High-intensity statin prescriptions often unfilled after CHD events

National guidelines recommend high-intensity statin therapy after a CHD-related hospitalization, but most Medicare beneficiaries hospitalized for CHD events did not fill prescriptions for high-intensity statins after discharge, according to the results of a retrospective cohort study.

It is not known to what extent the failure to fill was due to patients receiving prescriptions for high-intensity statins but not filling them, or from them never receiving prescriptions for high-intensity statins.

The study included a 5% random sample of Medicare beneficiaries aged 65 to 74 years who filled a statin prescription after a CHD event (n=8,762), defined as MI or coronary revascularization, in 2007, 2008 or 2009.

The researchers defined high-intensity statins as atorvastatin (Lipitor, Pfizer) 40 mg to 80 mg, rosuvastatin (Crestor, AstraZeneca) 20 mg to 40 mg, or simvastatin 80 mg.

Rate varied by pre-hospital status

Robert S. Rosenson, MD, and colleagues found that 27% of the first statin prescription fills after discharge for a CHD event were for a high-intensity statin. Among beneficiaries not taking a statin before hospitalization, the rate was 23.1%; for those taking low- or moderate-intensity statins before hospitalization, it was 9.4%; and for those taking high-intensity statins before hospitalization, the rate was 80.7%.

Compared with beneficiaries not on statins before hospitalization, the adjusted RR for filling a high-intensity statin was 4.01 (95% CI, 3.58-4.49) among those taking high-intensity statins before hospitalization and 0.45 (95% CI, 0.4-0.52) for those taking low- or moderate-intensity statins before hospitalization, according to the researchers.

Within 365 days of discharge, 11.5% of beneficiaries whose first post-discharge fill was for a low- or moderate-intensity statin had filled a prescription for a high-intensity statin, Rosenson, from the Icahn School of Medicine at Mount Sinai, and colleagues found. The overall rate of high-intensity statin prescription fills within 365 days of discharge was 35%.

Patients with acute MI were more likely to receive high-intensity statin therapy than those who underwent CABG or PCI for a reason other than acute MI, according to the researchers.

Explanations offered

The researchers wrote that the Medicare claims data do not enable an evaluation of what factors might account for the finding, but offered several possible explanations, including:

Patients may have been at or near their LDL goals before their hospitalization.
Cost may have played a role, as atorvastatin was not available in generic form during the years included in the study.
Drug-drug interactions, or the potential for them, may have prevented filling of high-intensity statin prescriptions.
Some patients may have been intolerant to higher statin doses.
Some patients may have had conditions, such as renal insufficiency or hepatic disease, for which high-intensity statin use is contraindicated.
Confusion resulting from post-hospital transitions in care may have prevented some patients from receiving high-intensity statins after discharge.

Prakash Deedwania

In a related editorial, Prakash Deedwania, MD, wrote that “the available data are quite concerning regarding the significant gap in the guideline-recommended use of high-intensity statins in these high-risk patients.” He wrote that it is unlikely that a patient would ignore a physician’s advice after a significant cardiac event, so more plausible explanations include physician unawareness of or disagreement with the guidelines, physician belief that high-intensity statins are not needed if the patient’s LDL is already low, physician concern about adverse events related to high-intensity statins and inadequate discharge planning.

“On the patient side, this lag could reflect real or perceived medication cost issues, polypharmacy (especially in the elderly), noncompliance and nonadherence,” Deedwania, from the University of California, San Francisco School of Medicine, wrote. “The recommendations of the guidelines in terms of using a cardiac team approach should help alleviate many of these issues.”

For more information:

Deedwania P. J Am Coll Cardiol. 2015;doi:10.1016/j.jacc.2014.10.049.

Rosenson RS. J Am Coll Cardiol. 2015;doi:10.1016/j.jacc.2014.09.088.

Disclosure: The study was sponsored in part by a grant from Amgen. Rosenson reports various financial ties with Aegerion, Amgen, AstraZeneca, Eli Lilly, F. Hoffmann-La Roche, GlaxoSmithKline, LipoScience, Novartis, Regeneron, Sanofi, Teva and The Medicines Company. Deedwania reports no relevant financial disclosures.