Regional disparities in infant mortality in Bulgaria (2000–2023): impact of ethnic inequality

Abstract Background Bulgaria continues to report one of the highest infant mortality rates (IMR) in the European Union, despite a decline from 14.8‰ in 1990 to 4.9‰ in 2023. National averages mask regional disparities, especially in areas with high Roma populations and socioeconomic disadvantage. This study aimed to assess the magnitude of regional differences in IMR and the impact of ethnic-related socio-economic factors. Materials and methods This ecological time-trend study analysed regional IMR across Bulgaria's NUTS-2 regions from 2000 to 2023, using data on births and infant deaths from the Bulgarian National Statistical Institute. IMR and rate ratios (RR) were calculated to compare regional disparities at the start and end of the study period. Bivariate correlations and linear regression were applied to assess associations between IMRs and percentage of Roma population, poverty rate, unemployment, female educational attainment, regional GDP and paediatrician density. Results Regional disparities in IMRs widened significantly between 2000 and 2023. In 2023, the IMR ratios between regions with highest and lowest rates increased from 2.0 to 3.0, and for foetal mortality, it rose from 2.1 to 3.4. Regional differences in IMR and foetal mortality were strongly correlated with the percentage of Roma population (r = 0.841, p = 0.036) and the proportion at risk of poverty (r = 0.892, p = 0.042). IMRs were negatively correlated with the proportion of women with university education (r=-0.829, p = 0.042). Regression analysis identified the percentage of Roma population and the poverty rate as independent predictors of foetal mortality (R²=0.868, F = 9.972, p = 0.047). Conclusions Regional disparities in IM in Bulgaria are closely linked to ethnic and socioeconomic inequalities, particularly affecting regions with large Roma populations. Addressing these disparities requires inclusive public health policies improving child health services and reduction of ethnic and social inequities Key messages • Ethnic inequalities impact regional health disparities, both remain hidden in routine national health monitoring. • The focus on ethnic inequalities is a productive public health research approach.