Drug-Related Problems and Hospital Admissions in Cardiac Transplant Recipients

Background: Drug-related problems (DRPs) in the general population account for 15% of all hospital admissions, of which approximately 30% are preventable. Cardiac transplant patients may be at increased risk for DRPs because of their complicated medication regimens that include drugs with a narrow therapeutic index. Objective: To determine the incidence and praventability of DRPs causing hospital admission in cardiac transplant patients at a single institution. Methods: Between November 2009 and January 2010, a prospective longitudinal study investigated the incidence and preventability of DRPs in a single cardiac transplant center. Three independent reviewers used validated scoring systems to determine the incidence and preventability of drug-related hospital admissions. DRPs were classified by type, pharmacologic class, and impact on length of stay. Results: During the 3-month study period, 48 cardiac transplant patients were hospitalized. DRPs accounted for 40% (19/48) of these admissions and 58% (11/19) were adjudicated to be preventable. Common DRPs included supratherapeutic (32%) and subtherapeutic (16%) dosage, adverse drug reaction (32%), drug interaction (5%), and nonadherence (5%). Pharmacologic classes implicated included immunosuppressant (63%), antimicrobial (11%), electrolyte/fluid (11%). and anticoagulant (5%). Average length of stay in drug-related compared to non-drug-related admissions was 11.4 versus 8.5 days (p = 0.458). When annualized, 44 hospitalizations or 500 hospital days may have been prevented. Conclusions: Hospital admissions following cardiac transplantation are often drug related (40%) and preventable (58%). Incorporating this insight into the multidisciplinary transplant team may improve outcomes, assist in meeting national quality mandates by the United Network for Organ Sharing and Centers for Medicare Services, and lead to new benchmarks for transplant centers.