AHA warns of drug-drug interactions with statins

Physicians typically prescribe statins to lower cholesterol and help reduce the risk of MIs and strokes. The medications have proven to work in numerous clinical trials and are cheap. Still, they are also associated with drug-drug interactions, according to a new American Heart Association (AHA) scientific statement.

The statement, which was published Oct. 17 in Circulation, recommended that physicians understand the pharmacokinetics of statins and drugs that are commonly prescribed with them. The writing group committee emphasized the need to identify drug-drug interactions early and manage them through dose adjustments, changing to safer statins or discontinuing treatment.

“Statin [drug-drug interactions] in cardiovascular patients
 are often unavoidable and should be clinically managed,” the group wrote. “Healthcare providers should be knowledgeable about the 
dose limits, adverse effects and monitoring parameters associated with these [drug-drug interactions] to minimize toxicity.”

An estimated 2.8 percent of hospital admissions occur as a direct result of drug-drug interactions, according to the researchers. The percentage is likely higher than that, though, because drug-drug interactions might be incorrectly reported as adverse drug reactions.

AHA guidelines recommend high-intensity statin therapy for patients with atherosclerotic cardiovascular disease who are 75 years old or younger and moderate- to high-intensity statin therapy for patients who are older than 75, have diabetes and familial hypercholesterolemia and a 10-year atherosclerotic cardiovascular disease risk of 7.5 percent or higher.

The writing committee examined antiarrhythmic drugs, medications used in treating congestive heart failure, antiplatelet agents and anticoagulants, immunosuppressive agents, non-statin cholesterol lowering agents and calcium channel blockers. The group evaluated data from clinical trials, case reports, prescribing information and pharmacokinetic studies.

“Healthcare providers and their patients who take statins need to be aware that these medications could interact with their other heart disease medications, such as medications to control blood pressure, treat abnormal heart rhythms, and others,” Barbara S. Wiggins, PharmD, chair of the writing committee and a clinical pharmacy specialist in cardiology at the Medical University of South Carolina, said in a news release. “While many of these drug combinations are safe, every patient is different and will tolerate medications differently. Patients need to be aware that interactions can occur and should speak to their healthcare providers about any unusual side effects or concerns.”