Common Drugs Most Frequent Culprits in Emergency Hospitalizations

Adverse drug events that lead to emergency hospitalization of older adults represent a direct consequence of clinical care and can be attributed to a few run-of-the-mill prescription drugs, according to a study (abstract) in the New England Journal of Medicine, or NEJM.

Using data gathered by the National Electronic Injury Surveillance System-Cooperative Adverse Drug Event Surveillance project from 2007 through 2009, the study authors estimate that nearly 100,000 cases of emergency department visits and subsequent emergency hospitalizations due to adverse drug events occur each year in the United States. Of those hospitalizations, some two-thirds result from use of a few common medications.

Specifically, the authors estimate that warfarin accounts for 33,171, or 33 percent, of such emergency hospitalizations in older adults, while insulins, oral antiplatelet agents and oral hypoglycemic agents are responsible for another 38 percent. Few hospitalizations -- 1.2 percent -- are thought to result from use of high-risk drugs, and only 6.6 percent are likely attributable to potentially inappropriate drugs.

The report's authors characterize this incidence as "representing a substantial burden." For example, an estimated 21,010 hospitalizations for warfarin-related hemorrhage alone cost "probably hundreds of millions of dollars annually." Oral antiplatelet agents, the authors estimate, account for an additional 13,263 hospitalizations.

"The substantial contribution that (antiplatelet agents) make to hospitalizations in older adults is a reminder of the need for careful consideration of risks and benefits for individual patients and counseling about early recognition of hemorrhagic symptoms," say the authors.

In the case of warfarin, evidence shows that anticoagulation-management services can help improve anticoagulation control and reduce both thromboembolic and bleeding events. For oral antiplatelet agents, which are not as amenable to dose adjustment and monitoring, the strategy is less clear.

According to Doug Campos-Outcalt, M.D., M.P.A., of Phoenix, who is associate chair for the department of family and community medicine at the University of Arizona College of Medicine, several steps can be taken to reduce these types of events, including establishing a medical home for patients to avoid uncoordinated care among specialists.

"Make sure patients are not on medications they do not need or that will not really help them, monitor medication use carefully, and instruct patients not to make changes in medications or take new OTC (drugs) without discussing the change with you," he says.

The study also notes that the high number of hypoglycemia-related hospitalizations (an estimated 10,656 each year) suggests that current guidelines and performance measures may not reflect "optimal diabetes management" for all patients.

Again, says Campos-Outcalt, it comes down to knowing the individual patient. Overall, the AAFP does not favor a "strict 'tight' approach" to blood glucose management because it is not appropriate for everyone.

"We are in favor of a flexible approach, depending on patient circumstances," he notes.