Patients with cardiovascular disease or cardiovascular risk factors who adhere with high-intensity statin and/or ezetimibe therapy have a lower risk for cardiovascular events vs patients who do not adhere with low-intensity therapy. This is according to findings from a retrospective cohort study published in JAMA Network Open.
Data from the Clinical Practice Research Datalink collected from January 2010 through February 2016 were analyzed retrospectively. Data from patients with documented cardiovascular disease, type 2 diabetes without cardiovascular disease or chronic kidney disease (CKD), or CKD without cardiovascular disease who received primary care in the United Kingdom were included in the analysis. All patients had recently initiated treatment with a first statin and/or ezetimibe prescription up to December 31, 2013, and were given another prescription for either or both medications the following year.
The study investigators assessed annual adherence rates using the percentage of days covered, with a covered rate of ≥80% classified as treatment adherent.
Additionally, treatment adherence was determined by the expected percentage reduction of low-density lipoprotein cholesterol level: low (<30% reduction), moderate (30% to <50% reduction), or high (≥50% reduction). The primary outcome included a composite of cardiovascular death or hospitalization for heart failure, unstable angina, myocardial infarction, ischemic stroke, or revascularization.
A total of 29,797 newly treated patients with cardiovascular disease (n = 16,701), type 2 diabetes without cardiovascular disease or CKD (n = 12,422), and CKD without cardiovascular disease (n = 674) were included.
Among patients with cardiovascular disease, high-intensity therapy was associated with a greater likelihood of adherence in year 1 and year 6 (84.1% and 72.3%, respectively) vs low-intensity therapy (57.4% vs 48.4%, respectively).
Each 10% increase in both adherence and treatment intensity was associated with a 10% lower risk for cardiovascular disease outcomes (hazard ratio, 0.90; 95% CI, 0.86-0.94). In addition, patients who were adherent with a high-intensity lipid-lowering regimen had a lower risk compared with patients untreated for ≥1 year (hazard ratio, 0.60; 95% CI, 0.54-0.68).
Limitations of the study include the lack of data on patients’ lifestyle factors as well as the lack of data on adherence with other cardiovascular medications.
“Strategies that optimize [low-density lipoprotein cholesterol] reduction through better use of high-intensity statins and improved adherence could potentially reduce the risk of [cardiovascular disease] in high-risk populations,” the investigators concluded.
Khunti K, Danese MD, Kutikova L, et al. Association of a combined measure of adherence and treatment intensity with cardiovascular outcomes in patients with atherosclerosis or other cardiovascular risk factors treated with statins and/or ezetimibe. JAMA Netw Open. 2018;1(8):e185554.