Influence of heredity, sex and season on the type of episode of bipolar disorder

Abstract

peer reviewedThe aim of this work was to investigate if sex, age, family history, season and hypothyroidism have any influence on the type of episodes (manic, depressive, mixed) seen in bipolar patients. This retrospective study concerns a sample of 208 patients with a diagnosis of bipolar disorder (type I or II), who were admitted in one of two psychiatric centers between July 1996 and June 2000. The sex-ratio was 2.8 females for 1 male. Sex, family history and hypothyroidism were not associated with any type of episode. A higher percentage of depressive episodes was observed in the patients who were older than 50 and the average age of depressive patients was higher than that of other patients. There was no seasonal pattern in this study and the season did not influence the type of episode. The results indicate no influence of sex, season, family history and hypothyroidism on the type of episode presented. On the opposite, age seems to favour depression episode