[Seasonal pattern in hospital admissions due to bipolar disorder in Santa María, Córdoba, Argentina].

Introduction: The purpose of this research is to establish if there is a seasonal pattern in hospitalizations due to affective episodes of bipolar disorder in Hospital Colonia Santa María, Córdoba, Argentina, between 2000-2003.

Materials And Methods: The affective episodes considered were those which required patient hospitalization with bipolar disorder diagnosis (ICD-10). Medical histories were analyzed subsequently, according to the DSM-IV criteria. The episodes considered were those with hospitalization during all the pathobiographical history of the patient.

Outcome: 84 affective episodes were considered. 43 were maniac (51%), 20 were depressive (24%), 15 were mixed (18%) and 6 were hypomaniac (7%). A statistically significant association was found (p0.001) between affective episodes of bipolar disorder and the season of the year, with a seasonal pattern of mania-hypomania in summer and depression in winter. Mixed episodes were distributed more consistently in the year with a peak in summer.

Conclusion: In this research a relationship is established between bipolar disorder and seasonal nature in hospitalizations.