Socioeconomic inequality in overweight in Sub Saharan Africa.

Objective Rationale for this study is the worldwide obesity epidemic, increasingly affecting the low income world. Also Sub Saharan Africa is nowadays confronted with a rising prevalence of overweight. The aim of this study was to investigate and explain the socioeconomic gradient in overweight in Sub Saharan Africa. Methods Datasets were derived from Demographic Health Surveys (DHS) carried out by the National Demographic Health program. To explore a recent time trend in the prevalence of overweight in Sub Saharan African countries, it has been decided to include data generated between 2004 and 2011. Countries included are Rwanda, Uganda, Senegal, Zimbabwe, Lesotho, Ethiopia and Malawi. The dataset contains a sample size of 39770 females. The primary outcome is overweight measured by the body mass index (BMI>25). The Erreygers corrected concentration index (CC) will be used to measure the absolute wealth related inequality in overweight. The inequalities in overweight are explained by a decomposition analysis. As the study aims to explain the trend in wealth related inequality in overweight, the change in the CCs has also been decomposed. Results Apart from Senegal and Lesotho, all countries experienced a positive trend in the prevalence of overweight. Lesotho, Zimbabwe and Senegal show the highest percentages of overweight. Overweight appears to be most concentrated among the most wealthy groups in all countries during both periods. Countries with the lowest Gross Domestic Product (GDP) show a positive trend in overweight inequality. Contrary, a negative trend is observable in more developed countries. The most important explanatory factors of inequality are respectively wealth, urbanization and education. The degree in which these factor contribute to the change in overweight inequality differs by country. However, education seems to become more important with a higher stage of economic development. Conclusion As overweight in Sub Saharan Africa is nowadays mostly concentrated among the rich it could be questioned whether the current socioeconomic distribution of overweight is a major problem for health policy makers. However it might be assumed that the socioeconomic distribution of overweight will shift towards the poor in the future. Wealth, urbanization and education should be taken into consideration as important contributors to the socioeconomic inequality in overweight. Understanding the socioeconomic gradient in overweight will guide policymakers in addressing this problem in Sub Saharan Africa.