Poverty and Common Mental Disorders in Developing Countries

Article excerpt

Voir page 613 le resume en francais. En la pagina 613 figura un resumen en espanol.

Introduction

In making choices for health funding in low-income countries, policy-makers and donor agencies are guided by epidemiological evidence that indicates the burden of disease on the poor. There is a large body of evidence from industrialized countries demonstrating an association between poverty and risk for common mental disorders. This paper reviews the evidence from developing countries and explores the processes that may explain the poverty--risk relationship.

Common mental disorders are depressive and anxiety disorders that are classified in ICD-10 (1) as: "neurotic, stress-related and somatoform disorders" and "mood disorders". The public health significance of mental and behavioural disorders is demonstrated by the fact that they are among the most important causes of morbidity in primary care settings and produce considerable disability (2, 3). Definitions of poverty vary depending on the social, cultural and political systems in a particular region and according to the user of the data. Poor people's definitions reveal that poverty is a multidimensional social phenomenon (4). From an epidemiological perspective, poverty means low socioeconomic status (measured by social of income class), unemployment and low levels of education (5); these are the definitions used in this review.

Methods

A search of the MEDLINE database (using PubMed) and reports on global mental health (2, 6, 7) was carried out to identify papers reporting studies that met the following criteria: the studies were based in community settings; the countries were classified as middle- or low-income by the World Bank (8); and the methodology included both a measure of mental disorders and a measure of poverty. Because of overlap between diagnostic subgroups of common mental disorders (9), epidemiological research often describes rates of common mental disorders as a single outcome; this is the outcome chosen for this review (with the exception of studies where the overall rate was not reported). In addition, articles exploring the relationship between poverty and mental health were reviewed to describe the mechanisms through which poverty and common mental disorders were related.

Results

The epidemiological evidence

There were 11 eligible studies (see Table l) from six countries in Africa (Lesotho and Zimbabwe), Asia (Indonesia and Pakistan) and Latin America (Brazil and Chile). All studies used random or total sampling of the eligible population. All were "stand-alone" studies--not part of a multinational study--and the measures were validated for the local settings. The median prevalence rates of common mental disorders varied from 20% to 30%. Ten studies showed a statistically significant relationship between prevalence and indicators of poverty, the most consistent relationship being with low educational levels. A number of other indicators were used to assess poverty, including low income, lack of material possessions, lack of employment, and housing difficulties, Irrespective of which indicator was used, statistically significant associations were evident; the one study that did not show any association (flora Lesotho) only published data on associations with specific diagnostic categories of common mental disorders.

Mechanisms of relationship

The explanatory models of persons suffering from common mental disorders have been described in a number of studies, in all of which poverty and socioeconomic problems have been cited as one of the most important factors causing emotional distress (21-23). While individual perceptions of illness are not evidence of a causal association, the universal nature of perceptions can be considered as cultural validation of the epidemiological association reported in the studies reviewed.

Income

The studies reviewed do not permit an analysis of correlation of absolute levels of income and common mental disorders, because average indicators of income for countries do not indicate the true levels in the populations being studied. …