Characteristics of High-Cost Beneficiaries of Prescription Drugs in Kazakhstan: A Cross-Sectional Study of Outpatient Data from 2022.

Background and Objectives: Limited information is available regarding the distribution of increasing pharmaceutical expenditures within large representative samples of national populations globally. The aim was to investigate the distribution of pharmaceutical costs in outpatient treatment and analyze the primary characteristics of users of expensive drugs within the healthcare system of Kazakhstan. Methods: This study utilized data from the Information System for Outpatient Drug Supply, which includes nationally representative data from all regions of Kazakhstan, covering both rural and urban populations. The key explanatory variables in this study included age, gender, number of prescribed medications, disease categories based on ICD-10 codes, and insurance coverage status. These variables were selected to capture demographic, clinical, and healthcare access factors influencing prescription drug costs. In total, 2.2 million people, who were prescribed outpatient medications were included. High-cost users (HCUs) were characterized as individuals whose prescription drug expenses ranked within the highest 5%. Results: The distribution of pharmaceutical costs exhibits significant discrepancy, with 5% of the population receiving prescription drugs covered by the state budget and social medical insurance fund contributing to nearly three-quarters of all costs. Notably, these HCUs tended to be younger than low-cost drug users. HCUs, on average, consumed a greater quantity of medications compared to non-HCUs. Among children, the top diseases contributing to high costs were rare hereditary diseases and malignancies, while in adults, cancer and diabetes were the primary cost drivers. Conclusion: There is a concentration of public drug program spending within a small percentage of beneficiaries with high drug costs in Kazakhstan. This discovery offers valuable insights for shaping policies tailored to this specific population, aiming to mitigate escalating costs and enhance the optimal use of medications.