Statin Overuse in Cerebral Ischemia Without Indications: Systematic Review and Annual US Burden of Adverse Events

BACKGROUND: Statin agents play a major role in secondary prevention after acute cerebral ischemia (ACI) events but are not indicated in all patients with ischemic stroke and transient ischemic attack. National guidelines recommend statins for patients with ACI of large or small vessel atherosclerotic origin and without these stroke mechanisms but coexisting coronary artery disease or primary prevention indications. The potential adverse effect burden of statin overuse in the remaining ACI patients have not been well delineated. METHODS: Per Preferred Reporting Items of Systematic Reviews and Meta-Analyses guidelines, we performed systematic meta-analyses of: (1) statin randomized clinical trials to determine absolute risk increases for 6 major adverse events; (2) large clinical series to determine the proportion of ACI events due to large or small vessel atherosclerotic disease; and (3) the proportion of remaining patients with coronary artery disease/primary prevention statin indications. RESULTS: For adverse effects, data were available from 63 randomized clinical trials enrolling 155 107 patients. Statin therapy was associated with an increased risk of the occurrence of 6 conditions: diabetes, myalgia or muscle weakness, myopathy, liver disease, renal insufficiency, and eye disease. Across 55 large series enrolling 53 501 patients, the rate of ACI due to large and small artery atherosclerosis was 45.0% (large artery atherosclerosis 21.6%, small vessel disease 23.4%), the rate of remaining patients with coronary artery disease/primary prevention statin indications was 31.8%, and the rate of patients without statin indications was 23.2%. Data synthesis indicated that, in the United States, were all patients with ACI without statin indications treated with statins, a total of 5601 patients would develop needless adverse events each year, most commonly diabetes, myopathy, and eye disease. CONCLUSIONS: More than one-fifth of patients with ACI do not have an indication for statins, and statin overuse in these patients could annually lead to over 5600 adverse events each year in the United States, including diabetes, myopathy, and eye disease. These findings emphasize the importance of adhering to guideline indications for the start of statin therapy in ACI.