Clinical and economic outcomes associated with medication errors in kidney transplantation

Abstract

Background and objectives: Modern immunosuppressant regimens have significantly decreased acute rejection rates, but may have increased the risk of graft loss driven by adverse drug reactions (ADRs) and medication errors (MEs). The objectives of this study were to determine the incidence and risk factors for MEs and ADRs and determine the association between transplant outcomes and these events.

Design, setting, participants, & measurements: This was a post hoc analysis of a prospective, randomized trial that included patients aged>18 years that received a solitary renal transplant at an academic medical center recruited between March 2009 and July 2011. Patients were divided into groups based on developing a clinical significant ME (CSME), defined as a significant ME that contributed to a hospital admission.

Results: The mean study follow-up was 2.5 ± 0.7 years. There were a total of 233 MEs and 327 ADRs in the 200 patients included in the analysis, with 64% of the cohort experiencing at least one ME and 87% experiencing an ADR; 23 patients (12%) experienced a CSME. Patients that experienced CSMEs had a trend toward more post-transplant readmissions (median 1 [interquartile range (IQR), 0-5] versus 0 [0-2]; P=0.06), higher costs for readmissions (median $18,091 [IQR, $3023-$56,268] versus $0 [$0-$15,991]; P<0.01), and overall length of stay (median 5.0 days [IQR, 2.0-14.0] versus 0.0 days [IQR, 0.0-5.5]; P<0.01) after the CSME event. CSME patients were also more likely to experience graft failure (22% versus 10%; P=0.05).

Conclusions: Significant MEs commonly occur in renal transplant recipients and are associated with an increased risk of deleterious clinical outcomes, including subsequent hospital days, costs, and graft loss.

Keywords: acute rejection; drug interactions; drug nephrotoxicity; kidney transplantation.

Figure 1.

Kaplan–Meier survival curves for graft loss. The top Kaplan–Meier analysis displays the graft survival curves for the CSME and non-CSME cohorts. The bottom Kaplan–Meier analysis displays the graft survival rates for those with and without acute rejection. The number of patients at risk for events during follow-up for each analysis is displayed below the corresponding survival curves. CSME, clinically significant medication error.