Weak 24-h periodicity of body temperature and increased plasma vasopressin in melancholic depression.

Earlier work has shown that plasma vasopressin levels of depressed patients were higher than those of healthy controls. The aim of the present study was to determine whether plasma vasopressin levels were correlated to parameters of the circadian rhythm. 41 patients with major depression (aged 22-77 yrs)and 25 controls participated in a case-control design under natural circumstances in a field study to investigate plasma vasopressin levels 3 times daily, circadian motor activity, and the 24-hour periodicity of body temperature for 5 consecutive 24-hour periods. Temperature measurements consisted of at least 5, but mostly 6 or more measurements every 24 hours. 22% of the patients, but none of the controls, lacked 24-hour periodicity of body temperature. In melancholic patients increased vasopressin levels in plasma correlated with a weak 24-hour periodicity of body temperature. The role of vasopressin is discussed in the light of the present findings. (PsycINFO Database Record (c) 2000 APA, all rights reserved)