Electroconvulsive therapy increases circadian amplitude and lowers core body temperature in depressed subjects

BACKGROUND: Reduced amplitude of the circadian temperature rhythm and elevated nocturnal body temperature normalize after successful pharmacotherapy of major depression. METHODS: Core body temperature was continually monitored in three groups: a) 6 depressed patients before an electroconvulsive therapy (ECT) course and b) after an ECT course; and c) 6 healthy, sex-matched controls of similar age. RESULTS: The 24-hour profile of temperature was significantly different in patients pre-ECT than in patients post-ECT or in controls. Post-ECT subjects and controls manifested 24-hour profiles similar to one another. Circadian temperature rhythm amplitude increased after ECT. The mean asleep and mean 24-hour temperatures were significantly higher in patients pre-ECT than post-ECT and controls. CONCLUSIONS: We find that ECT restores a disrupted circadian temperature rhythm in depressed patients.