Racial disparities in treatment for dyslipidemia in patients with diabetes

Patients diagnosed with diabetes (DM) are at a higher risk for cardiovascular disease events and mortality than patients without diabetes. To reduce this risk, strict management of hypercholesterolemia in patients with DM is recommended. The purpose of this study was to evaluate whether treatment plan (i.e. lipid testing, treatment, goal attainment) for dyslipidemia differed over time between African American and white patients with DM in an equal access environment.

A retrospective cohort of 11,411 managed care enrollees were followed from baseline (1997-1998) until the first of death, health plan disenrollment, or end of study period (2007). Automated health plan data were used to gather patient sociodemographic characteristics. Medical claims data including frequency of physician visits, as well as laboratory tests and clinical results, were collected. Prescription drug claims data were used to compile medication dispensing and adherence information. Rates of testing, treatment, and low-density lipoprotein-cholesterol (LDL-C) goal attainment stratified by race were estimated and compared by chi square tests for each follow-up year (1999-2007). Multivariable logistic regression models that accounted for repeated events, controlling for baseline factors, were used to estimate racial effects on dependent variables.

After adjusting for sociodemographic and cardiovascular risk variables, year of follow-up, number of visits, co-payments for visits and prescriptions, and LDL-C levels at baseline, African American patients were 28 % less likely to be prescribed lipid-lowering agents (OR: 0.72, 95% CI: 0.65 – 0.80) when compared with white patients. Moreover, African Americans were 35% less likely than whites to have their medication dosage altered (OR: 0.65, 95% CI: 0.59 – 0.73). African Americans were also 26% less likely to be at their treatment goal (LDL-C <100 mg/dL) than their white counterparts (OR: 0.74, 95% CI: 0.67-0.82).

This study supports the finding of others in that LDL-C management indicators consistently demonstrated a racial disparity between African American and white patients. Relative to white patients, African Americans were less likely to be tested, treated or to achieve LDL-C goal. Additionally, all patients observed had health insurance coverage and hence financial access to care, suggesting that other factors contributed to the observed racial disparity. Differences in physician testing and prescribing practices, patient ability to pay for prescriptions and visit co-pays, and differences in medication adherence by race may all play a role in the disparities detected.