To determinate the prevalence of several mental disorders and its relationship with sex among patients admitted in a Psychiatric Unit.

The sample included all patients hospitalized in a Psychiatric Unit at the Hospital “Virgen de las Nieves” in the city of Granada (southern Spain), during the time period between 1998 and 2006 (n=1873). The tenth version of international classification diseases (ICD-10) was used to classify the mental disorders.

The principal diagnoses were psychotic disorders (36%), affective disorders (30%), substance-related disorder (8%) and personality disorder (7%). The prevalence of men was 57% and the prevalence of women was 43%. Male sex was significantly associated with substance-related disorder (OR=3.2; IC 95 %: 2.1-4.9), schizophrenia (OR=3.7; IC 95 %: 2.7-4.9) and mental retardation (OR=1.2; IC 95 %: 2.4-4.0). Female sex was significantly associated with bipolar disorder (OR=1.7; IC 95 %: 1.3-2.3), dysthymia and other depressive disorders (OR=2.4; IC 95 %: 1.9-3.1) and neurotic disorders (OR=2.3; IC 95 %: 1.4-3.7).

According with literature (Vogel et al, 1997) the principal diagnoses among patients hospitalized were psychotic disorders, followed by affective disorders. Previous epidemiological studies have shown similar prevalence of bipolar disorder among both sexes (Kessler et al, 1997; Kawa et al, 2005). Nevertheless, among patients with bipolar disorder who need hospitalization may be more women.