Urbanicity and Psychosis: Is there a Connection? A Comparative Study between an Urban and Rural Area in Portugal

Abstract

Introduction: Studies about urbanicity and psychosis show contradictory results. In northern European countries and China there is a positive relationship; in southern European and underdeveloped countries, a significant difference between rural and urban rates of psychosis has not been found. Methods: We carried out a 5‐year retrospective observational study, with patients admitted to two inpatient units for first‐episode psychosis (FEP), in a rural area (Évora) and an urban area (Lisbon). We excluded affective or organic psychosis. Socio‐demographic and clinical data were extracted and analyzed.Results: The prevalence of FEP was the same for both areas (42/100 000 inhabitants), with a predominance of unemployed (63%) and lonesome individuals (81% in Évora versus 72% in Lisbon). The mean age was similar (Évora 43.4 years old; Lisbon 41.4 years old). Lisbon had a greater diversity of nationalities (16.3% vs 4.6%) and a higher rate of psychotic disturbance due to substance use (26.5% vs 21.6%). The most prevalent diagnosis in the Lisbon was unspecified psychotic disorder (UPD) (34.7%), while in Évora it was delusional disorder (DD) (21.5%) and acute andtransient psychotic disorder (21.5%). DD was a prevalent diagnosis in both areas, affecting mainly women and those with a higher median age. Duration of untreated psychosis (DUP) of less than 1 month was higher in Lisbon (24.5% vs 4.5%), but there was a high prevalence of DUP of more than 2 years in both samples (20.4% vs 23.1%). Discussion: The mean age of FEP was higher than in other studies, which may translate a significant prevalence of DD or reflect a higher DUP. A reduced DUP of less than 1 month in the rural area can be explained by greater isolation of the population, lower health literacy or better integration of patients in the community. The prevalence of UPD was higher in the urban area, possibly due to different forms of registration or a lower DUP. Conclusion: Our results are in line with studies reported in southern European countries, where no association was found between psychosis and urbanicity, and further studies are needed to elucidate this issue.