Midlife body mass index and hospitalization and mortality in older age.
BACKGROUND
Abundant evidence links overweight and obesity with impaired health. However, controversies persist as to whether overweight and obesity have additional impact on cardiovascular outcomes independent of their strong associations with established coronary risk factors, eg, high blood pressure and high cholesterol level.


OBJECTIVE
To assess the relation of midlife body mass index with morbidity and mortality outcomes in older age among individuals without and with other major risk factors at baseline.


METHODS
Chicago Heart Association Detection Project in Industry study, a prospective study with baseline (1967-1973) cardiovascular risk classified as low risk (blood pressure < or =120/< or =80 mm Hg, serum total cholesterol level <200 mg/dL [5.2 mmol/L], and not currently smoking); moderate risk (nonsmoking and systolic blood pressure 121-139 mm Hg, diastolic blood pressure 81-89 mm Hg, and/or total cholesterol level 200-239 mg/dL [5.2-6.2 mmol/L]); or having any 1, any 2, or all 3 of the following risk factors: blood pressure > or =140/90 mm Hg, total cholesterol level > or =240 mg/dL (6.2 mmol/L), and current cigarette smoking. Body mass index was classified as normal weight (18.5-24.9), overweight (25.0-29.9), or obese (> or =30). Mean follow-up was 32 years.


METHODS
Participants were 17,643 men and women aged 31 through 64 years, recruited from Chicago-area companies or organizations and free of coronary heart disease (CHD), diabetes, or major electrocardiographic abnormalities at baseline.


METHODS
Hospitalization and mortality from CHD, cardiovascular disease, or diabetes, beginning at age 65 years.


RESULTS
In multivariable analyses that included adjustment for systolic blood pressure and total cholesterol level, the odds ratio (95% confidence interval) for CHD death for obese participants compared with those of normal weight in the same risk category was 1.43 (0.33-6.25) for low risk and 2.07 (1.29-3.31) for moderate risk; for CHD hospitalization, the corresponding results were 4.25 (1.57-11.5) for low risk and 2.04 (1.29-3.24) for moderate risk. Results were similar for other risk groups and for cardiovascular disease, but stronger for diabetes (eg, low risk: 11.0 [2.21-54.5] for mortality and 7.84 [3.95-15.6] for hospitalization).


CONCLUSIONS
For individuals with no cardiovascular risk factors as well as for those with 1 or more risk factors, those who are obese in middle age have a higher risk of hospitalization and mortality from CHD, cardiovascular disease, and diabetes in older age than those who are normal weight.
Yan
Lijing L
LL
Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Ill 60611, USA. lijing@northwestern.edu
Daviglus
Martha L
ML
Liu
Kiang
K
Stamler
Jeremiah
J
Wang
Renwei
R
Pirzada
Amber
A
Garside
Daniel B
DB
Dyer
Alan R
AR
Van Horn
Linda
L
Liao
Youlian
Y
Fries
James F
JF
Greenland
Philip
P
D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology; D002423:Cause of Death; D002641:Chicago / Q000453:epidemiology; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D015999:Multivariate Analysis; D009765:Obesity; D050177:Overweight; D011446:Prospective Studies; D012307:Risk Factors