LEP and obesity due to melanocortin 4 receptor deficiency: Given that higher leptin levels, as a by-product of increased fat mass, were associated with better survival in this dialysis cohort, it is possible that leptin’s favorable effects on nutritional status may overcome the ill effects of leptin-associated inflammation with respect to survival (i.e., higher leptin levels are a marker of obesity, which may paradoxically protect against the downstream effects of inflammation such as cardiovascular disease in dialysis patients) [42].