Copeptin during rest and exercise in major depression

BackgroundHigh vasopressin levels and a correlation between vasopressin and cortisol has been observed in patients with depression. The aim was to assess copeptin, the c-terminal of provasopressin, and the association between cortisol, adrenocorticotropic hormone (ACTH) and copeptin in patients with depression. Secondly, to examine the copeptin response to acute exercise and aerobic training.MethodsCopeptin, ACTH, and cortisol were measured in 111 patients with depression and 57 controls at rest. Copeptin was also measured during exercise. The depressed patients were subsequently randomized to an aerobic training intervention or an exercise control intervention.ResultsThe plasma level of copeptin in depressed subjects was 5.14 pg/ml (IQR 3.4-8.4) and 4.82 pg/ml (IQR 2.8-7.5) in healthy controls (p=.66). The association between copeptin and cortisol was.02 (95% CI -.44 to.48; p=.93) and the association between copeptin and ACTH was -.06 (95% CI -.17 to.05; p=.27). All associations were independent of depression status (p=.15). Aerobic exercise training did not influence copeptin levels at rest (p=.09) or the response to acute exercise (p=.574). Copeptin decreased at rest in response to aerobic training in participants with high compliance to the exercise intervention (p=.04).LimitationsWe did not measure plasma osmolality, which is a possible confounder in this study.ConclusionsCopeptin levels are not elevated or associated to ACTH or cortisol in depressed patients. Aerobic exercise training decreased copeptin levels in high attenders only. This study does not support a role of copeptin or vasopressin in depression.