Gender differences in patients presented with first-episode psychosis in Hong Kong

Abstract

BACKGROUND: Gender differences have been observed in psychotic disorders in terms of premorbid adjustment, illness onset, symptomatology, course and outcome. Most studies focused on schizophrenia and the samples examined were mainly recruited from subjects with chronic illness in inpatient setting. Few studies have evaluated gender differences of functional psychosis encompassing various diagnostic categories at its early illness stage in a representative sample. Thus, the aim of this study was to investigate gender differences in a treated sample of patients with first-episode psychosis. METHODS: Seven hundred (male, n = 360; female, n = 340) subjects aged 15-30 years consecutively enrolled in a territory-wide first-episode psychosis treatment program in Hong Kong from 1st July 2001 to 31st August 2003 were studied. Socio-demographic data, baseline and follow-up clinical variables, and treatment and service utilization characteristics were collected via systematic medical records review. CGI severity of illness (positive, negative and affective symptoms) and SOFAS (social functioning) were retrospectively employed on case notes in each month across the whole three-year follow-up period. Gender differences at entry and outcome were examined. RESULTS: At service entry, females had significantly longer median duration of untreated psychosis (p < 0.001). achieved higher educational level (p < 0.01) and were less likely to be a smoker (p < 0.001). Males experienced more negative symptoms (CGI, p = 0.01) and lower level of affective symptoms (CGI, p < 0.01) at baseline. No gender difference was observed in age at first presentation, age at onset of psychosis, mode of onset, baseline functioning, pre-service substance abuse and suicidal attempt. In three-year follow-up period, males had significantly more severe negative symptoms (CGI, p < 0.001) and less affective symptoms (CGI, p < 0.01), and were more likely to commit violence (p < 0.01) and to have comorbid substance abuse (p < 0.01). Females had significantly better functioning than males in follow-up interval (SOFAS, p < 0.001) and more females than males were employed in second (p < 0.01) and third year (p < 0.01) of follow-up. There was no gender difference noted in numbers and total length of psychiatric hospitalizations, numbers of relapses, service disengagement, suicidal attempt and severity of positive symptoms. DISCUSSION: Gender differences were evident in the early phase of functional psychosis since the illness onset. Males were found to have lower premorbid educational attainment, more prominent negative symptoms and less severe affective symptoms at baseline and along the course of illness, less favourable outcome with poorer psychosocial functioning and more comorbid substance abuse than females in first-episode psychosis sample. More research should be conducted to better elucidate the interplay between biological and psychosocial factors contributing to gender differences of psychotic disorders with respect to illness manifestation and trajectory. Clinically, differential needs between men and women and gender-specific therapeutic strategies need to be considered in early intervention service for first-episode psychosis.