Chronotype influences response to antidepressant chronotherapeutics in bipolar patients.

Patient diurnal mood fluctuation, sleep characteristics and factors affecting sleep homeostasis predict antidepressant response to the combination of total sleep deprivation and light therapy (TSD + LT). In order to study if chronotype could influence response to TSD+LT, we considered 194 bipolar depressed patients. Severity of depression was rated with Hamilton Depression Rating Scale; perceived mood levels were assessed by a self-administered 10-cm visual analogue scale and chronotype was assessed using the Mornigness-Eveningness Questionnaire. More than 60% of patients resulted responders to treatment with chronotype influencing the antidepressant response with evening type subjects showing higher response rates.