Prevalence of use and sources of antihypertensive medicine in Brazil: an analysis of the VIGITEL telephone survey

ABSTRACT: Objective: The prevalence of hypertension in Brazil and worldwide has been increasing in recent decades, and drug therapy is one of the strategies used to control this condition. The objective of this study was to estimate the prevalence of use and identify the sources for obtaining antihypertensive drugs in Brazil, according to sociodemographic variables, comparing three periods: 2011, 2014 and 2017. Methods: Data from individuals aged ≥20 years who reported a medical diagnosis of hypertension, interviewed by Vigitel in 2011, 2014 and 2017 were used. Frequency and prevalence of drug use in addition to the sources for obtaining medication were estimated by sociodemographic variables, with 95% confidence intervals. The differences between proportions were verified by Pearson’s chi-square test (Rao-Scott), with a significance level of 5%. Results: The prevalence of antihypertensive drug use remained stable (80%). Regarding the sources for obtaining these medicines, there was variation in the period, indicating a decrease in usage through the Brazilian Unified Health System (SUS) (44.2% in 2011; 30.5% in 2017). This decrease was accompanied with increase in PFPB (16.1% in 2011; 29.9% in 2017). The prevalence of other sources for obtaining medicine (private pharmacies/drugstores) showed stability in the period. Conclusions: The prevalence of medication use remained high and there was a change in the pattern of use according to sources, demonstrating migration between SUS pharmacies to the PFPB, and suggesting a reduction in the availability of medicines from public pharmacies universally, and for free.

摘要：
研究目的：近数十年来，巴西乃至全球的高血压（hypertension）患病率持续攀升，药物治疗是控制该病症的重要策略之一。本研究旨在结合社会人口学变量，估算巴西抗高血压药物的使用患病率，明确其获取渠道，并对比2011年、2014年与2017年三个时段的差异。
研究方法：本研究纳入2011年、2014年及2017年经Vigitel访谈的、自述经医学诊断为高血压且年龄≥20岁的个体数据。基于社会人口学变量，估算抗高血压药物的使用频率与患病率，以及药物获取渠道，并计算95%置信区间。组间比例差异采用皮尔逊卡方检验（Rao-Scott）进行验证，检验水准设定为5%。
研究结果：抗高血压药物的整体使用患病率稳定在80%。在药物获取渠道方面，不同研究时段存在显著变化：通过巴西统一健康系统（SUS）获取药物的比例呈下降趋势，从2011年的44.2%降至2017年的30.5%；与之相对，PFPB渠道的使用占比有所上升，由2011年的16.1%提升至2017年的29.9%；而其他获取渠道（私人药房/药店）的占比在研究周期内保持稳定。
研究结论：巴西抗高血压药物的使用患病率仍处于高位，且药物获取渠道的使用模式发生了转变，表现为从SUS药房向PFPB渠道迁移，这提示公共药房普遍免费提供药物的可及性有所降低。