If Statins Are So Good, Why Do People Stop Taking Them?

Statins are one of the most widely prescribed classes of drugs, used in secondary prevention of cardiovascular disease (CVD) and for patients with diseases considered high-risk CVD equivalents (eg, diabetes and chronic kidney disease), as well as for the primary prevention of CVD. In fact, indications for statins have extended their use to the perioperative period. Prescribing statins for high-risk individuals undergoing non-cardiac surgery reduces cardiovascular morbidity and mortality.¹

Taking statins, however, is not as much an issue it seems as discontinuing them.

Why do people stop taking these lifesaving and life-sustaining drugs? Some fear side effects, others perceive side effects (direct-to-consumer marketing doesn’t help in this regard), and for some cost may be an issue (especially among the uninsured or underinsured).² There also may be individuals who do not grasp the benefits of statin therapy, are never committed to the treatment in the first place, or who do not return to their care provider for refills. Something I never realized is that some people are just not attuned to taking drugs daily for a lifetime and as a result become nonadherent.² Of course there is a critical subset of patients who discontinue as a direct result of statin side effects. Physicians and patients alike are wary of muscle problems, as well as less frequently mentioned issues such as liver injury or recent questions regarding an enhanced risk for diabetes.
 
A study just published in theAnnals of Internal Medicineprovides necessary insight into the question of why folks discontinue. Zhang and coworkers³ chose a cohort of 107,825 individuals for whom statins had been prescribed. The first statin prescribed was one of the single-agent formulations available-atorvastatin, fluvastatin, lovastatin, pravastatin, rosuvastatin, or simvastatin. Remarkably, 57,292 of these persons discontinued the prescribed statin at least temporarily.³ Statin-related events were documented for 18,778, or 17.4%, of these patients. The incriminating drug-related events consisted of the usual suspects, that is myalgia/myopathy (4.7%), rhabdomyolysis (0.006%), creatine kinase elevations 3 to 10 times upper limit of normal (0.092%), and hepatobiliary problems (0.70%). There were some unusual suspects as well, including memory problems (0.06%) and reproductive and breast disorders (0.09%).² The remaining events comprise a list of reported problems that is long and suspicious for events that are not a result of medication use. 

The important primary care lesson is contained in the statin rechallenge category. Of the 11,124 persons who had statins discontinued for any period of time, 6579 were rechallenged over the ensuing year. A provocative 92.2% of these individuals were still taking a statin 12 months after the initial statin-related event. Even more interesting, among the 2721 patients who were rechallenged with the same statin, 1295 continued it and 996 of them were taking the same or a higher dose. The other individuals in this particular group (n=1426) benefitted from a switch to another statin-a good strategy to promote adherence.
 
The study authors summarize their findings this way, “. . . most patients who are rechallenged [with statins] can tolerate statins 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.” Just because a patient has an event while taking statins does mean these important drugs are out of the picture.

Please-develop strategies to follow and improve statin adherence in your practice.        
  
References:

1. Chan WW, Wong GT, Irwin MG. Perioperative statin therapy. Expert Opin Pharmacother. 2013 Mar 25; [Epub ahead of print]. (Abstract)
2. Grundy SM. Statin discontinuation and intolerance: the challenge of lifelong therapy. Ann Intern Med. 2013;158:562-563. (Preview)
3. Zhang H, Plutzky J, Skentzos S, et al. Discontinuation of statins in routine care settings: a cohort study. Ann Intern Med. 2013;158:526-534. (Abstract)