Statin discontinuation is common but may have no clinical basis, study indicates

Many patients discontinue statins because of reported adverse events, but most can tolerate the drugs long-term if therapy is restarted, according to a new study.

Researchers performed a retrospective cohort study to examine the reasons for statin discontinuation, particularly statin-related adverse events, in routine care. Adults seen at practices affiliated with Brigham and Women's Hospital and Massachusetts General Hospital in Boston who were prescribed a statin between Jan. 1, 2000, and Dec. 31, 2008, were included. Data on reasons for statin discontinuation were obtained from electronic medical records and electronic clinician notes. The study appeared in the April 2 Annals of Internal Medicine.

The study included 107,835 patients, 38.7% of whom had a history of coronary artery disease. Atorvastatin was the most common statin taken. A total of 57,292 patients discontinued statins at least temporarily, and of these, 39,568 (69.1%) had a reason for the discontinuation recorded in the electronic medical record. A documented statin-related event occurred in 18,778 patients (17.4%); of these, 11,124 discontinued statin therapy at least temporarily, and of that group, 6,579 were rechallenged with a statin over the next year. Most of the patients who were rechallenged (92.2%) were still on statin therapy 12 months after the statin-related event took place. A total of 2,721 patients were challenged with the same statin they had discontinued, and of these, 1,295 were receiving the same drug 12 months later, 996 at the same or a higher dose.

The authors acknowledged that their study was retrospective, used secondary data that could have been incomplete or misinterpreted, and examined patients affiliated with only two academic medical centers, among other limitations. However, they concluded that while patients often report statin-related events and discontinue statin therapy because of them, most are able to restart statins and remain on them long-term. “This suggests that many of the statin-related events may have other causes, are tolerable, or may be specific to individual statins rather than the entire drug class,” they wrote.

An accompanying editorial pointed out that part of the problem with statin therapy is that it is lifelong. “This is a tall order for many persons, and it is not surprising that discontinuation rates are relatively high,” the editorialist wrote. He suggested that two questions be considered when developing strategies to improve statin adherence: Why do patients discontinue them, and in what proportion do real side effects, or statin intolerance, prevent therapy continuation? Since treatment guidelines are becoming “increasingly ‘aggressive’” in recommending statins for primary prevention, the editorialist wrote, adherence will probably continue to be problematic. “With little doubt, good adherence to preventive therapies carries the potential for greatly reducing population prevalence of atherosclerotic cardiovascular disease,” he wrote. “Better strategies to promote statin adherence are essential to realizing this potential.”