Assessment of Potential Drug-Drug Interaction with Antiepileptic Drugs in Ambulatory Elderly Patients with Epilepsy in Taiwan

• Main Authors: Mei-WenWang, 王美文
• Other Authors: Yea-Huei Kao Yang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/82156587497883963559

碩士 === 國立成功大學 === 臨床藥學與藥物科技研究所 === 101 === Background: Because some antiepileptic drugs (AEDs) have great involvements of hepatic enzymes and can affect metabolic processes of drugs, potiential drug-drug interaction (DDI) is one of the main concerns in epileptic treatment. Elderly patients who often take concomitant medications were especially at high risk of drug interactions. However, limited information was available from previous studies about AED-DDIs in this group. Factors associated with higher risk of AED-DDIs have not been identified. Purpose: The study aimed to evaluate the degree and associated risk factors of drug–drug interactions with antiepileptic drugs ( AED-DDIs) in elderly patients with epilepsy in Taiwan. Method: A retrospective cohort study was conducted by using Taiwan’s National Health Insurance Research Database (NHIRD). Patients aged 65 or older with epilepsy defined by ICD-9 code 345 from 2005 to 2009 were included. From the date of AEDs initiation, patients were followed until the end of one year, discontinuation, switch/add-on, or disenrollment. Medications with AED-DDIs were defined by Drug Interaction Facts 2013, Lexi-Comp OnlineTM, and Micromedex. DDI score were calculated as primary indicator of AED-DDIs degree, defining as days of medication with AED-DDIs supplied divided by follow-up days. Multivariate linear regression models were used to identify risk factors associated with AED-DDIs. Result: A total of 5,785 elderly patients with epilepsy were identified with mean age was 76.61 (±7.15) years and 55.9% were male. The mean DDI score of all patients was 0.68 (±0.80), and the highest score were found in patient receiving phenytoin (0.94) and carbamazepine (0.99). Individuals receiving traditional AEDs [β=0.72; 95% CI: 0.65, 0.78], being cared by specialist other than neurologist [β=0.07; 95% CI: 0.03, 0.12], receiving more than 6 drugs for chronic conditions [β=0.20 (95% CI: 0.15, 0.25)], and comorbid condition of stroke [β=0.08 (95% CI: 0.04, 0.13)], hypertension [β=0.22 (95% CI: 0.18, 0.26)], ischemic heart disease [β=0.10 (95% CI: 0.06, 0.15)] and chronic obstructive pulmonary disease [β=0.05 (95% CI: 0.01, 0.10)] were associated with higher DDI score. Conclusion: A high degree of AED-DDIs in elderly patients with epilepsy warrants clinical attentions. Numbers of risk factors were identified and can be strong grounds for future investigations and policy decisions.