PLASMA MELATONIN AND CORTISOL IN PATIENTS WITH OBSESSIVE-COMPULSIVE DISORDER - RELATIONSHIP WITH AXILLARY TEMPERATURE, PHYSICAL-ACTIVITY, AND CLINICAL SYMPTOMS

Background: Many studies have found biological abnormalities in obsess ive-compulsive disorder (OCD), although most of them have not been rep licated. The investigation of melatonin rhythm may thus proline an ind irect clue to neurotransmitter alterations, and allow a biological com parison with depression. Methods: The circadian variations of plasma m elatonin, plasma cortisol, axillary temperature, motor activity, and o bsessive-compulsive symptoms have been documented on a circadian basis in 8 patients with OCD compared to 8 paired healthy volunteers. Resul ts: The circadian pattern of axillary! temperature was slightly differ ent in OCD patients when compared to control subjects. No significant difference between the two groups could be observed for any other vari able studied. Conclusions: The discrepancies with previous studies are discussed on the basis of the methods used (patients and control subj ects samples, biological measurement procedures). An alteration of tem perature circadian rhythm hypothesis is suggested. (C) 1998 Society of Biological Psychiatry.