Department of Health Services Research, The University of Texas MD Anderson Cancer Center, 1400 Pressler St., Unit 1444, Houston, TX, 77030, USA.
Division of Outcomes Research and Quality, Department of Surgery, College of Medicine, Penn State University, Hershey, PA, USA.
Drugs Aging. 2019 Dec;36(12):1111-1121. doi: 10.1007/s40266-019-00715-3.
Prescription drug costs have been rising rapidly in the USA, contributing to the persistent problem of cost-related medication nonadherence (CRN) among older Medicare beneficiaries. Given the importance of CRN and the negative outcomes associated with it, it is important to examine the factors that affect CRN. This study aims to estimate the factors influencing CRN among older Medicare beneficiaries and to rank their relative contribution in explaining CRN.
We used a 2015 Medicare Current Beneficiary Survey linked to Medicare claims data to identify older Medicare beneficiaries aged 65 years and over. Multivariate logistic regression was performed to identify factors associated with CRN. Factors included in the regression analyses were based on a conceptual framework adapted from Piette et al., including main effects (financial factors and regimen complexity) and contextual factors (sociodemographic, lifestyle and health factors). Dominance analysis was conducted to determine their relative importance in predicting CRN.
Our study sample included 4427 older Medicare beneficiaries, 13.43% of whom reported CRN. For main effects, drug coverage and regimen complexity were significantly associated with CRN. Compared to beneficiaries with public coverage, those with private drug coverage were less likely to report CRN while those without drug coverage were more likely to report CRN. Having more than two monthly prescriptions was also associated with higher CRN. Significant contextual factors included age, activities of daily living limitations, perceived health status, cancer, rheumatoid arthritis, non-rheumatoid arthritis, depression, and lung disease. Dominance analysis showed drug coverage was the most influential factor in explaining CRN, after which age, ADL limitations, and depression ranked in sequence.
These findings can help policy makers understand the relative importance of factors affecting CRN and identify the most important areas for intervention to improve CRN.
在美国，处方药费用迅速上涨，导致老年医疗保险受益人持续存在与费用相关的药物不依从（CRN）问题。鉴于 CRN 的重要性及其相关的负面后果，研究影响 CRN 的因素非常重要。本研究旨在估计影响老年医疗保险受益人的 CRN 的因素，并对其解释 CRN 的相对贡献进行排名。
我们使用 2015 年医疗保险当前受益人调查与医疗保险索赔数据相关联，以确定 65 岁及以上的老年医疗保险受益人。采用多变量逻辑回归来确定与 CRN 相关的因素。回归分析中包含的因素基于 Piette 等人的概念框架，包括主要效应（财务因素和方案复杂性）和情境因素（社会人口统计学、生活方式和健康因素）。进行优势分析以确定它们在预测 CRN 方面的相对重要性。
我们的研究样本包括 4427 名老年医疗保险受益人，其中 13.43%报告存在 CRN。对于主要效应，药物覆盖范围和方案复杂性与 CRN 显著相关。与具有公共覆盖范围的受益人相比，具有私人药物覆盖范围的受益人报告 CRN 的可能性较小，而没有药物覆盖范围的受益人报告 CRN 的可能性较大。每月有超过两种处方也与更高的 CRN 相关。显著的情境因素包括年龄、日常生活活动受限、感知健康状况、癌症、类风湿性关节炎、非类风湿性关节炎、抑郁和肺部疾病。优势分析显示，药物覆盖范围是解释 CRN 的最具影响力的因素，其次是年龄、ADL 限制和抑郁。
这些发现可以帮助政策制定者了解影响 CRN 的因素的相对重要性，并确定改善 CRN 的最重要干预领域。
