Sleep apnea and hypothyroidism presenting as depression in two patients

Two patients are described who presented with depression and were later found to have both obstructive sleep apnea and hypothyroidism. Both patients had normal thyroxine (T4) levels but elevated thyroid-stimulating hormone (TSH) levels. Thyroid replacement led to resolution of both apnea and depression. The possibility of hypothyroidism as a cause of sleep apnea and depression is discussed.