Types of medication errors in North Carolina nursing homes: a target for quality improvement.

BACKGROUND: Medication errors are an important problem in nursing homes, but little is known about the types of medications involved in errors in this setting. Gaining a better understanding of the types of medications commonly involved in medication errors in nursing homes would be an important step toward quality improvement.
OBJECTIVES: This study sought to describe the types of medication errors most frequently reported to a statewide repository by North Carolina nursing homes. We also examined whether nursing homes reporting an error involving a drug on the updated Beers list of medications considered potentially inappropriate for use in the elderly were likely to report a greater number of medication errors or more harmful medication errors compared with nursing homes that did not report such an error.
METHODS: Medication errors were defined as preventable events that had the potential to cause/lead to or actually caused/led to inappropriate medication use or patient harm. We analyzed summary reports of medication errors submitted to the State of North Carolina by licensed nursing homes for the 9-month period from January 1, 2004, to September 30, 2004, using a Web-based reporting system. Drugs commonly involved in medication errors were summarized for all nursing homes in the state. Errors involving medications on the updated Beers list also were identified. Nursing homes were profiled and compared according to the type of medication error and whether the error reached the patient and/or caused harm.
RESULTS: Among the 384 licensed nursing homes included in our analysis, 9272 medication errors were reported. The specific medication involved was documented for 5986 of these errors. The medications most commonly involved in an error were lorazepam (457 errors [8%]), warfarin (349 [6%]), insulin (332 [6%]), hydrocodone and hydrocodone combinations (233 [4%]), furosemide (173 [3%]), and the fentanyl patch (150 [3%]). The medication errors disproportionately included central nervous system agents (16%) and analgesics (11%). Medications considered potentially inappropriate in the elderly were frequently involved in the reported errors (10% of all reported errors), with the greatest number of such errors associated with lorazepam (457 [8%]), alprazolam (130 [2%]), and digoxin (74 [1%]). Nursing homes reporting potentially inappropriate drugs among their 10 most common medication errors also reported a significantly greater mean number of errors compared with nursing homes that did not report such errors (26.9 vs 17.6, respectively; P < 0.001), as well as a significantly greater number of errors that reached the patient (6148 vs 1393; P < 0.001).
CONCLUSION: Based on the experience in North Carolina, quality improvement efforts in nursing homes should focus on the medications commonly involved in errors and should continue to discourage or closely monitor the use of medications considered potentially inappropriate in the elderly.