Molfenter Todd D, Bhattacharya Abhik, Gustafson David H
Center for Health Enhancement Systems Studies (CHESS), Madison, WI, USA;
Patient Prefer Adherence. 2012;6:643-51. doi: 10.2147/PPA.S34711. Epub 2012 Sep 6.
Current medication-adherence predictive tools are based on patient medication-taking beliefs, but studying past behavior may now be a more explanatory and accessible method. This study will evaluate if past medication-refill behavior for a statin regimen is more predictive of medication adherence than patient medication-taking health beliefs.
This prospective longitudinal study was implemented in a national managed care plan in the United States. A group of 1433 statin patients were identified and followed for 6 months. Medication-taking health beliefs, collected from self-reported mail questionnaires, and past medication-refill behavior, using proportion of days covered (PDC), were collected prior to 6-month follow-up. Outcomes were measured using categorical PDC variable (of adherence, PDC ≥ 85%, versus nonadherence, PDC < 85%), with model fit estimated using receiver operator characteristic analysis.
The area under the receiver operator characteristic curve for past behavior (A(z) = 0.78) was significantly greater (P < 0.05) than for patient health beliefs (A(z) = 0.69), indicating that past prescription-refill behavior is a better predictor of medication adherence than prospective health beliefs. Among health beliefs, the factor most related to medication adherence was behavioral intent (odds ratio, 5.12; 95% confidence interval, 1.84 to 15.06). The factor most strongly related to behavioral intent was impact of regimen on daily routine (odds ratio, 3.3; 95% confidence interval, 1.41 to 7.74).
Electronic medical records and community health-information networks may make past prescription-refill rates more accessible and assist physicians with managing medication-regimen adherence. Health beliefs, however, may still play an important role in influencing medication-taking behaviors.
当前的药物依从性预测工具是基于患者的服药信念，但研究过去的行为现在可能是一种更具解释力且更易采用的方法。本研究将评估他汀类药物治疗方案过去的药物续方行为是否比患者的服药健康信念更能预测药物依从性。
这项前瞻性纵向研究在美国的一项全国性管理式医疗计划中实施。确定了一组1433名他汀类药物患者并随访6个月。在6个月随访前，通过自我报告的邮寄问卷收集服药健康信念，并使用覆盖天数比例（PDC）收集过去的药物续方行为。使用分类PDC变量（依从性，PDC≥85%，与不依从性，PDC<85%）测量结果，使用受试者工作特征分析估计模型拟合度。
过去行为的受试者工作特征曲线下面积（A(z)=0.78）显著大于（P<0.05）患者健康信念的曲线下面积（A(z)=0.69），表明过去的处方续方行为比前瞻性健康信念更能预测药物依从性。在健康信念中，与药物依从性最相关的因素是行为意图（比值比，5.12；95%置信区间，1.84至15.06）。与行为意图最密切相关的因素是治疗方案对日常生活的影响（比值比，3.3；95%置信区间，1.41至7.74）。
电子病历和社区健康信息网络可能使过去的处方续方率更易获取，并协助医生管理药物治疗方案的依从性。然而，健康信念在影响服药行为方面可能仍发挥着重要作用。
