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. The findings from a large, prospective cohort study point to genetic and pharmacogenetic differences as the basis for these racial disparities.

Based on prospective data from The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens (TENOR) study, Dr. Tmirah Haselkorn and colleagues used multivariate analysis with a sequential approach in an attempt to explain the differences between black and white adults with severe or difficult-to-treat asthma.

Their analysis included 1885 white patients and 243 black patients managed by more than 400 pulmonologists and allergists at 283 study sites across the US.

Blacks were more likely to have asthma classified as severe by their physicians and to be treated with three or more long-term controllers, Dr. Haselkorn, at Genentech Inc., in South San Francisco, California, and her associates report in the September issue of the Annals of Allergy, Asthma and Immunology.

However, they identified no differences in barriers to disease management between the two racial groups and no evidence of differences in asthma-related knowledge or behavior.

Moreover, the researchers add, “socioeconomic status, medication adherence, treatment setting, comorbidities, and allergy measures…do not explain the differences in asthma-related health outcomes between black and white patients.”

Thus, they conclude, the TENOR study data “support the emerging paradigm of a genetic and pharmacogenetic component of asthma in blacks.”

The investigators urge that their findings be used to develop more effective treatments and educational strategies for targeted interventions in blacks. “In addition, the examination of new therapies should be appropriately powered to examine the potential impact of race and ethnicity on efficacy.”

Reference:
Ann Allergy Asthma Immunol 2008;101:256-263.