Has the prevalence, clinical presentation and social functioning of schizophrenia changed over the last 25 years? Nithsdale schizophrenia survey revisited.


BACKGROUND: Major changes in the treatment of schizophrenia have taken place in recent years, including a shift from inpatient to community care, and the introduction of second-generation antipsychotics and psychosocial interventions. Recent evidence has questioned the superiority of these interventions over older treatments. AIMS: We wished to ascertain the impact of changes in the treatment of schizophrenia in a geographically-defined area, focusing on clinical symptoms and psychosocial outcome. METHODS: In 2006, we replicated the survey carried out in 1981, identifying the population of people with schizophrenia living in Nithsdale, South-West Scotland, measuring prevalence using the 'key informant' method. We assessed their clinical and social functioning, using similar scales, and compared measures across both time periods. RESULTS: We identified 205 people with schizophrenia, a point prevalence of 3.59/1000 general population. In 2006, while fewer people experienced negative symptoms, a greater number experienced positive symptoms. There were no significant differences in the prevalence of tardive dyskinesia or Parkinsonism, though tremor was less common in the 2006 population. In 2006, there were fewer people living with a spouse/partner or parents, and fewer were in open employment in comparison to the 1981 population. The overall level of social adjustment had not changed. CONCLUSIONS: The clinical manifestation of schizophrenia appears to have changed over the last 25 years, within this geographically-defined area, the prevalence of negative symptoms having decreased, and positive symptoms seem to have increased. The level of social functioning does not appear to have changed over the last 25 years.