Counterintuitive relationship between visceral fat and all-cause mortality in an elderly Asian population.

Abstract

Abdominal obesity is considered to be a risk factor for mortality. However, recent studies indicate that overweight may be negatively associated with mortality ("obesity paradox"). The relationships between mortality and various obesity markers in an elderly Asian cohort were evaluated. Subjects of the Korean Longitudinal Study on Health and Aging (KLoSHA) (n = 1000, age ≥65 years) were included. The visceral fat area (VFA) and subcutaneous fat area (SFA) were measured using computed tomography. A total of 222 deaths occurred during the 6-year follow-up (median = 5.2 [range 0.1-6.3] years). Body mass index (BMI), VFA, SFA, and total fat mass were negatively associated with all-cause mortality in the univariable analyses (hazard ratio [HR] 0.67 per 1 SD [95% CI 0.57-0.77], 0.66 [0.55-0.79], 0.73 [0.61-0.86], and 0.74 [0.63-0.87], respectively). BMI and VFA were significantly associated with all-cause mortality in the multivariable analyses (HR 0.85 per 1 SD [95% CI 0.73-0.99] and 0.64 [0.47-0.87], respectively). When stratified by quartiles, the HR associated with VFA was the lowest in the third quartile. In this observational study with a short follow-up of elderly Asian people, higher amounts of visceral fat, a marker for central obesity, were associated with decreased all-cause mortality.