WASHINGTON — African American patients with dyslipidemia are less likely than non-Hispanic whites to achieve LDL cholesterol treatment goals, Luther T. Clark, M.D., and his associates reported in a poster at a conference on cardiovascular disease epidemiology and prevention sponsored by the American Heart Association.
In a national survey of physician compliance with guidelines that were issued in the third report of the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP III), African American ethnicity remained a strong predictor of lower success in reaching low-density lipoprotein (LDL) cholesterol goals, even after adjustment for cardiovascular disease risk factors, said Dr. Clark, chief of cardiovascular medicine at the State University of New York Downstate Medical Center, Brooklyn.
In the study, supported by AstraZeneca PLC, a total of 376 U.S. physicians who were high prescribers of lipid-modifying medications each enrolled 10 or 20 consecutive dyslipidemic patients.
Data associated with a single office visit were entered into special software on a personal digital assistant device and then uploaded to a central database via the Internet.
The 4,885 patients studied were aged 20–75 years and had been on diet and/or a stable dose of drug therapy for at least 3 months. Most patients (80%) were non-Hispanic whites, 8% were African American or black, 4% were Hispanic, and 3% were Asian.
Physician specialties included family practice (40%), general internal medicine (40%), cardiology (15%), and endocrinology (2%). Most physicians were male (90%), board certified (90%), and office based (99%).
Achievement of NCEP ATP III treatment goals for LDL cholesterol level was significantly lower overall among African Americans than in non-Hispanic whites (54% vs. 69%).
This was true in all risk categories—those with fewer than two cardiovascular risk factors (82% vs. 90%), those with two or more risk factors (59% vs. 77%), and those at highest risk by virtue of having either coronary heart disease (CHD) or a CHD risk equivalent (44% vs. 58%), Dr. Clark and his associates wrote.
The disparity in LDL goal achievement remained, even after adjustment for age, gender, smoking status, family history of CHD, hypertension, HDL cholesterol category, type of therapy (diet vs. drug), hypertriglyceridemia, obesity, and physician specialty.
After the full adjustment, African Americans were less than half as likely (odds ratio 0.48) to have reached their LDL cholesterol goals, they said.
“These findings are disappointing, but not surprising. [They] are consistent with those from other surveys that have shown that CHD risk factors are less well controlled in African Americans,” Dr. Clark told this newspaper in a follow-up interview.
Although the reasons are not clear, the fact that the difference persisted after adjustment for both physician specialty and receipt of statins suggests that patient behavior is at least a contributing factor. But physiologic variation may be at work as well.
“Surprisingly little data have been published directly comparing lipid responses to available treatments in African American and non-Hispanic white patients. Therefore, it is also possible that physiologic factors could have played a role in the lower frequency of goal achievement in African Americans,” Dr. Clark commented.