Reasons Sought for Racial Disparities in Diabetes and Asthma Outcomes

September 24, 2007

ANN ARBOR, Mich. -- Differences in self-management and socioeconomic factors account only in part for the disparities in glycemic control and asthma outcomes between minority and white patients with diabetes and asthma, investigators in two studies found.

ANN ARBOR, Mich., Sept. 24 -- Differences in self-management and socioeconomic factors account only in part for the disparities in glycemic control and asthma outcomes between minority and white patients with diabetes and asthma, investigators in two studies found.

Minority and white diabetic patients differed significantly in medication adherence, which proved to be one of the strongest predictors of glycemic control, Michele Heisler, M.D., of the University of Michigan, and colleagues reported in the Sept. 24 issue of Archives of Internal Medicine.

However, differences in socioeconomic, clinical, access to care, and self-management factors still explained only 20% of the disparity in glycemic control, the researchers said.

"The major contributors to these large and recalcitrant disparities in glycemic control remain elusive," the authors concluded.

In a separate study published in the same issue of the journal, black patients with asthma had significantly worse clinical outcomes compared with whites, including more emergency room visits and hospitalizations, reported Sara E. Erickson, M.D., of the University of California, San Francisco, and colleagues.

In the diabetes study, Dr. Heisler and colleagues found that black and Latino adults had a 50% to 100% greater disease-related morbidity and mortality compared with whites.

Although disparities in the quality of care and access to care have often been blamed for minority diabetic patients' worse clinical outcomes, the researchers noted, those factors, combined with socioeconomic issues have failed to explain most of difference in outcomes.

Relatively little is known about racial differences in self-management and how those differences might influence clinical outcomes, so the researchers reviewed data from a national survey sample of 1,901 respondents ages 55 and older with diabetes mellitus. The respondents included 1,233 individuals who had valid at-home assessments of hemoglobin A1c.

Among 1,034 respondents taking antihyperglycemic medications, the average HbA1c was 8.07% in blacks and 8.14% in Latinos, which were significantly higher compared with the 7.22% average in whites (P