Statin intolerance may increase risk of coronary heart events
Statin intolerance is likely to elevate the risk for recurrent myocardial infarction (MI) and coronary heart disease (CHD) events but not all-cause mortality, a recent study suggests.
“In a national cohort of Medicare beneficiaries hospitalized for MI, statin intolerance was common in the year after initiation of therapy,” researchers said. “Medicare beneficiaries with statin intolerance had an increased risk for recurrent MI and CHD events.”
Of the 105,329 Medicare beneficiaries who began a moderate- or high-intensity statin dosage after hospitalization for MI between 2007 and 2013, 1,741 patients (1.65 percent) had statin intolerance and 55,567 patients (52.8 percent) had high statin adherence. A total of 4,450 recurrent MIs, 6,250 CHD events and 14,311 deaths occurred during a median follow-up of 1.9 to 2.3 years.
“The incidence rates of recurrent MI and CHD events were higher among Medicare beneficiaries with statin intolerance than among their counterparts with high statin adherence,” researchers said. “Statin intolerance was not associated with an increased risk for all-cause mortality. Results were consistent in sensitivity analysis that included down-titration of statin intensity as an indicator of intolerance.”
Beneficiaries with statin intolerance, compared with those with high statin adherence, had a 36-percent higher rate of recurrent MI (41.1 vs 30.1 per 1,000 person-years, respectively), 43-percent higher rate of CHD events (62.5 vs 43.8 per 1,000 person-years) and 15-percent lower rate of all-cause mortality (79.9 vs 94.2 per 1,000 person-years). [J Am Coll Cardiol 2017;69:1386-1395]
Comparing beneficiaries with statin intolerance vs those with high statin adherence, the multivariate-adjusted hazard ratios were 1.50 (95 percent CI, 1.30 to 1.73) for recurrent MI, 1.51 (1.34 to 1.70) for CHD events and 0.96 (0.87 to 1.06) for all-cause mortality.
The study reinforces the need for patients with CHD to maintain high statin adherence, according to researchers, adding that statin intolerance may increase the risk for MI and CHD events through the subsequent discontinuation of treatment, low adherence or use of low-intensity dosages.
“The findings of the current study clearly show that there are serious morbid consequences to the elusive disorder of statin intolerance and support an aggressive management strategy for clinicians treating these anguished and challenging patients,” Dr Steven E. Nissen from the Cleveland Clinic Foundation in the US said in an accompanying editorial. [J Am Coll Cardiol 2017;69:1396-1398]
“We must make every possible effort to administer evidence-based doses of statins to patients with appropriate clinical indications for treatment. Additional efforts to study the phenomenon of statin intolerance are critically important and must include development of alternative therapies for treating the substantial cardiovascular morbidity associated with this disorder,” he added.
Further studies are warranted to understand the mechanisms responsible for recurrent coronary events among patients with statin intolerance and to develop alternative interventions to attenuate this risk, researchers said.
Statin intolerance is defined as “down-titrating statins and initiating ezetimibe therapy, switching from statins to ezetimibe monotherapy, having International Classification of Diseases, 9th revision, diagnostic codes for rhabdomyolysis or an antihyperlipidemic adverse event, followed by statin down-titration or discontinuation, or switching between ≥3 types of statins within 1 year after initiation,” according to researchers.
On the other hand, high statin adherence over the year following hospital discharge is defined as “proportion of days covered ≥80 percent,” they added.