Structural violence and schizophrenia : psychosocial, economic and cultural impacts on the onset of psychoses.

Abstract

Schizophrenia is a common and serious mental disorder affecting approximately 1% of the population (WHO, 1973). That genetic and other developmental factors give rise to a predisposition or vulnerability to schizophrenia is well recognized. However, the role of the environment in conferring risk for the disorder is now indisputable. Psychosocial, economic and cultural factors all impact on risk as evidenced by recent epidemiological studies reporting variable incidence in relation to factors including unemployment, urbanicity, migration and trauma. Complex gene-gene and gene-environment (GxE) interactions lie at the origin of this common human disorder and account for the diversity of epidemiological findings and clinical presentations that we encounter in research and clinical practice. This thesis comprises of six research papers and includes data from two separate studies of first-episode psychosis (FEP) conducted in KwaZulu-Natal, South Africa. The first study (Chapter 2) explored the impact of income inequality and poverty on the incidence of FEP and the results provide the first evidence for an association between increasing income inequality and increased incidence of FEP. The second study (Chapter 3) investigated the impact of a number of psychosocial, economic and cultural factors on the clinical presentation of FEP. Previous experiences of trauma were associated with positive and affective symptoms at psychosis onset, while cannabis use was associated with clinical features of FEP that previously have been associated with better outcome. Cultural factors such as spiritual attributions of cause and previous consultation with traditional healers may delay entry to psychiatric care and thereby negatively impact on prognosis of FEP. Chapter 4 addresses the issue of how the environment acts through GxE interactions to modify risk and alter the clinical presentation and course of schizophrenia. In this paper, new epidemiological findings are integrated with an evolutionary genetic theory of schizophrenia. In Chapter 5, I present a human rights perspective on the inequities and inequalities that characterize the lives of those with serious mental disorders such as schizophrenia, resulting from psychosocial, political, economic and cultural forces in the environment. The concluding chapter draws all of the data together, highlights key findings and conclusions from the thesis, addresses weaknesses and limitations of these conclusions and identifies priority areas for future research in this field.