Wealth-related Inequality in Utilization of Antihypertensive Medicines in Iran: an Ecological Study on Population Level Data

BACKGROUND: We aim to evaluate the trend of national and sub-national (provincial) utilization pattern of antihypertensive medicines in the Iranian population in the past decade and evaluate whether there is any wealth-related inequality in utilization of these medicines among different provinces. METHOD: Either fixed effect or random effect linear panel data model was used to check the effect of wealth index on utilization of all antihypertensive medicines and each class, adjusting for other covariates including years of schooling, urbanization, mean age, and food type of provinces. The principal component analysis was applied to make summery measures for covariates using available national datasets. RESULTS: The effect of wealth category on the utilization of all antihypertensive medicines among Iranian provinces was positive and significant (0.84; 95% CI: 0.09, 1.59). Accordingly as subgroup analysis, in BBs and CCBs classes, the effects of wealth category on utilization of medicines were positive and significant (0.36; 95% CI: 0.12, 0.60 and 0.27; 95% CI: 0.07, 0.40, respectively). However in ACEIs and Diuretics classes, the effects of wealth category were positive but not significant. In ARBs class, the effect of wealth on utilization was negative and not significant (-0.04; 95% CI: -0.27, 0.18). CONCLUSION: According to this study, an inequality could be observed in Iran related to wealth category in utilization of total antihypertensive medicines between provinces.