NEW YORK (Reuters Health) - Asthma patients who are black tend to have more severe disease than asthma patients who are white, leading to more asthma control problems, higher rates of emergency department visits, and overall worse quality of life. These findings point to genetic differences that lead to poor responses to drug therapy as the source of these racial disparities.
Based data obtained from The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens (TENOR) study, Dr. Tmirah Haselkorn and colleagues undertook an in-depth analysis in an attempt to explain the differences between black and white adults with severe or difficult-to-treat asthma.
Their analysis included 1,885 white patients and 243 black patients who were treated by more than 400 specialists in lung diseases and allergies at 283 study sites across the United States.
Blacks were more likely to have asthma that was classified as severe by their physicians and to be treated with three or more long-term controller drugs, Haselkorn, of Genentech Inc., in South San Francisco, California, and her associates report in the Annals of Allergy, Asthma and Immunology.
However, the researchers found no differences in access to treatment between the two racial groups and no evidence of differences in asthma-related knowledge or behavior in the patients.
Socioeconomic status, adherence to drug therapy, treatment setting, the presence of other diseases and various allergy measures also did not explain the differences in asthma-related illness and severity between the two races.
The researchers conclude that the TENOR study data support the idea of a genetic component that causes a poor response to asthma treatment in blacks.
The investigators urge that these findings be used to develop more effective asthma treatments and educational strategies for black patients who are having problems controlling their disease. In addition, future clinical trials evaluating new therapies should be designed to also examine the potential impact of race and ethnicity on treatment response.
SOURCE: Annals of Allergy, Asthma and Immunology, September 2008.