However, whilst omental fat clearly has a role in mediating the link between depression and IR and leptin levels, within the present study regression analysis of waist circumference vs. HOMA IR and leptin showed that the associations were relatively modest (R2 = 0.188 and 0.368), suggesting that other pathways, such as depression-linked excitation of the HPA axis, may also play a significant role in inducing metabolic derangement. Here, LEP is linked to major depressive disorder.