Effects on Hypertension Control of Distributing Essential Medicines at No Charge: A Quasi-Experimental Study In Rural Communities Of China

Background: Hypertension control is public health priority. Available and affordable medicines are regarded as important strategies for successfully controlling hypertension, but little is known about the causal effects of distributing essential medicines at no charge.  Methods: People aged above 35 with new or poorly controlled hypertension were entitled to a hypertension management pilot program in Jiaonan rural areas, Qingdao, China. After community screening, the program referring to hypertension control focused on free (Captopril, Nitrendipine, and Compound Reserpine) and self-paid antihypertensive medicines recommended by physicians, accompanied by a multi-component intervention, including physician education on mediation-taken, and health behaviors promotion. Enrolled patients were classified into three groups: non-medicine users, free-medicine users and charged-medicine users. In this quasi-experimental study, pairwise comparison of blood pressure during followed-up period in the three groups were conducted using a matched pair design with propensity score matching. Individual net effects of specific free medicine regimen were then calculated by uplift modelling.  Findings: After propensityscore matching, the control rate of blood pressure was higher for free-medicine users than non-medicine ones, and closer to that for charged-medicine users at the end of follow-up period. Judging from individual net effects, above 40% patients could benefit from these free medicines in the aspects of hypertension control. However, almost 50% had unnecessary or inappropriate medicine use.  Interpretation: Overall, provision of free essential medicine, along with corresponding follow-up management, could work to reduce blood pressure to the reference range. Essential medicines, such as Captopril, Nitrendipine, and Compound Reserpine, could be applied as options of free anti-hypertensive medicine in China. Nevertheless, individual treatment effects should be taken into consideration to figure out the optimal medicine-prescribing strategy.  Funding: National Natural Science Foundation of China and Key R & D projects of science and Technology Department of Shandong Province. Declaration of Interest: We declare no competing interests. Ethical Approval: This study was approved by the institutional ethics review board in Shandong University (No.20111126). All patients were asked to provide written, informed consent to permit the use of their data.