Association of body mass index with life expectancy with and without cardiovascular disease

We estimated the average numbers of years lived with and without cardiovascular disease (CVD) in normal weight, overweight, and obese individuals, aged ≥30 years.

A total of 7529 participants were recruited. The multi-state Markov model was used to obtain hazard ratios (HRs) for three transitions (CVD free to nonfatal CVD, CVD free to all-cause death, and nonfatal CVD to all-cause death) stratified by body mass index (BMI) categories at baseline and adjusted for confounders including sex, age, smoking, family history of premature CVD, education and physical activity. Life expectancies (LEs) were also estimated for each transition stratifying by BMI categories and sex.

We found 986 incident cases of nonfatal CVD and 669 overall deaths (236 CVD deaths) after more than 18 years of follow-up. Overweight and obesity were associated with an increased risk of nonfatal CVD (HR, 1.42 (95% confidence interval (CI) 1.21-1.66) and (1.64, 1.37-1.96), respectively), compared with normal weight individuals. Overweight and obesity were also associated with lower risk of mortality without CVD (0.39, 0.20-0.77) and (0.35, 0.14-0.85), respectively. Among those with CVD, overweight compared with normal weight was associated with a lower risk of mortality (0.72, 0.56-0.94). Total LEs for both men and women with overweight and obesity were not significantly different from their normal weight counterparts. Compared with normal weight individuals, men and women with obesity lived 4.1 (CI: -6.3, -1.3) and 4.3 (-6.4, -2.0) fewer years free of CVD; however, they lived 3.9 (2.1, 6.0) and 3.7 (2.1, 5.6) longer years with CVD than their normal weight counterparts, respectively.

We demonstrated that although total LE was not influenced by higher BMI; individuals with overweight and obesity could expect longer longevity after diagnosis of nonfatal CVD. These extra years of life impose financial burden on both patients and the health care system.