Ethnic variation in the contribution of Cardiorespiratory fitness and muscular

strength to diabetes: crossectional study of 68,116 UK Biobank participants

Uduakobong Ntuk,

Institute of Health and Wellbeing ,University of Glasgow

International Conference on Epidemiology & Public Health

Valencia Spain, 2015

OutlineBackgroundStudy AimsMethodsResultDiscussionStrengths and LimitationsConclusion

Background Type 2 diabetes is a major public health problem

Diabetes prevalence◦ Black (2x White European)

◦ South Asian (4x White European)

Background (cont’d)• Low cardiorespiratory fitness • involved in the progression from normal glucose metabolism to

type 2 diabetes (T2D);

• predictors of cardiovascular events and premature mortality in T2D individuals.

 • Muscular strength is a predictor of all-cause mortality,

as well as disability.

No epidemiological studies on ethnic variation and diabetes prevalence

Rantanen T, et al; Sayer AA, et al; Ghouri N, et al; Wander PL, et al

Study Aims To determine the associations of (a) cardiorespiratory

fitness (b) muscular strength on diabetes risk in White European, Black and South Asian.

To determine the extent to which ethnic differences in fitness and muscle strength might account for observed differences in diabetes prevalence

Whether the strength of these relationships similar across ethnic groups

MethodsData Source

UK Biobank◦ Large sample size data >500,000◦ Aged between 40 and 70 years◦ Representative of the UK population in terms of age-band, sex and

ethnic structure◦ Self-identified as White, South Asian or black background living in the

UK

Data Analysis◦ Multivariate logistic regression model◦ Adjusting for :

Age, Sex ,Deprivation quintile , Smoking , Alcohol consumption, BMI and Percentage body fat

Results

Table 1.Characteristics of study participants by ethnic group and sex

Men Women

WhiteN=28,402

Black N=904

South Asian N=1,066

White N=35,367

Black N=1,293

South Asian N=1,086

Age(years) 59 (51-64) 51 (45-59) 54 (45-61) 58 (51-63) 51 (46-58) 53 (46-60)

BMI (kg/m2) 27.2 (25.0-29.9)

28.2 (25.9-30.9)

26.5 (24.4-29.0)

25.9 (23.3-29.4)

29.5 (26.0-33.6)

26.3 (23.6-29.3

Hand grip strength (kg/kg body weight)

0.45 (0.28-0.53)

0.47 (0.37-0.55)

0.43 (0.35-0.50)

0.33 (0.26-0.39)

0.32 (0.25-0.38)

0.29 (0.23-0.36)

CRF (METS)10.02

(8.14-11.92)8.65

(6.85-10.27)9.20

(7.65-10.73)7.65

(6.09-9.31)6.49

(4.75-7.98)6.82

(5.31-8.21)

N (%) N (%) N (%) N (%) N (%) N (%)

Diabetes1,604 (5.64) 134 (14.77) 189 (17.68) 1,122 (3.17) 108 (8.34) 126 (11.60)

High strength

Moderate strength

Low strength

0

1

2

3

4

5

6

7

8

High fitness

Low fitness

1.88

3.654.78

2.493.76

5.022.70

3.90

5.86

Dia

bete

s o

dd

s r

ati

o

Black men

High

stre

ngth

Mod

erat

e st

reng

th

Low s

treng

th

0

2

4

6

8

High fitness

Low fitness1.00 1.06 1.64

1.00 1.24 1.76

1.32 1.94 2.41

Dia

bete

s o

dd

s r

ati

o

White men

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

0

1

2

3

4

5

6

7

8

High fitness

Low fitness

3.023.94 4.543.43 4.04

6.29

3.49

6.51 6.72

Dia

bete

s o

dd

s r

ati

o

South Asian men

Impact of fitness & strength on risk of diabetes (Men)

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

0

2

4

6

8

High fitness

Low fitness

1.14 2.11 2.621.27

3.312.96

3.52

5.88

4.05

Dia

bete

s o

dd

s r

ati

o

Black women

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

0

2

4

6

8

High fitness

Low fitness1.00 1.03 1.33

1.09 1.04 1.68

1.36 1.31 2.10

Dia

bete

s o

dd

s r

ati

o White women

High strength

Moderate strength

Low strength

0

1

2

3

4

5

6

7

8

High fitness

Moderate fitness

Low fitness

2.533.73

5.373.54

4.59

6.223.90

5.286.45

Dia

bete

s o

dd

s r

ati

o

South Asian women

Impact of fitness & strength on risk of diabetes (Women)

Breakdown of participantsby fitness & strength (men)

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

05

10152025303540

High fitness

Low fitness3.8 10.8

15.73.5 8.1

17.42.1

9.6

29.1

Pro

port

ion

of

pop

ula

tion

in

cate

gory

(%

)

Black men

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

0

10

20

30

40

High fitness

Low fitness

12.49.4

6.1

12.3 11.99.9

10.1 12.1 15.7

Pro

port

ion

of

pop

ula

tion

in

cate

gory

(%

)

White men

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

0

5

10

15

20

25

30

35

40

High fitness

Low fitness3.0 5.2

4.5

7.5 10.7 13.76.1

15.0

34.3

Pro

port

ion

of

pop

ula

tion

in

cate

gory

(%

)

South Asian women

Breakdown of participantsby fitness & strength (women)

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

0

5

10

15

20

25

30

35

40

High fitness

Low fitness4.4 6.2 7.1

4.911.1 14.06.3

15.8

30.2

Pro

port

ion

of

pop

ula

tion

in

cate

gory

(%

)

South Asian men

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

0

5

10

15

20

25

30

35

40

High fitness

Low fitness3.9

2.7 3.1

7.3 8.98.1

10.1

19.9

36.0

Pro

port

ion

of

pop

ula

tion

in

cate

gory

(%

)

Black women

High

stre

ngth

Mod

erat

e st

reng

th

Low stren

gth

05

10152025303540

High fitness

Low fitness

14.212.2

8.4

9.5 12.4 11.85.9 9.7

15.9

Pro

port

ion

of

pop

ula

tion

in

cate

gory

(%

)

White women

Table 2. Attributable risk and attributable fraction of low-to-moderate cardiorespiratory fitness and low-to-moderate muscular strength for diabetes in

White, Black and South Asian men and women

Men Women

White Black South Asian White Black South Asian

Attributable risk (diabetes cases per 100 people)

1.4 (0.5-2.3) 4.1 (3.5-10.9) 8.2 (2.3-18.6) 1.0 (0.5-1.5) 4.3 (2.2-7.8) 5.0 (2.8-12.5)

Attributable fraction for diabetes risk (%)

24.5 (6.3-39.1)

28.1 (22.5-60.4)

45.7 (18.8-81.2)

27.3 (5.1-44.3)42.6 (20.1-

79.9)47.2 (20.8-

86.6)

Discussion Findings suggest a graded association between weaker

muscular strength, low cardiorespiratory fitness and diabetes risk, particularly in South Asian and Black ethnic groups.◦ remained significant after adjustment for adiposity (BMI

and %body fat).

Need to include strength-training exercises, as well as aerobic physical activity, in future lifestyle interventions trials for diabetes prevention.

Need to target black and south Asian adults for interventions to increase strength and fitness.

Result (contd)

Strengths and Limitations Strength of study:– Primary predictors objectively measured – Large sample size– Ethnic diversity

Limitations:– Cross sectional study– Can not determine causal association– Selection bias?

Conclusion Independent associations between fitness and muscular

strength on diabetes risk in white European, south Asian and black adults

Low-to-moderate fitness and strength could importantly contribute to a disproportionately large proportion of diabetes cases in the south Asian and black groups

A clear case for future randomised controlled trials of interventions to improve both strength and fitness in non-white populations

Translating research into practice ……

The rest of the team ….. Jason M.R. Gill, Daniel F. Mackay, Naveed Sattar, Jill P. Pell

Thank you