Drug-related Problems and their Predictors among Breast Cancer Patients Receiving Chemotherapy in National Cancer Institute, Malaysia

Breast cancer patients receiving chemotherapy are at high risk of drug-related problems (DRPs), as it is estimated that around 5-10% of hospital admissions are due to DRPs. Breast cancer management is a leading cause of these DRPs in which the drug toxicity is considered as the main cause that makes DRPs very prevalent. Hence, this study aimed to assess DRPs and their predictors among breast cancer patients receiving chemotherapy at the National Cancer Institute (IKN), Malaysia. Breast cancer patients with any stage and type aged >= 18 years and receiving chemotherapy between January and December 2017 were included. DRPs were classified according to a modified form of the Pharmaceutical Care Network Europe (PCNE). Statistical analysis was done by Statistical Package for Social Science (SPSS) software version 24. For categorical data, the Chi-squared test was used to determine the association of patients' characteristics and the occurrence of DRPs. A p < 0.05 was assumed as statistically significant among the obtained results. Overall, 100 patients were included in the study. The majority was Malays 59 (59%) and aged between 25-67 years. A total of 157 DRPs were identified in 78 patients, translating to a prevalence of 78%. Adverse drug reactions (ADRs) were the most common DRPs (47.8%). The most frequent ADR was neutropenia which encountered in 50 patients with prevalence 14.6% of the total ADRs followed by chemotherapy induced nausea and vomiting (CINV) 42 (12.5%). Other DRPs such as drug-drug interactions, drug selection and drug dosing were less common. It was predicted with increasing the number of co-morbidities, DRPs were more likely to occur (OR = 2.279, 95%, CI 1.098-4.730, p = 0.027). DRPs were common in breast cancer patients receiving chemotherapy. The predominant proportion of DRPs was ADRs. Number of co-morbidities was a predictor of the DRPs among the studied cohort of the patients.