Safety events in kidney transplant recipients: results from the folic Acid for vascular outcome reduction in transplant trial.
BACKGROUND
Kidney transplant recipients are at increased risk for adverse safety events related to their reduced renal function and many medications.


METHODS
We determined the incidence of adverse safety events based on previously defined Agency for Healthcare and Research Quality (AHRQ) International Classification of Diseases-9 (ICD-9) code-derived patient safety indicators (PSI) in the Folic Acid for Vascular Outcome Reduction in Transplant trial participants who had a hospitalization stratified by tertiles of estimated glomerular filtration rate (GFR). We also examined the frequency of Micromedex defined two precautionary drug-drug interactions, and two medications whose use may be contraindicated because of reduced GFR from the Folic Acid for Vascular Outcome Reduction in Transplant trial medication thesaurus at baseline, and annually among 4,110 participants. Logistic regression was used to examine the relationship between patient safety events and baseline demographic and clinical variables at a participant level. Event rates were estimated at participant and visit levels.


RESULTS
Of the 2,514 patients with a hospitalization, 978 (38.9%) experienced an AHRQ PSI. Factors which were associated with more common AHRQ PSI included: U.S. location, history of cardiovascular disease or diabetes, and lower tertile of estimated GFR. At a participant level, 2,524 of the 4,110 participants (61.4%) were taking calcineurin inhibitor and statin, 378 (9.2%) were taking azathioprine and an angiotensin-converting enzyme inhibitor, 171 (12.9%) were taking a sulfonylurea), 45 (3.4%) were taking metformin despite a baseline GFR below 40 mL per min per 1.73 m.


CONCLUSIONS
We conclude that patient safety events are not uncommon in kidney transplant recipients. Careful monitoring is necessary to prevent adverse outcomes.
1 Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD. 2 Department of Biostatistics, University of North Carolina, Chapel Hill, NC. 3 Department of Pharmacy, University of Maryland Medical Center, Baltimore, MD. 4 Rhode Island Hospital, Brown University School of Medicine, Providence, RI.
Matthew R
MR
Weir
Lisa
L
Gravens-Muller
Nadiesda
N
Costa
Anastasia
A
Ivanova
Wana
W
Manitpisitkul
Andrew G
AG
Bostom
Clarissa J
CJ
Diamantidis
D000328:Adult; D065095:Calcineurin Inhibitors / Q000494:pharmacology; D004347:Drug Interactions; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage*; D005919:Glomerular Filtration Rate; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008687:Metformin / Q000494:pharmacology; D008875:Middle Aged; D061214:Patient Safety
D065095:Calcineurin Inhibitors; D008687:Metformin; D005492:Folic Acid