Division of Pharmaceutical Evaluation and Policy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
Ann Pharmacother. 2009 Jan;43(1):36-44. doi: 10.1345/aph.1K671. Epub 2009 Jan 6.
Multiple measures of adherence have been reported in the research literature and it is difficult to determine which is best, as each is nuanced. Occurrences of medication switching and polypharmacy or therapeutic duplication can substantially complicate adherence calculations when adherence to a therapeutic class is sought.
To contrast the Proportion of Days Covered (PDC) adherence metric with 2 variants of the Medication Possession Ratio (MPR, truncated MPR).
This study was a retrospective analysis of the North Carolina Medicaid administrative claims data from July 1999 to June 2000. Data for patients with schizophrenia (ICD-9-CM code 295.xx) who were not part of a health maintenance organization, not hospitalized, and not pregnant, taking at least one antipsychotic, were aggregated for each person into person-quarters. The numerator for PDC was defined as the number of days one or more antipsychotics was available and the MPR numerator was defined as the total days' supply of antipsychotics; both were divided by the total days in each person-quarter. Adherence rates were estimated for subjects who used only one antipsychotic, switched medications, or had therapeutic duplication in the quarter.
The final sample consisted of 25,200 person-quarters from 7069 individuals. For person-quarters with single antipsychotic use, adherence to antipsychotics as a class was: PDC 0.607, truncated MPR 0.640, and MPR 0.695 (p < 0.001). For person-quarters with switching, the average MPR was 0.690, truncated MPR was 0.624, and PDC was 0.562 (p < 0.001). In the presence of therapeutic duplication, the PDC was 0.669, truncated MPR was 0.774, and MPR was 1.238 (p < 0.001).
The PDC provides a more conservative estimate of adherence than the MPR across all types of users; however, the differences between the 2 methods are more substantial for persons switching therapy and prescribed therapeutic duplication, where MPR may overstate true adherence. The PDC should be considered when a measure of adherence to a class of medications is sought, particularly in clinical situations in which multiple medications within a class are often used concurrently.
在研究文献中已经报道了多种药物依从性测量方法，很难确定哪种方法最好，因为每种方法都有其细微差别。当寻求治疗类别依从性时，药物转换和多种药物治疗或治疗重复的发生会极大地复杂化依从性计算。
将比例天数覆盖（PDC）依从性指标与药物持有率（MPR）的 2 种变体（截断 MPR）进行对比。
这是一项对北卡罗来纳州医疗补助管理索赔数据的回顾性分析，时间范围为 1999 年 7 月至 2000 年 6 月。将未参加健康维护组织、未住院且未怀孕的精神分裂症患者（ICD-9-CM 代码 295.xx）的数据汇总到每个患者的季度中。PDC 的分子定义为一种或多种抗精神病药物可用的天数，MPR 的分子定义为抗精神病药物的总供应天数；两者均除以每个患者季度的总天数。对于该季度仅使用一种抗精神病药物、药物转换或治疗重复的患者，估计其依从性。
最终样本包括 7069 名患者的 25200 个患者季度。对于仅使用单一抗精神病药物的患者季度，抗精神病药物类别的依从性为：PDC 为 0.607，截断 MPR 为 0.640，MPR 为 0.695（p<0.001）。对于药物转换患者，平均 MPR 为 0.690，截断 MPR 为 0.624，PDC 为 0.562（p<0.001）。在存在治疗重复的情况下，PDC 为 0.669，截断 MPR 为 0.774，MPR 为 1.238（p<0.001）。
在所有类型的使用者中，PDC 提供了比 MPR 更保守的依从性估计值；然而，在治疗转换和规定的治疗重复的患者中，这两种方法之间的差异更大，其中 MPR 可能夸大了真实的依从性。当寻求药物类别依从性的衡量标准时，应考虑 PDC，特别是在经常同时使用类内多种药物的临床情况下。
Zotero 插件