Evaluation of medication therapy complexity in cancer patients

The increasing number of medications due to cancer-specific therapies and other treatments for comorbidities complicates patients' medication therapies and this complexity leads to drug-related problems. The aim of this study was to evaluate the complexity of medication therapy in adult cancer patients hospitalized in a medical oncology ward using the Medication Regimen Complexity Index (MRCI), to determine the effect of complexity on patients' adherence and perceived medication burden, and to identify and prevent drug-related problems. The prospective, cross-sectional study (June 2022 – April 2023) was conducted in the medical oncology department of a University Oncology Hospital and 147 patients were included. The MRCI score at discharge [median (interquartile range): 15.0 (11.0 – 22.0)] was higher than the MRCI score at admission [median (interquartile range): 11.0 (7.0 – 15.0)] (p<0.001). As a result of the patient education given by the multidisciplinary team before discharge, an increase was observed in the treatment adherence of the patients (p=0.003). Complexity was found to be higher in patients who had more negative perceptions about their medication, in patients who reported that their daily life were significantly affected by their medication, and in patients who perceived more significant burden when complex instructions for medication use were evident (p<0.001).A total of 149 drug-related problems were determined; 144 recommendations were proposed for these problems, 83.3% of the recommendations were accepted. It is seen that when patient monitoring is provided by clinical pharmacists in cancer patients, whose medication treatments are complex, drug-related problems can be clearly identified and patients' treatment can be optimized and medication adherence can be increased. In conclusion, considering the complexity of medication in the monitoring of cancer patients and evaluating the complexity of medication from the patients' perspective may contribute to the improvement of multidisciplinary health services.