Interventions Appear Related to Reduced Risk of Adverse Drug Events

Interventions that included enhanced communication between a pharmacist and patients and physicians and computerized organization of a patient’s medications appear to be associated with a decreased risk of adverse drug events, according to two articles appearing in the April 27 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Adverse drug events (ADEs) and medication errors (MEs) are common and costly threats to the quality of care. Such drug-related problems are common in outpatients in the United States and added together with other drug-related problems cost $77 billion to $177 billion annually, according to background information in the first article. While the incidence of these events among inpatients is well recognized, such events often go unnoticed in the outpatient setting and are more difficult to measure. Inpatient studies suggest that a pharmacist may help reduce these events, but little is known regarding the effect on outpatients.

Michael D. Murray, Pharm.D., M.P.H., of the University of North Carolina at Chapel Hill, and colleagues examined the effect of a pharmacist intervention on ADEs and MEs in outpatients with heart failure or hypertension by combining data from two randomized controlled trials. The pooled analysis included 800 outpatient cases of hypertension divided into complicated (n = 535; patients had heart failure or other cardiovascular complications) and uncomplicated (n = 265). Computer programs examined one-year electronic record data to identify events classified as ADEs and preventable or potential ADEs. Study participants were an average of 59 years old; 71 percent were women.

The intervention was provided by specifically trained pharmacists, who spent more of their time instructing patients on the appropriate use of their medications, drug monitoring, and communication with patients’ primary care physicians, with the goal of improving adherence and medication use.

There were a total of 210 ADE or ME events, with fewer of these events occurring in the intervention group. The five most common events, occurring in a total of 68 participants, included receipt of a prescription for a drug that should be avoided in elderly patients; vaginal candidiasis (yeast infection) resulting from an orally administered antibiotic; an increase in serum creatinine level associated with a medication; inadequate monitoring after prescribing; and prescription of multiple acetaminophen products. Compared with the control group, the intervention group had a 34 percent lower risk of any event, including a 35 percent lower risk of ADEs and a 37 percent lower risk of MEs.

“In conclusion, this post hoc analysis of a pharmacist intervention to improve medication use in adult outpatients suggests a lower risk of adverse drug events and medication errors. Further studies are needed to confirm this finding,” the authors write.

Arch Intern Med. 2009;169[8]:757-763.