Central fat accretion and insulin sensitivity: differential relationships in parous and nulliparous women
Childbearing is associated with a disproportionate accumulation of visceral fat and an increased risk of metabolic disease. However, it is unknown whether the visceral fat accretion associated with pregnancy modifies a woman's risk for metabolic disease. The purpose of this study was to test whether the association between abdominal fat and insulin sensitivity differs by parity status in healthy overweight women.SUBJECTS/METHODS:
Intra-abdominal adipose tissue (IAAT) via CT, body composition by DXA, insulin sensitivity via intravenous glucose tolerance test and minimal model (SI), HOMA-IR, and cardiorespiratory fitness (VO2max) were assessed in 212 non-diabetic, premenopausal, overweight non-Hispanic white and African-American women.RESULTS:
Nulliparous women (n = 98) were younger, had less IAAT and higher VO2max, but similar SI, HOMA-IR and leg fat, compared to parous (n = 114). In nulliparous women, IAAT was negatively associated with SI, controlling for age, race and body fat mass (r = -0.40, P < 0.001), but this relationship was attenuated in parous women (r = -0.15, P = 0.16). In multiple linear regression analysis, leg fat and IAAT were significant predictors of SI in nulliparous, but not parous women.CONCLUSIONS:
Results suggest that greater IAAT in parous women does not lead to greater insulin resistance; rather, transient insulin resistance during pregnancy may encourage intra-abdominal fat accumulation that is metabolically benign. This underscores the need to consider parity when assessing cardiometabolic risk.