Drug-related problems vary with medication category and treatment duration in Taiwanese heart failure outpatients receiving case management

BACKGROUND/PURPOSE: Heart failure (HF) patients are at high risk of having drug-related problems (DRPs). We aim to describe the frequency, types, and temporal occurrence of DRPs in Taiwanese HF outpatients receiving case management. METHODS: In this study, we included 141 patients from HF clinics in three hospitals in Taiwan from October 2008 to December 2010. Nurse case managers at each of the participating sites registered case report forms (CRFs) for patients during clinic visits. DRPs were classified using the Pharmaceutical Care Network Europe Foundation (PCNE) classification system and documented by pharmacists after reviewing CRFs and participating in multidisciplinary team discussions. RESULTS: For 141 clinic participants, the average duration of medication use was 17 months, and 796 DRPs were reported. The DRPs most frequently recorded were the need for laboratory tests (32.7% of total DRPs), followed by potential interaction (29.6%), nonallergic side effects (13.3%), and insufficient awareness of health and disease (9.5%). The drugs most frequently causing a DRP were angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers, diuretics, warfarin, spironolactone, and β-blockers. The incidence rates of total DRPs was maximal during the initial 3 months of medication treatment, whereas the incidence rates of each category of DRPs showed multiform changes over time among various drug classes. CONCLUSION: In Taiwan where the clinical pharmacist system is not well organized, HF outpatients still had a high prevalence of DRPs despite intensive monitoring by nurse case managers. Clinical pharmacists play critical roles in detecting potential DRPs during long-term medication treatment for this population.