University of Missouri-Kansas City School of Pharmacy, Kansas City, Missouri 64108-2718, USA.
Clin Ther. 2011 May;33(5):608-16. doi: 10.1016/j.clinthera.2011.04.022.
High prescription copayments may create barriers to care, resulting in medication nonadherence. Although many studies have examined these associations in commercially insured patients with chronic disease, few have examined β-blocker effects in heart failure patients.
Associations between β-blocker prescription copayment levels and medication nonadherence were examined within commercially insured beneficiaries with a diagnosis of heart failure.
Heart failure patients were identified as those with at least 1 inpatient claim or 2 outpatient claims with an associated International Classification of Diagnosis, 9th Edition (ICD-9) code of 428.x, in addition to those with at least 2 β-blocker claims. Copayment levels were defined in using $5.00 (USD) interval categories, and adherence was defined using the medication possession ratio (MPR). Ordinary least squares (OLS), fixed effects (FE), and random effect (RE) models were used to estimate associations between copayment level and MPR. Logistic regression was used to estimate the probability of nonadherence (MPR < 0.80) conditional upon copayment level. Regressions controlled for patient demographics, health status, prior hospitalizations, and concomitant medication use.
The highest β-blocker copayment level ($26+) had an average MPR that was 0.07 (95% CI, -0.11 to -0.03), 0.08 (95% CI, -0.12 to -0.04), and 0.09 (95% CI, -0.17 to -0.02) units lower than β-blocker copayment level ($0 to $1) in the OLS, RE, and FE models, respectively. Copayment levels $21-$25 and $26+ were significantly associated with an increased risk of medication nonadherence (OR = 1.64; 95% CI, 1.1-2.4; and OR = 2.5; 95%, CI 1.6-4, respectively).
Commercially insured heart failure patients aged ≥50 years who are prescribed higher costing β-blockers may have up to an average 9% decrease in annual β-blocker medication supply as well as an increased risk of nonadherence (MPR <0.80). Results need to be interpreted with caution given the potential of selection bias due to selective prescribing. Associations between copayment levels and nonadherence need to be further explored given the adverse health consequences of nonadherence to β-blockers.
高处方共付额可能会造成就医障碍，导致患者不遵医嘱用药。尽管许多研究已经在患有慢性病的商业保险患者中检验了这些关联，但很少有研究检验β受体阻滞剂在心力衰竭患者中的作用。
本研究旨在检验商业保险受益人心力衰竭患者中β受体阻滞剂处方共付额水平与用药不依从性之间的关联。
心力衰竭患者的确定标准为至少有 1 次住院或 2 次门诊就诊，且均伴有国际疾病分类第 9 版（ICD-9）编码 428.x 的相关诊断，同时至少有 2 次β受体阻滞剂的处方记录。采用 5 美元（USD）的间隔类别来定义共付额水平，采用用药持续性比率（MPR）来定义用药依从性。采用普通最小二乘法（OLS）、固定效应（FE）和随机效应（RE）模型来估计共付额水平与 MPR 之间的关联。采用逻辑回归来估计在共付额水平条件下不依从的概率（MPR<0.80）。回归分析控制了患者的人口统计学特征、健康状况、既往住院情况和伴随用药情况。
β受体阻滞剂共付额最高水平（$26+）的平均 MPR 比β受体阻滞剂共付额最低水平（$0 至$1）分别低 0.07（95%置信区间，-0.11 至-0.03）、0.08（95%置信区间，-0.12 至-0.04）和 0.09（95%置信区间，-0.17 至-0.02）。β受体阻滞剂共付额水平在$21-$25 和$26+$与药物不依从性风险的增加显著相关（OR=1.64；95%置信区间，1.1-2.4；和 OR=2.5；95%置信区间，1.6-4）。
年龄≥50 岁的商业保险心力衰竭患者，处方较高费用的β受体阻滞剂时，每年的β受体阻滞剂药物供应量可能会减少平均 9%，且不依从的风险增加（MPR<0.80）。鉴于选择性处方可能导致选择偏倚，结果需要谨慎解释。鉴于β受体阻滞剂不依从会带来不良健康后果，因此需要进一步探索共付额水平与不依从之间的关系。
