Season of birth variations in dimensions of functioning evaluated by the diagnostic interview for borderline patients

In view of recent reports showing that cerebrospinal fluid (CSF) levels of monoamine metabolites exhibit season of birth variations, and that they are also associated with section II (impulse action patterns) of the diagnosti c interview for borderline patients (DIB), we analyzed two samples of data to investigate the relationship between the season of birth and the DIB. Th e first sample comprised 202 patients participating in psychobiological res earch in Stockholm, and the second sample comprised 130 patients who had co mmitted suicide in Vasterbotten in northern Sweden. Those with intermediate score for section II (impulse action patterns) were significantly more lik ely to have been born during the season October to January in the pooled da ta, and this tendency persisted in separate analyses for the two samples an d for the two diagnostic groups mood disorders and schizophrenia, respectiv ely. Those with high score for section IV (psychosis) were significantly mo re likely to have been born during February to April in the pooled sample a nd in the nonschizophrenic group. In the group with schizophrenia, those bo rn during February to April had significantly high scores for section III ( affects). These results throw further light on the role of season of birth in suicidology and in psychiatric morbidity. Copyright (C) 2000 S. Karger A G, Basel.