Clinical and economic impact of statin therapy compliance on hyperlipidemic patients with concomitant CHD risk factors

Abstract

In cholesterol management, a common and widely used class of drug is 3-hydroxyl-3-methylglutaryl coenzyme A reductase inhibitor (statin). These drugs lower cholesterol by slowing down the production of cholesterol and by increasing the liver's ability to remove LDL cholesterol already in the blood. Statins are well tolerated, and serious side effects such as liver problems, muscle soreness, pain, and weakness are rare. Compliance to prescribed medication is an important component of appropriate pharmacotherapy. Maryland Medicaid managed care (MCO) data were used to examine risk factors of patient non-compliance to statin therapy and its impact on healthcare utilization and the risk of having a new cardiovascular event among patients with hyperlipidemia and one or more CHD risk factors. The sample included Maryland Medicaid MCO patients who were diagnosed with hyperlipidemia and an additional CHD risk factor and were statin drug users. The proportion of patients compliant to statin therapy was 38 percent. The average age of the sample was 50. Over half of the sample was African American (50.69 percent), the rest Caucasian (41.54 percent) and Others (7.77 percent). Results for predictors of statin therapy compliance indicated that age and race had a significant impact on compliance. Although statistically non-significant, compliance was higher among patients with higher Charlson Comorbidity Index (CCI) scores. The probability of being compliant to statin therapy increased with age. African Americans (odds ratio = 0.662, 95 percent CI = 0.580-0.756) and Other race (odds ratio = 0.689, 95 percent CI = 0.549-0.865) groups were less compliant to statin therapy than Caucasians. The cost model indicated that compliant patients did not differ in cardiovascular disease (CVD) related medical costs from semi-compliant or non-compliant patients. The results of the CV risk model indicated that patients who were compliant to statin therapy had lower risk of a cardiovascular event than patients not compliant to statins and the findings were statistically significant. In conclusion, the study did not find significant evidence to prove that compliant patients would have lower CVD related costs. Risk of CV event was lower in compliant patients and was statistically significant. The study was conducted from January 1, 2002 through June 31, 2005. Future studies could examine the impact of compliance over a longer period of time in the Medicaid population.