Body Weight and Mortality: New Population Based Evidences Body Weight and Mortality: New Population...

Body Weight and Mortality:Body Weight and Mortality: New Population Based New Population Based EvidencesEvidences

Dongfeng Gu, MDDongfeng Gu, MD

Fu Wai Hospital and CVD Institute Chinese Academy of Medical Sciences, Beijing, PR China,

National Center of CVD, China

22

BackgroundBackground Prevalence of overweight and obesity has increased Prevalence of overweight and obesity has increased

in China and in other economically developing in China and in other economically developing countries.countries.

The prevalence of overweight and obesity is The prevalence of overweight and obesity is essential for strategies of effective prevention and essential for strategies of effective prevention and control for obesity, diabetes, hypertension and CVD.control for obesity, diabetes, hypertension and CVD.

The effect of underweight and obesity on mortality The effect of underweight and obesity on mortality has not been well characterized in Asian has not been well characterized in Asian populationspopulations..

33

BackgroundBackground Obesity is a strong risk factor for diabetes, coronary heat Obesity is a strong risk factor for diabetes, coronary heat

disease, stroke, and some types of cancer. However, the disease, stroke, and some types of cancer. However, the association between body weight and all-cause mortality association between body weight and all-cause mortality is more controversial: a direct association or a J-shaped or is more controversial: a direct association or a J-shaped or U-shaped relationship have been reported in recent U-shaped relationship have been reported in recent studiesstudies . .

Most of these studies have been conducted in Western Most of these studies have been conducted in Western populations with only a small proportion of the study populations with only a small proportion of the study participants have had a low body-mass indexparticipants have had a low body-mass index..

44

BackgroundBackground Several epidemiological studies have suggested that Several epidemiological studies have suggested that

Asian populations have higher amounts of body fat and Asian populations have higher amounts of body fat and prevalence of cardiovascular disease risk factors at lower prevalence of cardiovascular disease risk factors at lower levels of body-mass index compared to their counterparts levels of body-mass index compared to their counterparts in Western populationsin Western populations..

WHO, IASO, and IOTF have suggested lower BMI WHO, IASO, and IOTF have suggested lower BMI cutoffs for overweight (23.0-24.9 kg/mcutoffs for overweight (23.0-24.9 kg/m22) and for obesity ) and for obesity (≥25.0 kg/m(≥25.0 kg/m22) in Asian populations, labeling these ) in Asian populations, labeling these recommendations as provisional and calling for their recommendations as provisional and calling for their validation in clinical and epidemiologic studies.validation in clinical and epidemiologic studies.

55

CHEFS - ObjectivesCHEFS - Objectives The Chinese National Hypertension The Chinese National Hypertension

Survey Epidemiologic Follow-up Study Survey Epidemiologic Follow-up Study (CHEFS).(CHEFS).

Prospective cohort study in a nationally Prospective cohort study in a nationally representative sample of 169,871 representative sample of 169,871 Chinese men and women aged 40 years Chinese men and women aged 40 years and older. and older.

To examine the relation between body To examine the relation between body weightweight and risk of CVD, cancer or other and risk of CVD, cancer or other causes of death in the Chinese Adult causes of death in the Chinese Adult population. population.

66

Methods Methods –– Definitions Definitions

Multivariate-adjusted relative risk was calculated Multivariate-adjusted relative risk was calculated using study participants with a body-mass index of using study participants with a body-mass index of 24.0-24.9 kg/m24.0-24.9 kg/m22 as the reference because this group as the reference because this group had the lowest mortality.had the lowest mortality.

Cox proportional hazards models were used to adjust Cox proportional hazards models were used to adjust for baseline age, gender, cigarette smoking, alcohol for baseline age, gender, cigarette smoking, alcohol consumption, physical activity, education, geographic consumption, physical activity, education, geographic region (north vs. south) and urbanization (urban vs. region (north vs. south) and urbanization (urban vs. rural)rural)..

77

ResultsResults

During an average follow-up of 8.3 years During an average follow-up of 8.3 years (1,113,162 person-years), 17,687 deaths were (1,113,162 person-years), 17,687 deaths were documented. There was a statistically documented. There was a statistically significant U-shaped association between significant U-shaped association between body-mass and age-standardized mortality body-mass and age-standardized mortality from all-causes (p<0.0001) with the lowest from all-causes (p<0.0001) with the lowest mortality among study participants with a mortality among study participants with a body-mass index (kg/mbody-mass index (kg/m22) of 24.0-24.9 in men ) of 24.0-24.9 in men and 25.0-26.9 in women.and 25.0-26.9 in women.

1010

0.0

0.5

1.0

1.5

2.0

2.5

Body Mass Index, kg/m2

Rel

ativ

e R

isk

Age <65 Years (7621 deaths)

1111

0.0

0.5

1.0

1.5

2.0

2.5


Rel

ativ

e R

isk

Age ≥65 Years (10066 deaths)

1212

0.0

0.5

1.0

1.5

2.0

2.5

<18.5

18.5

-19.

9

20.0

-20.

9

21.0

-21.

9

22.0

-22.

9

23.0

-23.

9

24.0

-24.

9

25.0

-26.

9

27.0

-29.

9

≥30

.0


Rel

ativ

e R

isk

Never-Smokers (9894 deaths)

1313

0.0

0.5

1.0

1.5

2.0

2.5

<18.5

18.5

-19.

9

20.0

-20.

9

21.0

-21.

9

22.0

-22.

9

23.0

-23.

9

24.0

-24.

9

25.0

-26.

9

27.0

-29.

9

≥30

.0


Rel

ativ

e R

isk

Current or Former Smokers (7775 deaths)

1414

0.0

0.5

1.0

1.5

2.0

2.5


Rel

ativ

e R

isk

No History of Disease at Baseline (15925 deaths)

1515

0.0

0.5

1.0

1.5

2.0

2.5


Rel

ativ

e R

isk

Not Died in First 3-Years of Follow-up (12473 deaths)

1616

0.0

0.5

1.0

1.5

2.0

2.5

<18.5

18.5

-19.

9

20.0

-20.

9

21.0

-21.

9

22.0

-22.

9

23.0

-23.

9

24.0

-24.

9

25.0

-26.

9

27.0

-29.

9

≥30

.0


Rel

ativ

e R

isk

No Heavy Alcohol Drinkers (16370 deaths)

1717

0.0

0.5

1.0

1.5

2.0

2.5

<18.5

18.5

-19.

9

20.0

-20.

9

21.0

-21.

9

22.0

-22.

9

23.0

-23.

9

24.0

-24.

9

25.0

-26.

9

27.0

-29.

9

≥30

.0


Rel

ativ

e R

isk

Cardiovascular Mortality (8079 deaths)

1818

0.0

0.5

1.0

1.5

2.0

2.5

<18.5

18.5

-19.

9

20.0

-20.

9

21.0

-21.

9

22.0

-22.

9

23.0

-23.

9

24.0

-24.

9

25.0

-26.

9

27.0

-29.

9

≥30

.0


Rel

ativ

e R

isk

Cancer Mortality (3929 deaths)

1919

0.0

0.5

1.0

1.5

2.0

2.5

<18.5

18.5

-19.

9

20.0

-20.

9

21.0

-21.

9

22.0

-22.

9

23.0

-23.

9

24.0

-24.

9

25.0

-26.

9

27.0

-29.

9

≥30

.0


Rel

ativ

e R

isk

Other Cause Mortality (5679 deaths)

2121

Prospective Studies Collaboration in Prospective Studies Collaboration in China China

Cohorts profileCohorts profile MenMen WomenWomen

No. of cohortsNo. of cohorts 2424 1919

No. of participantsNo. of participants 5491454914 3828038280 F-U,YearF-U,Year 7.17.1 6.36.3

Total person-yearsTotal person-years 387256387256 241250241250

No. of deathNo. of death 30443044 15761576

Age (years)Age (years) RangeRange 20-9420-94 20-9820-98

2222

Relative risk of all-cause mortality and BMI with 628364 person-years FUH

R&

95%

CIH

R&

95%

CI

40-59y 60y+

BMI BMI BMI

20-39y

1

2

3

17 19 21 23 25 27 29 3117 19 21 23 25 27 29 31

0

1

2

3

17 19 21 23 25 27 29 31

Adjusted for age, cohort, smoking, alcohol drinking and SBP, follow-up<1y excluded

Female

Male

2323

Accumulated mortality (1/100 participants in 7 yrs) and BMI in men, by age group

All-cause

0

5

10

15

20

25

30

CVD

0

2

4

6

8

10

12

14

cancer

0

1

2

3

4

5

6

7

Other causes

0

2

4

6

8

10

20-39y 40-59y 60y+20-39y 40-59y 60y+

Only those FU>1y included

12=BMI<18 18=<BMI<20 24=<BMI<2822=<BMI<2420=<BMI<22 BMI>=28

Mor

talit

y

2424BMI and CVD in the Asia-Pacific Region: 33 cohorts involving 310 000 participants

Asia Pacific Cohort Studies Collaboration Int J Epidem, 2004

2525

0.0

0.5

1.0

1.5

2.0

2.5

<18.5

18.5

-19.

9

20.0

-20.

9

21.0

-21.

9

22.0

-22.

9

23.0

-23.

9

24.0

-24.

9

25.0

-26.

9

27.0

-29.

9

≥30

.0


Rel

ativ

e R

isk

Other Cause Mortality (5679 deaths)

2626

Age-Standardized Prevalence of Age-Standardized Prevalence of Overweight and Obesity in the Adult Overweight and Obesity in the Adult Population Aged 35-74 Years by Geographic Population Aged 35-74 Years by Geographic Region and Urbanization Region and Urbanization in China, 2000-2001in China, 2000-2001

43.5

6.7

18.6

1.8

39.1

5.3

26.6

3.5

0

5

10

15

20

25

30

35

40

45

50

Pre

va

len

ce

of

Ov

erw

eig

ht,

%

North

South

Urban

Rural

≥ 25.0

BMI, kg/m2

≥30.0

2727

Age-Standardized Prevalence of BMI Age-Standardized Prevalence of BMI Cut-points Among Men and Women Cut-points Among Men and Women Aged 35-74 Years in China, 2000-Aged 35-74 Years in China, 2000-20012001

46.9

36.4

26.9

8.2

2.8

51.7

40.2

31.0

11.6

5.0

0

10

20

30

40

50

60

Pre

va

len

ce

of

Ov

erw

eig

ht,

% Men

Women

23.0

BMI, kg/m2

24.0 25.0 28.0 30.0

2828

Estimated Number of Overweight and Obese Adults Aged 35-74 Years in China,

2000-2001

11

27

72

93

120

7

20

66

89

114

18

47

137

182

234

0 50 100 150 200 250

Est

imat

ed N

um

ber

in

Mil

lio

ns

TotalMenWomen ≥ 30 kg/m2

≥ 23 kg/m2

≥ 25 kg/m2

≥ 24 kg/m2

≥ 28 kg/m2

2929

ResultsResults

During an average follow-up of 8.3 years During an average follow-up of 8.3 years (1,113,162 person-years), 17,687 deaths were (1,113,162 person-years), 17,687 deaths were documented. There was a statistically documented. There was a statistically significant U-shaped association between significant U-shaped association between body-mass and age-standardized mortality body-mass and age-standardized mortality from all-causes (p<0.0001) with the lowest from all-causes (p<0.0001) with the lowest mortality among study participants with a mortality among study participants with a body-mass index (kg/mbody-mass index (kg/m22) of 24.0-24.9 in men ) of 24.0-24.9 in men and 25.0-26.9 in women.and 25.0-26.9 in women.

3030

ConclusionConclusion

The lowest rates of death from all-causes were at a body-mass index between 24.0-24.9 kg/m2 in Chinese men and 25.0-26.9 kg/m2 in Chinese women.

BMI <18.5 or 18.5-22.9 kg/m2) had a significantly increased all-cause mortality.

BMI > 27.0 in men and >30.0 in women was associated with an increased all-cause mortality.

3131


It certainly indicate that BMI <18 at the highest risk of any kind of death. The risk of cancer, CVD and other causes of death decreased with BMI from 18-27.9. The risk only increased after BMI>=28, but is still lower than BMI at 18-22, for CVD, cancer and other causes of death.

Western populations have identified the lowest all-cause mortality among persons with a body-mass index between 23 and 27.

3232


The U-shaped association was observed between The U-shaped association was observed between body weight and mortality from cardiovascular body weight and mortality from cardiovascular disease, cancer, and other causes.disease, cancer, and other causes.

The current studies indicates that both underweight The current studies indicates that both underweight and obesity were associated with increased mortality and obesity were associated with increased mortality in the Chinese adult population. Furthermore, our in the Chinese adult population. Furthermore, our findings support the use of a single common findings support the use of a single common recommendation for defining overweight and recommendation for defining overweight and obesity among all race and ethnicity groups.obesity among all race and ethnicity groups.

3333

AcknowledgementAcknowledgement Participating InstitutesParticipating Institutes

– Cardiovascular Institute of Chinese Academy Cardiovascular Institute of Chinese Academy of Medical Sciences, Beijing, Chinaof Medical Sciences, Beijing, China

– 10 Provinces including10 Provinces including– Fujian, Guangxi, Jiangsu, Hubei, Fujian, Guangxi, Jiangsu, Hubei,

Sichuan,Sichuan,– Shandong, Beijing, Jilin, Shanxi, Qinghai Shandong, Beijing, Jilin, Shanxi, Qinghai – Tulane University School of Public Health and Tulane University School of Public Health and

Tropical Medicine, New Orleans, LA, USATropical Medicine, New Orleans, LA, USA– Institute for International Health, University Institute for International Health, University

of Sydney, Sydney, Australiaof Sydney, Sydney, Australia– National Health Foundation, Mahidol National Health Foundation, Mahidol

University, Bangkok, ThailandUniversity, Bangkok, Thailand

Body Weight and Mortality: New Population Based Evidences Body Weight and Mortality: New Population...

Documents

Transcript of Body Weight and Mortality: New Population Based Evidences Body Weight and Mortality: New Population...