The occurrence of suicide in severe depression related to the months of the year and the days of the week

The purpose of the present study was to investigate the distribution of suicide during the months of the year and the days of the week in severe depression. A total of 1206 in-patients rated at discharge from the Department of Psychiatry, Lund, Sweden, on a multiaxial diagnostic schedule received the diagnosis severe depression/melancholia between 1956 to 1969. When followed up to 1998, a total of 114 depressed patients had taken their own life. Out of these, 98 patients appeared to have a primary depression. The monthly distribution of suicides showed a significant peak in October/November for men (41 % of all male suicides). No correlation with the onset of depression could be detected. Furthermore, there was a preponderance of suicide on Sundays for both sexes (31 % of all suicides).