Poverty, inequality and the treated incidence of first-episode psychosis

Abstract

It is now commonly accepted that a range of psychosocial and environmental factors interact with genetic vulnerability in the genesis of psychotic illness. The aim of this study was to investigate whether measures of poverty and income inequality impact upon the treated incidence of first-episode psychosis (FEP) in the District of Umgungundlovu, South Africa. Clinical and demographic data was collected from hospital records on all people aged 15-49 years from the District who presented to psychiatric services with FEP (DSM IV criteria) during 2005 (n = 160). All incident cases were grouped by municipality according to their recorded address. Measures of poverty and income inequality were calculated for each of the seven municipalities using data from the Statistics SA online database for the National Census 2001. Correlations were performed using SPSS to determine the relationships between treated incidence of FEP and poverty and inequality indices per municipality. There was a significant positive relationship between treated incidence and Inequality Index (Partial correlation coefficient 0.840; P = 0.036) and a non-significant negative relationship between treated incidence and Poverty Measure per municipality (Partial correlation coefficient -0.660; P = 0.154). These findings remained significant after adjusting for gender, age, ethnicity, urbanicity and employment status. Importantly, these results were not adjusted for individual level poverty. These findings lend support, in an African context, to increasing evidence that social, economic and political factors such as poverty and income inequality "shape both the landscape of risk for developing (psychosis) and the context in which health-care is provided" (Kelly in Soc Sci Med 61:721-730, 2005). These complex environmental factors appear to impact on the development and course of psychotic illness.