Total and regional adiposity measured by dual-energy X-ray absorptiometry and mortality in NHANES 1999-2006

Abstract

Objective: Associations of overall and regional body fat measured by dual-energy X-ray absorptiometry with total and cause-specific mortality in the National Health and Nutrition Examination Survey (NHANES) 1999-2006 were investigated.

Methods: This study included 9,471 participants (≥20 years) free of major chronic diseases at baseline. Death information was obtained from the National Death Index (mean follow-up duration: 8.8 years).

Results: A total of 682 participants died after 12 months since baseline, with 206 and 170 deaths attributed to cardiovascular diseases (CVD) and cancer, respectively. The second quartile of fat mass percentages (FM%) was used as the reference to account for potential nonlinearity. In the multivariate-adjusted model, participants in the highest quartile of total FM% had increased total mortality; hazard ratio (HR; 95% confidence interval, 95% CI) was 1.48 (1.07-2.04; P < 0.05). Higher total and trunk FM%, but not leg FM%, were significantly associated with an increased CVD mortality; HRs (95% CIs) in the highest quartiles of total, trunk, and leg FM% were 2.24 (1.17-4.31), 1.93 (1.02-3.66), and 1.50 (0.77-2.94), respectively.

Conclusions: Higher total body fat was associated with increased total mortality in U.S. adults. Higher total and trunk fat contents were also associated with increased CVD mortality, although fat accumulation in the lower body was not an independent predictor of mortality.