Ethnicity Influences Diabetes Damage, Study Finds
The link between ethnicity and complications from diabetes is more consistent than researchers had previously thought, even when all patients have equal access to health care, a large-scale study has found.
Kaiser Permanente researchers studied more than 62,000 diabetes patients in California and found that whites were more likely than blacks, Asians and Latinos to experience heart attacks but less likely to suffer kidney failure.
Researchers say the study provides the first definitive data about disparities in how diabetes affects different ethnic groups.
“When people do have fairly consistent access to health care, ethnic disparities diminish or are dramatically different” than previously reported, said Andrew Karter, an epidemiologist with Kaiser Permanente in Oakland.
The differences probably have a genetic link, said Karter, the lead author of the study, which is to be published today in the Journal of the American Medical Assn.
Karter said most research comparing the incidence of disease among different ethnic groups includes insured and uninsured patients, sometimes leading to inconclusive results.
“You may get a biased look at complications in these national studies,” he said, adding that if a disparity exists, “you can’t really tell if that’s due to biology or quality of care.”
The study compared the rates of incidence of major complications among the HMO’s patients with Type 1 and Type 2 diabetes from 1996 to 1999. Type 1 patients require insulin treatments to control the disease, while those with Type 2 often can combat symptoms through diet and exercise.
In addition to the finding about heart attacks, researchers found that whites and blacks were at equally greater risk of developing stroke or congestive heart failure than were Asians and Latinos, Karter said. Asians were least likely to require amputations.
But blacks, Latinos and Asians were far more likely than whites to experience kidney failure. The mortality rate is 50% in the first five years of kidney disease, Karter said.
Researchers described the paper as important and say it opens up questions for study.
“We have to look at the disparity and not assume whites are going to do better,” said Dr. Richard Hamman, chief of preventive medicine at the University of Colorado School of Medicine.
He warned, however, that minorities develop Type 2 diabetes at a higher rate than do white patients. A larger number of members of ethnic groups are at risk overall as a result.
For different ethnic groups, this confirms that “there are certain intrinsic differences,” said Dr. Mayer B. Davidson, diabetes researcher and director of the clinical trial unit at Charles R. Drew University of Medicine and Science.
