LEP and obesity due to melanocortin 4 receptor deficiency: ° No associations between leptin levels and depressed mood or sleep disturbances (f, m). ° Associations between leptin levels and an interaction between depressed mood and sleep disturbances (f). ° Higher leptin levels related to depressed mood and sleep disturbances in normal weight people (f). ° For people with obesity and elevated leptin levels no associations between higher leptin levels and depressed mood and sleep disturbances (f).