Drug interactions among older adults followed up in a comprehensive medication management service at Primary Care

ABSTRACT Objective: To estimate the prevalence of drug interactions and associated factors among older adults followed up in a Comprehensive Medication Management Service at Primary Care. Methods: Firstly, the Beers criteria 2015 was used to define drug interactions; later, drug interactions proposed by Dumbreck for patients with diabetes, depression, and heart failure were evaluated. The associated factors were assessed by univariate (Pearson's χ2) and multivariate analyses (logistic regression). The significance level of 5% was set for all analyses. Results: The mean age of the studied population was 70.2±7.8 years; 52.2% were between 60 and 69 years, and 61.3% were female. Among the older adults, 94.5% used two or more drugs (condition for the occurrence of drug-drug interaction). The prevalence of drug interaction according to the Beers criteria was 4.9%. After multivariate analysis, diseases of the central nervous system, arrhythmia, number of medications, and female sex were positively associated with drug interaction. The prevalence of drug interaction according to Dumbreck was 27.2%. After multivariate analysis, the number of medications, the presence of heart failure, and Charlson comorbidity index greater than 1 were conditions positively associated with drug interactions. Conclusion: The holistic and individualized approach used in comprehensive medication management services for older patients is important, considering the prevalence of drug interactions and the need to minimize adverse events.

摘要
研究目的：本研究旨在评估基层医疗综合药物管理服务随访的老年人群中药物相互作用的患病率及其相关影响因素。
研究方法：首先采用2015版Beers标准（Beers criteria）定义药物相互作用；随后针对合并糖尿病、抑郁症及心力衰竭的患者，评估由Dumbreck提出的药物相互作用判定方案。采用单因素分析（Pearson χ²检验）与多因素logistic回归分析对相关影响因素进行筛选，所有统计分析均设定5%为显著性检验水准。
研究结果：纳入研究的老年人群平均年龄为70.2±7.8岁；其中52.2%的受试者年龄介于60~69岁，女性占比61.3%。94.5%的老年人同时使用2种及以上药物（此为发生药物-药物相互作用的前提条件）。依据Beers标准判定的药物相互作用患病率为4.9%；经多因素分析发现，中枢神经系统疾病、心律失常、用药数量以及女性性别与药物相互作用呈正相关。依据Dumbreck判定标准的药物相互作用患病率为27.2%；经多因素分析显示，用药数量、心力衰竭病史以及查尔森合并症指数（Charlson comorbidity index）大于1均为药物相互作用的正向相关因素。
研究结论：鉴于老年人群药物相互作用的患病率现状与降低不良事件发生的临床需求，为老年患者提供综合药物管理服务时，需采用整体性与个体化相结合的干预方案。