INS and obesity due to melanocortin 4 receptor deficiency: Wang et al. found that obese rats (Zucker fatty rats) exhibit insulin resistance, increased frequency of urination and decreased leak point pressure (LPP) compared to controls (Zucker lean rats),26 in addition to increased intramuscular lipid deposition in urethral transverse muscle fibres in obese rats, suggesting that obesity may contribute to urinary incontinence by affecting urethral sphincter function,27 thus providing insight into whether obesity and muscle loss or weakness may increase the risk of developing urinary incontinence.