioural strategy, requiring vigilance, imposing a significant personal

burden [10] and often resulting in repetitive weight regain [11]. Repeated perceived failure may

generate negative attitudes to unsuccessful behavioural change, and this may be reinforced by

stigmatization, a culture of blame and adverse experiences with health professionals [12].

Successful management of Type 2 diabetes and severe obesity therefore requires attention to the

behavioural, psychological and social aspects of these strongly associated conditions.

Previous research about frequency of, and barriers to, healthy eating and physical activity has

largely been undertaken with either an obese population or a population with diabetes, and not

specifically among those with co-morbid severe obesity and Type 2 diabetes. Furthermore, the

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perceived importance and burden of diabetes self-care and weight management behaviours, and

their associations with emotional well-being, among those with co-morbid severe obesity and

Type 2 diabetes, have not previously been examined.

Diabetes self-care is notoriously difficult to measure [13]. In general self-care measures assess

only the frequency with which particular health behaviours are performed [14]. A novel measure,

the Diabetes Self-Care Inventory—Revised (DSCI-R), assesses not only the frequency of the

behaviour, but also how important and how burdensome each behaviour is to the individual. The

DSCI-R is a modified version of a previously used self-care inventory [15]. Thus, this three-

pronged approach allows for a more comprehensive assessment of self-care: behaviours, beliefs

and burden.

Diabetes MILES—Australia (Management and Impact for Long-term Empowerment and

Success) was a national survey of adults with Type 1 and Type 2 diabetes, focused on the

psychosocial impact and behavioural aspects of living with these conditions [16]. The current

case-controlled analysis focused on a subset of participants with Type 2 diabetes (with and

without co-morbid severe obesity). Our aim was to examine a range of diabetes-specific self-care

behaviours, with particular focus on those that are also relevant to people who are severely obese

(BMI > 35 kg/m2)—healthy eating, physical activity and weight management. We sought to

describe the frequency with which these behaviours were performed, alongside perceptions of

their importance and burden. We also sought to characterize the subgroups that would be more or

less likely to engage in these behaviours, based on demographics, household income,

employment status and depressive symptoms.

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Subjects and methods

A detailed description of the study design and methods, including a full index of survey content

and detailed sample characteristics, has been published elsewhere [16]. A brief summary is

provided here.

Survey design and content

The survey focused on the topics of emotional well-being, self-management, health care and

support in relation to diabetes. It included a series of validated scales and study-specific items.

Data collection

The survey was made available in hard copy and online. Hard-copy survey booklets were posted

to 15 000 randomly selected National Diabetes Services Scheme (NDSS) registrants with Type 1

or Type 2 diabetes, aged 18–70 years. The online version was advertised nationally through

diabetes-specific media and in diabetes clinics. Diabetes MILES—Australia received ethical

approval from the Deakin University Human Research Ethics Committee (reference number

2011-046).

Participants

In total, 3338 eligible respondents took part in the Diabetes MILES—Australia 2011 survey; the

majority (70%; n = 2351) completed the postal survey [16]. Fifty-nine per cent of the sample

(n = 1941) had Type 2 diabetes (49% women; age 59 ± 9 years, 37% insulin-treated). The

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analysis reported here focuses on a subset of participants with Type 2 diabetes and co-morbid

severe obesity, defined as a BMI of ≥ 35 kg/m2. For this case-controlled analysis, each

participant with Type 2 diabetes and BMI ≥ 35 kg/m2 was carefully matched to one control

participant with Type 2 diabetes and BMI < 35 kg/m2 on the basis of age, gender, duration of

diabetes and use (or not) of insulin (Table 1). This matching allowed for confounding

differences between the groups to be minimized and, as each control participant was included

only once, this required selection from participants from those with a BMI < 35 kg/m2.

Data extracted for this analysis

The DSCI-R items relating to healthy eating, weight management and physical activity were the

main focus of this analysis; however, data relating to blood glucose monitoring, smoking and

medication-taking were also extracted for comparative purposes. For all behaviours, frequency

(‘How often do you…’) was assessed using a five-point Likert scale (never–almost always). The

only exception was ‘weight management’ (‘Are you trying to lose weight?’), which had a yes/no

response option. For all behaviours, perceived importance (‘How important is this for you?’) and

perceived burden (‘How much of a burden is this for you?’) were assessed using a four-point

Likert scale (importance: not at all–very; burden: not at all–a great burden).

Socio-demographic characteristics extracted from the database included marital relationship

status, living situation, education, household income and employment. In addition, as depression

is a common and significant confounding condition in Type 2 diabetes and obesity [17], the

Patient Health Questionnaire (PHQ-9) data were extracted. All items are scored with a total score

of ≥ 10 indicating moderate-to-severe depressive symptoms [18].

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Statistical methods

The analysis involved comparing case subjects with control subjects, and an examination of

increasingly severe obesity by stratifying the severely obese group into class II (BMI 35–

40 kg/m2), class IIIa (BMI 40–45 kg/m2) and class IIIb (BMI > 45 kg/m2) to assess relative

associations with increasing BMI.

Case subjects and control subjects were compared using χ2- tests for proportions, Student’s t-

tests for normally distributed outcomes (mean ± SD) or Mann–Whitney U-tests otherwise

(median ± interquartile range). Control subjects and the three levels of severe obesity were

compared using one-way analysis of variance (ANOVA) for normally distributed variables,

Kruskal–Wallis test for non-parametric continuous variables and linear association for

proportions.

Binary logistic regression analysis was used to identify factors independently associated with

binary grouped responses to DSCI-R questions regarding weight, diet and physical activity. All

variables of interest in the logistic regression were entered simultaneously (and confirmed with

forward and backward stepwise modelling) and those providing independent associations with

variance of each outcome response listed. SPSS statistical software version 18 (SPSS Inc.,

Chicago, IL, USA) was used for all analysis and a two-sided P-value of 0.05 was considered to

be statistically significant.

Results

The characteristics of the 1795 participants with Type 2 diabetes who reported their height and

weight (enabling BMI to be calculated) are shown in Table 1. The mean BMI for this cohort was

32.5 SD ± 7.9 kg/m2, and the median was 31.2 (interquartile range 27.4–36.2) kg/m2. Increasing

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BMI was associated with being female, younger and using oral hypoglycaemic agents or insulin

(all P < 0.001). Of these 1795 respondents, 530 (29.5%) were severely obese (BMI ≥ 35 kg/m2)

and the proportion of class III obese (BMI ≥ 40 kg/m2) was greater than the proportion of those

in the healthy weight range (BMI ≤ 25 kg/m2). Men (51.6%) were more highly represented in the

overweight category, but women comprised the majority in the BMI ≥ 35 and ≥ 40 kg/m2

categories (Table 1).

After carefully matching the 530 participants with a BMI ≥ 35 kg/m2 (case subjects) with 530

participants with a BMI < 35 kg/m2 (control subjects), there was no statistical difference between

the groups on any of the matching variables. Table 2 details the demographic, socio-economic,

clinical characteristics and co-morbidities of the control and case subjects (including

stratification by BMI). Increasing levels of obesity were associated with lower income, greater

likelihood of financial assistance ( unemployment and disability pension benefits) and increasing

levels of depression.

Weight management and healthy eating

In response to the DSCI-R questions about diet and managing weight, the severely obese

participants reported that they were less likely to be following a healthy diet, rated the

importance of dietary recommendations less highly and rated the burden of dietary

recommendations to be greater (Table 3). The differences were substantial: for example, 30% of

the non-severely obese control subjects ‘almost always’ followed a healthy diet, but only 18% in

the severely obese group and 12% in those with a BMI ≥ 45 kg/m2 did. However, over 90% of

the severely obese participants reported that they were currently trying to lose weight. While

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they reported the importance of weight management similarly to those in the control group, they

indicated it to be a greater burden (Table 3).

Physical activity

Severely obese respondents reported significant issues with physical activity and these issues

were accentuated with increasing obesity levels. They were less likely to achieve recommended

exercise guidelines, tended to place less importance on the value of exercise, found it a greater

burden and were more likely to report problems limiting physical activity (Table 3). The

differences were substantial: for example 30% of the non-severely obese control subjects

‘usually or almost always achieve 30 min of exercise 5 days of the week’, but only 16% in the

severely obese group and 7% in those with a BMI ≥ 45 kg/m2 did.

Findings are specific to healthy eating, weight management and physical activity

To test the specificity of the effects on healthy eating, weight management and physical activity,

we also examined two diabetes-specific self-care behaviours: self-monitoring of blood glucose

and taking oral medications to manage blood glucose. Data for those using self-monitoring and

taking oral medications are presented in Table 4. In addition, we investigated the DSCI-R issues

of using insulin as recommended, insulin adjustment, blood pressure medications, blood

cholesterol medications, smoking and feet inspections (data not shown). The respondents’

behaviours, and perceptions of the importance and burden associated with each of these

activities, was equivalent for case subjects and control subjects and did not alter with increasing

BMI, with the single exception of burden related to feet inspection which was greater with

increasing levels of obesity (P < 0.001).

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Discussion

On the one hand, this cross-sectional self-report survey of Australians living with Type 2

diabetes clearly demonstrates for the first time that, with increasing BMI, specific weight-

management-related behavioural and lifestyle issues of healthy eating, physical activity and

weight management are associated with attitudes, behaviours and perceived burden that infer

barriers to effective weight loss and diabetes self-care. On the other hand, responses to non-

weight-related diabetes self-care issues explored in the DSCI-R are not associated with different

responses among respondents who are severely obese. Thus, it is not self-care per se that appears

to be a problem in people with diabetes and severe obesity, but specifically the challenges

associated with weight management.

We can only speculate as to the reason for these responses. The responses related to burden are

understandable and those indicating disempowered attitudes and behaviours interesting. Several

hypotheses regarding causal and counter-causal relationships with severe obesity could be raised.

Were these different attitudes and behaviours inherent very early in life, and associated with

genetic, epigenetic and metabolic programming [19–20]? Did they develop during childhood,

adolescence or early adulthood, fashioned by family, peer-group, socio-demographic and

environmental factors [20]? Or have they developed in response to the burden and frustration of

living with the emerging problem of severe obesity [10]? All are plausible and all likely to

contribute directly or indirectly in some way. Kushner et al. have also described unhealthy

patterns of behaviour related to diet and exercise with increasing levels of obesity in a large

cross-sectional study [19]. Atlantis et al. have shown that Australians reporting higher weight

was associated with a reduced likelihood of achieving leisure time physical activity and fruit and

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vegetable consumption targets [21]. Whatever the aetiology, clinician understanding of these

attitudes, behaviours and burdens, together with knowledge of the physiological adaptations to

weight loss, are important for addressing the chronic and relapsing nature of severe obesity and

developing effective chronic disease management programmes [22]. A lack of empathy and

pejorative attitudes displayed by healthcare professionals, health service providers and payers,

and the broader community [‘patients are non-compliant, they lack willpower and control,

(obesity) is a lifestyle choice’] only perpetuate the ‘blame game’ that is so counterproductive in

delivering better health care [23].

It is very important to recognize that the severely obese group have the same self-management

characteristics as the control subjects for non-weight-related behavioural issues. This indicates

that they are not lazy, lacking willpower or uncaring about their health, and our findings do not

support a pejorative indifferent stereotype for these individuals. Indeed, health professionals

may focus on what their severely obese patients are doing well with other aspects of their

diabetes self-care to promote general health self-care.

Depression is an important factor associated with weight, diet and physical activity attitudes,

behaviours and burdens among those with Type 2 diabetes and severe obesity [24]. Gonzalez

et al. have demonstrated that diabetes self-care behaviours are negatively impacted by depression

and symptoms of depression [25]. Depression has positive reciprocal associations with obesity

in longitudinal studies [26]; is associated with unhealthy lifestyle and poorer weight loss in

several weight loss programmes [27]; and successful weight loss is associated with reduced

symptoms of depression [28]. We have previously described the compounding socio-

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demographic, emotional and health-related stressors in this group of severely obese people with

Type 2 diabetes [29]. Additionally, severe obesity and depression both have a major impact on

costs associated with managing diabetes [30]. Certainly, targeting depression and stress is an

important component of successful weight management programmes [26] and this is likely to be

even more crucial when managing co-morbid Type 2 diabetes.

Participants in this survey who reported low household income also reported less burden with

weight loss-related behaviours and were more likely to report healthy eating. This was not

altered when controlling for level of education and provided a novel and potentially important

finding. This may be explained by the relative importance of competing socio-demographic

stresses and burdens, or fewer insights into healthy practices, and need not imply greater success

with achieving behavioural targets. These findings appear counter-intuitive, and any implications

are unclear at this stage and require further investigation.

There are several important limitations to this study, many of which have been outlined

elsewhere [16]. It is a cross-sectional self-report survey including only those who volunteered to

take part. Therefore, data cannot be used to estimate population prevalence of the conditions

reported and we can only describe associations and not imply causality or counter-causality of

relationships. This study does, however, provide a snapshot of the characteristics of severely

obese individuals living with Type 2 diabetes, and provides a detailed picture of their self-

assessed health status, and their attitudes, behaviours and barriers to weight-related diabetes self-

care issues. Furthermore, we were conservative in adopting a control group of respondents with a

BMI up to 34 kg/m2, rather than including only those in the healthy BMI range, an approach

deemed appropriate given the matching requirements and relatively low proportion of

participants in the healthy weight range in the Diabetes MILES—Australia cohort.

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In conclusion, this study demonstrates that those living with Type 2 diabetes and severe obesity

report self-care attitudes, behaviours and barriers that infer specific barriers to effective weight

management or loss, but not to other important aspects of diabetes self-care. Of particular

concern is the combination of severe obesity and symptoms of moderate-to-severe depression. A

better understanding of these lifestyle-related diabetes self-management issues may assist in

providing non-judgemental and appropriate healthcare assessment, programmes and

interventions to improve long-term health outcomes.

Funding sources

The Diabetes MILES – Australia 2011 survey was funded by a National Diabetes Services

Scheme (NDSS) Strategic Development Grant. The NDSS is an initiative of the Australia

Government administered by Diabetes Australia. The Diabetes MILES Study is also supported

by an unrestricted educational grant from Sanofi-Aventis. The Royal Australian College of

General Practitioners provided support for this analysis (JBD and KMJ). None of the funding

bodies had any direct involvement in the conception, design or conduct of the analysis described

in this publication.

Competing interests

JBD receives a senior research fellowship from the Australian National Health and Medical

Research Council (NHMRC). JLB and JS receive research support through The Australian

Centre for Behavioural Research in Diabetes, a partnership for better health between Diabetes

Australia—Vic. and Deakin University. KGM, TLR, KMJ and FP have nothing to declare.

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Table 1 Characteristics of survey respondents* (n = 1795) by World Health Organization BMI category†

BMI category (kg/m2)

Total < 25 25 to < 30 30 to < 35 35 to < 40 ≥ 40

Total respondents (n) 1795 220 520 525 288 242

Percentage of total (%) 100 12.2 28.9 29.2 16.0 13.5

Male (%) 51.6 55.5 62.3 52.8 45.8 29.3

Age (mean ± SD) 58.4 ± 8.9 58.7 ± 8.7 60.2 ± 7.6 58.6 ± 8.4 56.7 ± 9.7 56.0 ± 8.7 Diabetes duration (years) (median ± interquartile range)

8 (3–12) 6 (3–11) 8 (3–12) 9 (4–13) 8.5 (4–12) 8 (4–13)

Age of Type 2 diabetes onset (years) (mean ± SD)

49.4 ± 9.7 50.8 ± 9.5 51.4 ± 9.2 49.2 ± 9.6 47.4 ± 9.7 46.6 ± 9.8

Using oral hypoglycaemic 73.9 60.5 71.9 74.7 78.8 82.6

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agents (%)

Using insulin (%) 36.7 21.4 30.6 40.4 45.1 45.9

*Respondents who reported having Type 2 diabetes and provided data regarding gender, age, height and weight.

†World Health Organization classifications.

Table 2 The demographic, socio-economic and clinical characteristics for control subjects and case subjects stratified by BMI subgroup

Matched control subjects

Case subjects

Subgroups of case subjects

Class II Class IIIa Class IIIb

BMI < 35 kg/m2

BMI ≥ 35 kg/m2

BMI 35 to < 40 kg/m2


BMI

≥ 45 kg/m2

P-value between groups*

P-value linear association†

Number of respondents

530 530 288 133 109

BMI (median) 28.2 41.6 37.1 42.0 49.1

Demographics

Age 56.6 ± 9.6

Median 58

56.4 ± 9.6

Median 58

56.7 ± 9.5

57.3 ± 9.4 54.4 ± 9.8 NA NA

Men (%) 38.3% 38.3% 46% 33.1% 24.8% NA NA

Unemployed 8.6% 9.0% 7.6% 4.6% 18.4% 0.80 0.002

Disability pension

14.9% 21.4% 16.5% 25.8% 28.7% 0.008 < 0.001

Private health insurance (hosp)

60.4% 49.6% 54.5% 44.0% 43.3% 0.001 < 0.001

Household income

≤ $A40 000

41.0% 50.6% 44.7% 59.0% 56.3% 0.003 0.001

Acc

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≥ $A100 000

18.2% 13.2% 18.7% 11.5% 2.9% 0.05 < 0.001

Diabetes characteristics

Duration of diabetes

8.8 ± 6.6

Median 8

9.2 ± 7.1

Median 8

9.2 ± 7.0 10 ± 7.5 8.4 ± 6.9 NA NA

Using insulin 45.5% 45.5% 45.1% 45.1% 46.8% NA NA

Primary therapy

Insulin 45.7% 45.8% 45.3% 45.5% 47.7%

NA

NA GLP-1 agonist

0.6% 2.1% 2.1% 2.3% 1.9%

Oral hypoglycaemic

agents

37.4% 42% 40.4% 47.0% 40.2%

Diet and exercise

16.3% 10.1% 12.3% 5.3% 10.3%

Depression

PHQ-9—total 5.0 (2–10)¶

6.0 (3–12) 6.0 (2.75–11)

7.0 (3–13)**

8.0 (3–13)**

< 0.001‡ < 0.001§

Moderate–severe (PHQ-9) depression symptoms

26.9% 36.8% 31.1% 43.2% 43.9% 0.001 < 0.001

NA, not applicable as these were the variables used to match the case subjects and the control subjects.

*P-values calculated by comparing case subjects’ and control subjects’ columns 2 and 3.

†Linear association using data columns 2 and 4–5.

‡§For Public Health Questionnaire (PHQ)-9 median (interquartile range, ‡ P-value from Kruskal–Wallis test and § P-value from ANOVA on loge transformed variable with values marked ¶ and ** as statistically significantly different.

Table 3 Responses to the Diabetes Self-Care (DSCI-R) diet, weight and physical activity questions

BMI < 35 kg/m

2

BMI ≥ 35 kg/m

2

BMI 35 to< 40 kg/m

2

BMI 40 to < 45 kg/m

2

BMI ≥�45 kg/m

2

P-value case vs.

control

P-valuecontrol group and

subgroups

Acc

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530 530 288 133 109


Casesubjects



Median BMI 28.2 41.6 37.1 42.0 49.1

Dietary and weight issues

How often do you follow a healthy diet?

Never 1.2% 2.7% 2.1% 3.8% 2.9%

Sometimes 17.7% 26.7% 28.3% 29.2% 34.0%

Regularly 27.6% 29.7% 29.8% 30.8% 32.0%

Often 23.2 21.1% 23.2% 17.7% 19.4%

(Almost) always 30.4% 17.7% 19.6 18.5% 11.7% < 0.001

< 0.001

Importance of dietary recommendations?

Not at all 1.2% 2.1% 1.8% 3.0% 1.9%

Somewhat 16.6% 22.1% 20.4% 25% 22.9%

Considerable 35.3% 43.1% 44.3% 38.6% 45.7%

Very 45.9% 32.7% 33.6% 33.3% 29.5% < 0.001

< 0.001

Level of burden with dietary recommendations?

Not at all 29.8% 23.2% 24.3% 22.7% 21.0%

Somewhat 42.8% 39.8% 42.9% 37.1% 35.2%

Acc

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Considerable 18.5% 25.9% 25.0% 27.3% 26.7%

A great burden 8.9% 11% 7.9% 12.9% 17.1% 0.08 < 0.001

Are you trying to lose weight?—‘Yes’

68.3% 93.2% 94.3% 90.6% 93.5% < 0.001

< 0.001

How important is weight to you?

Not at all 1.5% 1.9% 1.0% 3.0% 2.8% Somewhat 13.3% 11.9% 13.2% 10.6% 10.1% Considerable 26.2% 30.6% 32.6% 25.8% 31.2% Very 59.0% 55.6% 53.1% 60.6% 56% 0.394 0.841How much of a burden is weight to you?

Not at all 26.1% 16.0% 16.5% 15.9% 14.8%

Somewhat 38.9% 26.1% 26.8% 26.5% 32.5%

Considerable 20.6% 30.7% 31.3% 29.5% 30.6%

A great burden 14.3% 27.1% 25.4% 28.0% 30.6% < 0.001

< 0.001

Exercise 30 min 5 days per week: how often do you achieve this?

Never 14.2% 25% 19.9% 28.6% 33.9%

Sometimes 38.1% 42.2% 44.8% 38.3% 40.4%

Regularly 18.0% 16.7% 16.4% 15.8% 18.3%

Often 12.3% 8.9% 11.5% 8.3% 2.8%

(Almost) always 17.3% 7.2% 7.3% 9.0% 4.6% < 0.001

< 0.001

How important is exercise for you?

Not at all 3.1% 3.1% 2.5% 2.3% 5.6%

Somewhat 26.0% 29.7% 27.6% 29.8% 35.2%

Considerably 31.0% 35.1% 36.4% 36.6% 29.6%

Acc

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Very 40% 32.2% 33.6% 31.35 29.6% 0.073 0.006

How much of a burden is exercise for you?

Not at all 28.1% 16.1% 16.5% 15.3% 15.7% Somewhat 38.9% 33.5% 35.6% 33.6% 27.8% Considerably 20.4% 27.7% 28.9% 24.4% 28.7% A great burden 12.6% 22.8% 19.0% 26.7% 27.8% < 0.00

1 < 0.001

Do you have problems that limit physical activity?

50.2% 65.7% 63.0% 66.7% 71.7% < 0.001

< 0.001

Table 4 Responses to the Diabetes Self-Care (DSCI-R) questions pertaining to blood glucose and use of prescription tablets to lower blood glucose

BMI < 35 kg/m2

BMI ≥ 35 kg/m2

BMI 35 -< 40 kg/m2


BMI ≥ 45 kg/m2

P-value case vs.

control

P-valuecontrol group

and subgroups

Number of respondents

530 530 288 133 109


Casesubjects



Median BMI 28.2 41.6 37.1 42.0 49.1

How often do you measure your blood glucose per week? Mean/median

12.6/10 12.4/10 11.4/7.5 13.2/14 13.9/14 0.69* 0.09*

How important

Acc

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is it for you to measure your blood glucose levels? Not at all 5.3% 3.7% 4.1% 2.4% 4%

Somewhat 20.8% 25.7% 28.2% 24.4% 20.8%

Considerable 28.1% 26.5% 25.6% 25.2% 39.7%

Very 45.8% 44.1% 42.1% 48% 44.6% 0.56 0.86

How much of a burden is measuring blood glucose?

Not at all 45.1% 50.6% 49.6% 54.5% 48.5%

Somewhat 35.2% 35.5% 36.5% 30.9% 38.6%

Considerably 12.8% 10% 10.5% 10.6% 7.9%

A great burden 6.9% 3.9% 3.4% 4.1% 5.0% 0.06 0.03†

Do you take the prescribed number of tablets to lower your blood glucose level?

Never or sometimes

3.9% 4.2% 4.7% 3.5% 3.3%

Regularly or often

16.8% 18.6% 16.7% 21% 20.5%

Almost always 79.3% 77.3% 78.6% 75.4% 76.2% 0.40 0.53

How important is this for you? (blood glucose medications)

Not at all 0.5% 1.0% 0.9% 1.8% 0

Somewhat 3.5% 4.1% 2.7% 7.3% 3.6%

Acc

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Considerable 10.8% 12.7% 12.9% 10.1% 15.5%

Very 85.2% 82.3% 83.6% 80.7% 81% 0.7 0.20

How much of a burden is this for you? (blood glucose medications)

Not at all 67.2% 66.1% 67% 68.2% 56% Somewhat 23.4% 25.4% 26.2% 23.6% 34.5% Considerably 5.9% 5.8% 6.3% 4.5% 6.0% A great burden 3.5% 2.7% 3.5% 3.6% 3.6% 0.39 0.43

*Mann–Whitney U-test and Kruskal–Wallis test as appropriate.

†Burden tending to be less with greater BMI.

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