[Seasonal variations in dexamethasone suppression test in psychiatric patients]

The existence of seasonal variations in the dexamethasone suppression test (D.S.T.) has been remarked. In a sample of 345 patients with affective symptomatology and various psychiatric diagnostics, patient with major depression have higher non suppression levels in spring and winter; a similar but stronger seasonal variations is observed in patients with melancholic and patients with psychotic syndrome showed a similar tendency. In patients with diagnostics different from depression (dementia, schizophrenia, mania, anxiety disorders), the non suppression level is higher in winter. Some similarities with the contributions of other authors are observed but in general disagreements are more frequent, which suggests us the influence of latitude and geo-climatic changes, since the seasonal variability can not be explained by means of seasonal changes in demographic or clinical variables, as diagnostic or psychiatric syndrome.