Abstract 9: Post-Discharge Use of Statin and Lipid Testing After Myocardial Infarction

Abstract

Background: The 2013 ACC/AHA cholesterol guidelines recommend high intensity statin use for all post-myocardial infarction (MI) patients, instead of treating to a low density lipoprotein cholesterol (LDL-C) goal on follow-up lipid testing. We examined whether high intensity statin use was common in U.S. practice prior to these guideline updates. Methods: We linked the ACTION Registry-GWTG to Medicare data and evaluated 11,046 post-MI patients aged ≥65 years discharged alive on a statin from 347 hospitals between 2007 and 2009. Rates and dosing of lipid therapy as well as follow-up lipid testing within 90 days after discharge were studied. Multivariable logistic regression was used to evaluate the association of lipid testing with 1-year statin use and intensity. Results: Only 21% of MI patients were discharged on a high intensity statin. By 90 days post-MI, 44% (n=4,884) of patients underwent lipid testing. Among patients discharged on low/moderate intensity statins, 43% underwent lipid testing within the next 90 days, and 49% of patients discharged on high intensity statins received lipid testing within 90 days. Rates of lipid testing did not differ substantially between patients with LDL-C ≥100 mg/dL vs. <100 mg/dL during the MI hospitalization (47% vs. 43%). Among MI patients alive at 1 year, 74% remained on a statin, yet only 14% were on a high intensity statin. Only 4% of those discharged on low/moderate dose statin had been titrated up to a high intensity statin. Patients undergoing lipid testing within 90 days of discharge were more likely to be on a statin at 1 year (Figure, adjusted OR 1.17, 95% CI 1.07-1.29), and more likely to have their statin therapy intensified (adjusted OR 1.92%, 95% CI 1.52-2.41). Conclusion: Prior to the 2013 ACC/AHA cholesterol guideline updates, only 1 in 5 MI patients were discharged on high intensity statin therapy. Although follow-up lipid testing was associated with both higher rates of statin persistence to one year and increased likelihood of statin intensification, it was performed in only a minority of patients. The new cholesterol guidelines may promote more aggressive lipid management and cardiovascular risk reduction by eliminating treatment dependence on follow-up lipid testing.