Drug-Related Problems Among Peritoneal Dialysis Patients: A 12-Year Retrospective Cohort Study

Introduction Studies regarding drug-related problems (DRPs) can be found in other diseases, but data are lacking among peritoneal dialysis (PD) populations. Despite advancements in PD care, there remains a significant gap in understanding and addressing DRPs in the PD population. DRPs can lead to serious consequences, including medication errors, adverse reactions, and nonadherence, affecting patient outcomes and healthcare costs. Aim The aim of this study was to identify the prevalence of DRPs, types, causes, interventions performed, acceptance of interventions, and outcomes of DRPs among patients undergoing PD. In addition to this, the study sought to identify factors associated with DRPs in the PD population. Methods This single-center retrospective study recruited adult PD patients with at least one medication from January 2009 until November 2021. Pharmacy medication therapy adherence clinic (MTAC) clinical activity sheets were reviewed, and DRPs were classified based on the Pharmaceutical Care Network Europe Classification (PCNE) v9.1. The PCNE system consists of five essential domains: Problems (P), Causes (C), Interventions (I), Acceptance of the Intervention (A), and Outcomes (O). As part of the pharmacists' MTAC activities, DRPs were meticulously documented. Three pharmacists initially gathered and examined these recorded DRPs. Each identified DRP was then classified according to the type of problem, the underlying cause, any intervention performed to address the DRP, the level of acceptance, and the resulting outcome. Subsequently, these classifications were reviewed by two independent pharmacists to ensure accuracy and consistency. Results Out of 562 patients, 70.6% (n = 397) were on more than 10 drugs. Most patients (n = 520, 92.5%) had at least one DRP. From the 3,333 DRPs identified, the most common were effects of drug treatment not optimal (n = 1,595, 47.8%), followed by untreated symptoms (n = 843, 25.3%) and adverse drug events (n = 730, 21.9%). The main cause of the suboptimal treatment effect was patients' noncompliance (n = 891, 55.9%). For untreated symptoms, the main cause was no drug prescribed despite existing indications (n = 789, 93.6%). Interventions for DRPs were at either prescriber level (n = 2,064, 61.9%), patient-level (n = 1,244, 37.3%), or at other levels, such as with nurses (n = 25, 0.8%). Prescribers accepted 83% (n = 1713) of interventions suggested by pharmacists. Overall, 73.2% (n = 2,439) of DRPs were resolved. Number of medications (b = 0.223, 0.102-0.345) and number of MTAC visits (b = 0.381, 0.344-0.419) were predictive factors of the number of DRPs (p < 0.001). Conclusion There is a high prevalence of DRPs in PD patients. Pharmacists play an important role in detecting, intervening, and resolving DRPs to improve patients' outcomes.