Comparison of regional body composition and its relation with cardiometabolic risk between BMI-matched young and old subjects

Objective: Difference in regional body composition between young and old people may be related with differential cardiometabolic risks. We investigated regional body composition in BMI-matched young and old subjects to compare its relation with cardiometabolic risk. Methods: We recruited 1:3 gender- and BMI-matched 86 young subjects (mean age 27.3 +/- 2.9 years) and 258 older subjects (75.6 +/- 8.2 years) from a community. Abdominal visceral (VAT) and subcutaneous adipose tissue (SAT) and muscle area at mid-thigh level were evaluated by computed tomography. Fat depots in the gynoid area and lower extremity were measured by dual energy X-ray absorptiometry. Adiponectin, retinol binding protein-4 (RBP-4), and C-reactive protein (CRP) concentrations, pulse wave velocity (PWV) and ankle-brachial index (ABI) were measured for cardiometabolic risk. Results: VAT was greater in older subjects while SAT was almost the same, resulting in twice higher VAT/SAT ratio in older men and women (1.03 +/- 0.37 and 0.57 +/- 0.18) than younger counterparts (0.55 +/- 0.24 and 0.23 +/- 0.23) (both P < 0.01). Fat mass in the gynoid area and lower extremity was smaller in older subjects than younger subjects. The VAT correlated with adiponectin level negatively and RBP-4 level positively while gynoid fat correlated with them in opposite direction. The CRP levels negatively correlated with mid-thigh muscle in older subjects. Older subjects had higher PWV and lower ABI compared to BMI-matched younger counterparts. Conclusion: In conclusion, older adults in this cohort had increased visceral fat and decreased gynoid and lower extremity fat, along with less muscle mass. These findings may help explain the worse cardiometabolic profiles in the elderly who have the same BMI as the young. Crown Copyright (c) 2012 Published by Elsevier Ireland Ltd. All rights reserved.