Decomposition of Socioeconomic Inequality in Catastrophic Health Care Expenditure among Households Benefited from Inpatient Services: Evidence from Iran

Background: Evidences showed that the incidence of catastrophic health expenditure is unequally distributed among disadvantaged populations. The present study has tried to explain the contributors of this unfair inequality in Hamadan, Iran.Methods: The target population was households that utilized inpatient services in hospitals of Hamadan. A proportional stratified random sampling method was used to determine study sample (N= 770). The associated factors of catastrophic health expenditure were estimated using logistic regression analysis. The inequality of catastrophic health expenditure was measured by concentration index and explained by decomposition analysis. The data were analyzed by using STATA version 12.Results: The key determinants of catastrophic health expenditure were poor economic status, lower household size, lack of supplementary insurance and the number of hospitalizations. The overall concentration index of catastrophic health expenditure in Hamadan was -0.163 (95% CI: -0.242 to -0.083). Household economic status (63.60%) and household size (39.90%) were considered as the first and the second largest contributors of catastrophic health expenditure inequality, respectively.Conclusion: It is demonstrated that catastrophic health expenditure inequality in Iran could be explained by the factors beyond the health sector scope. Hence, future policy efforts need to consider both health system factors and the factors beyond the health system to eliminate catastrophic health spending burden and its inequality.