The Evolution of Inequality in mortality between disease. \'A case study of Ghana\'

Introduction Health Inequalities are a global issue which affect all countries both wealthy and less wealthy alike. Efforts to address disparities in health often poses a challenge as this is one of the most relevant issues faced in population health. Mortality which is one of the measurable aspects of health often differs across diseases as some are more difficult to treat. In Ghana, out of 246 diseases, 3 diseases namely malaria, LRI, and ischemic heart diseases accounted for 27% of total deaths in 2015. The aim of this study is to investigate inequality in mortality between diseases which can provide an insight into the likelihood of having access to treatment depending on disease severity. Methods Data was obtained from the Institute of Health Metrics and Evaluation’s Global Health data exchange. Data was on Ghana for the years 1990, 2000 and 2015. This was to identify how the inequality has changed over time. It included information on 246 diseases in relation to their mortality and DALYs. Mortality and DALYs were used to rank disease severity. Diseases that accounted for less than 0.001% of total deaths were not used in the analysis. The Gini and Erreygers index and corresponding Lorenz and concentration curves were used to measure and display the level of inequality. The change in the Gini index over the years was decomposed with the Jenkins and Van Kerm decomposition to analyze whether it was due to progressivity or re-ranking. Results When disease severity is ranked by mortality, a decline is observed in inequality in mortality between diseases over the years. The decomposition of the change showed that major part is due to concentration of mortality towards relatively less severe diseases .i.e. increases in mortality were more substantial among less severe diseases. However, when diseases are ranked by DALYs, an increase was observed in the mortality between diseases over time. Splitting the samples, the direction of change differs by gender and age categories. Conclusion In sum, the choice of variable used to quantify disease severity produces different conclusions. Ranking disease severity by mortality, we may conclude that there is an increased likelihood of having access to treatment especially for severe diseases. On the contrary when DALYs are used, widening inequalities are observed. The implication is that diseases that have high disabling effect may have been neglected compared to those that have high mortality effect. Additionally, differences in mortality across diseases have become smaller.