The role of insulin resistance in the relation of visceral, abdominal subcutaneous and total body fat to cardiovascular function

Background and aimsThe separate cardiovascular effects of type 2 diabetes and adiposity remain to be examined. This study aimed to investigate the role of insulin resistance in the relations of visceral (VAT), abdominal subcutaneous (aSAT) adipose tissue and total body fat (TBF) to cardiovascular remodeling.Methods and resultsIn this cross-sectional analysis of the population-based Netherlands Epidemiology of Obesity study, 914 middle-aged individuals (46% men) were included. Participants underwent magnetic resonance imaging. Standardized linear regression coefficients (95%CI) were calculated, adjusted for potential confounding factors. All fat depots and insulin resistance (HOMA-IR), separate from VAT and TBF, were associated with lower mitral early and late peak filling rate ratios (E/A): −0.04 (−0.09;0.01) per SD (54 cm2) VAT; −0.05 (−0.10;0.00) per SD (94 cm2) aSAT; −0.09 (−0.16;-0.02) per SD (8%) TBF; −0.11 (−0.17;-0.05) per 10-fold increase in HOMA-IR, whereas VAT and TBF were differently associated with left ventricular (LV) end-diastolic volume: −8.9 (−11.7;-6.1) mL per SD VAT; +5.4 (1.1;9.7) mL per SD TBF. After adding HOMA-IR to the model to evaluate the mediating role of insulin resistance, change in E/A was −0.02 (−0.07;0.04) per SD VAT; −0.03 (−0.08;0.02) per SD aSAT; −0.06 (−0.13;0.01) per SD TBF, and change in LV end-diastolic volume was −7.0 (−9.7;-4.3) mL per SD VAT. In women, adiposity but not HOMA-IR was related to higher aortic arch pulse wave velocity.ConclusionInsulin resistance was associated with reduced diastolic function, separately from VAT and TBF, and partly mediated the associations between adiposity depots and lower diastolic function.