Decreased nocturnal synthesis of melatonin in patients with coronary artery disease.

In human beings, cardiovascular activity has a distinct circadian variation: Heart rate, blood pressure, and vascular tone decrease at night. Nocturnal cardiovascular blunting is at least partially linked to the autonomic activity and increased risk of cardiac and cerebral events. To assess whether decreased nocturnal melatonin synthesis and secretion in coronary artery disease (CAD), we investigated nocturnal secretion pattern of melatonin in patients with CAD and healthy subjects.