RELATIONSHIPS BETWEEN THYROID-HORMONE AND ANTIDEPRESSANT RESPONSES TOTOTAL SLEEP-DEPRIVATION IN MOOD DISORDER PATIENTS

Background: Acute transient antidepressant effects of sleep deprivatio n are consistently observed in 50% of depressed patients, but the mech anisms of these, at times, dramatic improvements in mood have not been adequately elucidated. Some, but not all, studies suggest a relations hip to increased thyroid-stimulating hormone (TSH) secretion. Methods: TSH and other thyroid indices were measured at 8:00 AM after a baseli ne night's sleep and at 8:00 AM following a night of total sleep depri vation (S.D.) in 34 medication-free, affective disorder patients asses sed with Hamilton, Beck, and Bunney-Hamburg depression ratings as well as two hourly self-ratings on a visual analog scale. Results: Compare d with baseline, S.D. induced highly significant increases in TSH, lev othyroxine, free levothyroxine, and triiodothyronine. The 12 S.D. resp onders tended to have greater TSH increases than the 15 nonresponders (p < .10). The change in Beck depression ratings significantly correla ted with the change in TSH (r = -.40, p = .0496, n = 24). Conclusions: These data are consistent with several other reports of a significant relationship between degree of antidepressant response to S.D. and in creases in TSH measured at 8:00 AM near their usual nadir. Acute remov al of the sleep-related break on the hypothalamic-pituitary-thyroid ax is remains a promising candidate for the mechanism of sleep deprivatio n-induced improvement in mood in depressed patients. (C) 1998 Society of Biological Psychiatry.