Higher central fat mass and lower peripheral lean mass are independent determinants of endothelial dysfunction in the elderly: the Hoorn study.

Objective: To investigate whether an adverse body composition is associated with endothelial dysfunction (ED) and the extent to which any such association could be explained by low-grade inflammation (LGI) and/or insulin resistance (HOMA2-IR).

Methods: We studied 475 individuals from the Hoorn Study [mean (range) age, 68.9 (60-87) years, 245 women). Body composition was assessed by whole body dual-energy absorptiometry. Endothelial dysfunction was measured functionally, by flow-mediated dilation (FMD) and by circulating biomarkers. Associations were examined with multiple linear regression models and mediation analyses according to the ab product of coefficients method.

Results: After adjustment for age, sex, glucose metabolism status, prior cardiovascular disease and lifestyle factors, total and central fat mass were positively associated with the ED score [β = 0.16 (95% CI 0.04-0.29) and β = 0.18 (0.05-0.31), respectively] and inversely, although not statistically significantly, with FMD. Peripheral fat mass was not associated with the ED score or FMD. There was a significant favourable association between peripheral lean mass and FMD [β = 0.13 (0.00-0.26)], but not with the ED score. The association between total and central fat mass and the ED score was, to a great extent, mediated by LGI and HOMA2-IR. In contrast, LGI or HOMA2-IR did not mediate the association between peripheral lean mass and FMD.

Conclusion: Higher levels of central, but not peripheral fat mass were adversely associated with ED, which was attributable to body composition-related LGI and insulin resistance. In contrast, peripheral lean mass was beneficially associated with ED, but this seemed to be unrelated to LGI or insulin resistance.