Body mass index and mortality among US male physicians☆
Received 24 June 2002; accepted 28 October 2003. published online 19 August 2004.
Abstract
Purpose
To assess the relationship between body mass index and mortality in a population homogeneous in educational attainment and socioeconomic status.
Methods
We analyzed the association between body mass index (BMI) and both all-cause and cause-specific mortality among 85,078 men aged 40 to 84 years from the Physicians' Health Study enrollment cohort.
Results
During 5 years of follow-up, we documented 2856 deaths (including 1212 due to cardiovascular diseases and 891 due to cancer). In age-adjusted analyses, we observed a U-shaped relation between BMI and all-cause mortality; among men who never smoked a linear relation was observed with no increase in mortality among leaner men (P for trend, <0.001). Among never smokers, in multivariate analyses adjusted for age, alcohol intake, and physical activity, the relative risks of all-cause mortality increased in a stepwise fashion with increasing BMI. Excluding the first 2 years of follow-up further strengthened the association (multivariate relative risks, from BMI<20 to ⩾30 kg/m2, were 0.93, 1.00, 1.00, 1.16, 1.45, and 1.71 [P for trend, <0.001]). In all age strata (40–54, 55–69, and 70–84 years), never smokers with BMIs of 30 or greater had approximately a 70% increased risk of death compared with the referent group (BMI 22.5–24.9). Higher levels of BMI were also strongly related to increased risk of cardiovascular mortality, regardless of physical activity level (P for trend, <0.01).
Conclusions
All-cause and cardiovascular mortality was directly related to BMI among middle-aged and elderly men. Advancing age did not attenuate the increased risk of death associated with obesity. Lean men (BMI<20) did not have excess mortality, regardless of age.
From the Division of Preventive Medicine (U.A.A., P.A.L., J.M.G., I.-M.L., A.S., J.E.B., J.E.M.) and Channing Laboratory (W.C.W., J.E.M.), Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Departments of Epidemiology (I.-M.L., J.E.B., W.C.W., J.E.M.) and Nutrition (W.C.W.), Harvard School of Public Health, Boston, MA; Massachusetts Veterans Epidemiology Research and Information Center, Veterans Affairs Medical Center, Brockton/West Roxbury, MA (J.M.G.); School of Public Health, University of North Texas Health Science Center, Fort Worth, TX (U.A.A.); and the Department of Internal Medicine, School of Medicine and Division of General Internal Medicine, Hospital Universitario, University of Sao Paulo, Sao Paulo, Brazil (P.A.L.)
Address correspondence and reprint requests to: JoAnn E. Manson, M.D., Dr.P.H., Division of Preventive Medicine, Brigham and Women's Hospital, 900 Commonwealth Avenue East, Boston, MA 02215. Tel.: (617) 278-0871; Fax: (617) 731-3843.
☆ Supported by a grant (HL-42441) from the National Institutes of Health, Bethesda, MD, USA. Dr. Lotufo is the recipient of a fellowship (97-02424-8) from FAPESP (Fundação de Amparo a Pesquisa do Estado de São Paulo), São Paulo, Brazil.
ABSTRACT