Eight-year change in body mass index and subsequent risk of cardiovascular disease among healthy non-smoking men.

Abstract

To determine how change in BMI over 8 years is associated with risk of subsequent cardiovascular disease (CVD) among middle aged men. Prospective cohort study among 13,230 healthy men (aged 51.6+/-8.7 years) in the Physicians' Health Study. BMI was collected at baseline in 1982 and after 8 years, at which time follow-up began. Subsequent CVD events were collected and confirmed through March 31, 2005. Cox proportional hazards models evaluated BMI at 8 years and risk of CVD, 8-year change in BMI and risk of CVD, and whether change in BMI added prognostic information after the consideration of BMI at 8 years. 1308 major CVD events occurred over 13.5 years. A higher BMI at year 8 was associated with an increased risk of CVD. Compared to a stable BMI (+/-0.5 kg/m(2)), a 0.5-2.0 kg/m(2) increase had a multivariable-adjusted RR of 1.00 (0.86-1.16). A >/=2.0 kg/m(2) increase had a multivariable-adjusted RR of 1.39 (1.16-1.68), however further adjustment for BMI reduced the RR to 1.00 (0.81-1.23). A decrease in BMI had a multivariable RR of 1.23 (1.07-1.42) which was unaffected by adjustment for BMI at 8 years. A higher BMI and a rising BMI were both associated with an increased risk of CVD, however an increasing BMI did not add prognostic information once current BMI was considered. In contrast, a declining BMI was associated with an increased risk of CVD independent of current BMI.