Pre-pandemic inequalities in the burden of disease: a Scottish Burden of Disease study

BackgroundHealth inequalities in Scotland are well documented, including the contribution of different causes to inequalities in mortality. Our aim was to estimate inequalities within a burden of disease framework, accounting for both premature mortality and the effects of morbidity, to understand the contribution of specific diseases to health inequalities prior to the COVID-19 pandemic. MethodsDisability Adjusted Life Years (DALYs) for 70 individual causes of disease and injury were sourced from the Scottish Burden of Disease Study. Area-level deprivation was measured using the Scottish Index of Multiple Deprivation. Inequalities were measured by the range, Relative Index of Inequality, Slope Index of Inequality, and attributable DALYs were estimated by using the least deprived decile as a reference. ResultsThe overall disease burden was double that in the most deprived areas (50,305 vs 20,955 DALYS per 100, 000), largely driven by inequalities in premature mortality. The rate in the most deprived decile was around 48% higher than the mean population rate (RII = 0.96), with 35% of DALYs attributed to differences in area-based deprivation. Many leading causes of disease burden in 2019 - heart disease, drug use disorders, lung cancer and COPD - were also the leading drivers of absolute and relative inequalities in the disease burden. ConclusionOur study evidences the extent of the stark levels of absolute and relative inequality prior to the COVID-19 pandemic. Given pre-pandemic stalling of mortality trend improvements and widening health inequalities, and the exacerbation of these caused by COVID-19, urgent policy attention is required to address this.