Race a Factor in Angiography Referral

Patient race is a determining factor in receiving a referral for coronary angiography, according to a recent study from the Johns Hopkins Bloomberg School of Public Health, St. Agnes Healthcare, and Bon Secours Baltimore Health System. Once patients receive a referral, however, there is no significant difference in receiving the procedure when comparing white and black patients.

Coronary angiography is a very common invasive diagnostic procedure and precursor to life-saving open heart surgery. A small tube, called a catheter, is passed through a vein in the patient’s leg and into the blood vessels around the heart. After an image-enhancing substance is injected into the area, x-rays are taken to obtain images of the functioning of the heart’s blood vessels. The report, “Physician Referral Patterns and Race Differences in Receipt of Coronary Angiography,” was published in the August 2002 issue of the journal Health Services Research.

The study found that African-American patients were 71 percent as likely as white patients to obtain a referral for coronary angiography and 63 percent as likely to receive the procedure. White patients were more likely to be privately insured and less likely to have Medicare, Medicaid, or be uninsured. Analysis shows that patients who have private health insurance are more likely than uninsured patients to receive a referral.

Thomas A. LaVeist, PhD, a study co-author and associate professor of health policy and management at the Johns Hopkins Bloomberg School of Public Health, said, “We know from many previous studies that somewhere in the process of getting patients the heart surgery they need, African-American and white patients are ending up with different degrees of access. However, we don’t know exactly how or why that’s happening. It could be patient choice, doctor’s decision making, or something else. This study provides further evidence suggesting that patient preference is probably not what’s driving the race disparity in health care quality.”

The study was conducted using data from the Cardiac Access Longitudinal Study, an ongoing study of medical care access, utilization, and quality of life among white and African-American cardiac patients from three hospitals in Baltimore, Md. Two of the hospitals have a cardiac catheterization lab and the third refers patients to facilities to have the coronary angiography procedure done. Records for 7,929 patients were examined and, using the American College of Cardiology/American Heart Association criteria, classified into one of three classes for need of coronary angiography. Class 1 patients were those who received the procedure. Class 2 patients received the procedure frequently, but not consistently. Coronary angiography was not necessary for patients placed in class 3. Researchers supplemented the data found in the records with phone calls to patients.

Because it is not known why fewer African Americans are referred for the procedure, researchers question if these patients are signaling to physicians, in direct or indirect ways, that they would not be willing to submit to an invasive procedure such as coronary angiography, or if physicians may simply assume this fact without communication from the patient. Previous research shows that patients are unwilling to undergo procedures if they lack a familiarity with a particular treatment. Researchers also question whether some physicians hold a preconceived belief that African-American patients will not comply with suggestions for treatment, and thus, will not refer that patient.

“Once a referral is obtained, African-American patients are not less likely than white patients to follow through with the procedure. Thus, future research should seek to better understand the process by which the decision is made to refer or not refer patients,” said Dr. LaVeist.

Co-Authors of the study were Athol Morgan, MD, MHS, with One Heart, LLC, Melanie M. Arthur, PhD, with Oregon Health and Science University, Stephen Plantholt, MD, with St. Agnes Healthcare, and Michael Rubinstein, MD, with Bon Secours Baltimore Health Systems.

The study was funded by grants from the National Institutes of Health, the St. Agnes Foundation, and the Merck Company Foundation.