Characteristics of unplanned hospital admissions due to drug-related problems in cancer patients

Background: Studies have examined drug-related problems (DRPs) that have led to hospital admissions in the general population. However, there is a lack of information on the characteristics of DRPs in the cancer population. Objective: The objective of this study was to investigate the type, causality, severity, and preventability of DRPs that result in unplanned hospitalizations among cancer patients. Methods: This was a prospective, cohort study conducted in two oncology wards between July and December 2012. All patients who were diagnosed with solid tumor or lymphoma and required unplanned hospitalization were included. The incidence of DRPs among hospital admissions was captured, and the nature of the DRPs (causality, severity, and preventability) was characterized. Results: There were 1,299 admissions and 1,275 were eligible for analysis. Among the 1,275 eligible admissions, 158 (12.4 %) were considered to be associated with a DRP. In the 158 admissions associated with DRPs, 164 DRPs were found. The majority of the DRP-related admissions were adverse drug reactions (ADRs) (n=155/164, 94.5 %), probable (n=98, 59.8 %), moderately severe (n=155, 94.5 %), and probably or definitely preventable (n=86, 52.4 %). Most patients with DRPs recovered and were discharged. Febrile neutropenia was the most common adverse drug reaction, and drug combinations involving antihypertensives and long-term corticosteroids raised the risks for potential drug-drug interactions among patients with cancer. Conclusion: The incidence of DRP-induced unplanned hospital admissions was 12.4 % among cancer patients. Approximately half of these were preventable events.