April 2, 2016 – Only 39 percent of patients prescribed statin and ezetimibe continued both to one year.
Ezetimibe was used in only a small minority of heart attack patients at hospital discharge in 2007-09, even in statin-intolerant individuals, despite being approved for lipid lowering in the United States since 2002.
This finding was based on a registry analysis led by William Wang, MS, a third year medical student at the DCRI who is mentored by Tracy Wang, MD, MHS, MSc, (pictured) and colleagues.
The study population included 13,738 heart attack patients aged 65 years or older discharged alive from 347 hospitals in the United States between July 2007 and December 2009. Of these patients, 74 percent were prescribed statin alone, 6 percent received a statin plus ezetimibe, 1 percent received ezetimibe alone, and 19 percent received neither.
The analysis also revealed that only 39 percent of patients discharged on statin and ezetimibe continued both to one year. Patients who had post-heart attack follow-up lipid testing were associated with lower persistence of ezetimibe use at one year.
The study results – linking Acute Coronary Treatment and Intervention Outcomes Network (ACTION) Registry-Get With the Guidelines (GWTG) data to Medicare part D prescription data for post-heart attack patients – were presented on Saturday at the annual Scientific Sessions of the American College of Cardiology in Chicago.
“The findings of our analysis were unexpected, with ezetimibe being used infrequently during 2007 to 2009 despite being an approved option available to patients who could not tolerate statin therapy,” said Tracy Wang, the senior author of the study. “In addition, ezetimibe was rarely added to statin therapy, even in patients with high LDL cholesterol levels who might have benefited from aggressive secondary prevention. This seems to reflect a lack of awareness of the potential utility of ezetimibe in this population.”
Ezetimibe, a non-statin agent, has been approved for lipid lowering in the United States since 2002, but the product’s benefit in terms of clinical outcomes when added to a statin in post-heart attack patients has only recently been demonstrated by the Improved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT). This found that the addition of ezetimibe to statin therapy significantly lowered both LDL cholesterol and the risk of cardiovascular events compared with statin monotherapy.
The current study offers baseline data for future evaluation of any changes in practice patterns based on the IMPROVE-IT findings.
Limitations of the study include the fact that Medicare data do not include LDL cholesterol values from post-discharge lipid tests, the study population was limited to patients aged 65 or above, the ACTION Registry-GWTG may not be representative of all U.S. hospitals, and causal inferences can not be drawn from an observational study.
Other DCRI authors included Anne S. Hellkamp, MS; Laine E. Thomas, PhD; Jacob Doll MD; and Eric D. Peterson MD, MPH.