Individuals with asthma who are overweight may not respond as well to inhaled steroids as their leaner counterparts, a study hints. However, higher body weight or BMI does not appear to reduce response to a different type of asthma medication known as “leukotriene antagonists.”

Despite the findings, Dr. Marc Peters-Golden told Reuters Health: “I am not yet ready to suggest that our data should alter physicians’ prescribing patterns.”

Peters-Golden, of the University of Michigan Health System, Ann Arbor and colleagues examined data from four double-blind trials in which more than 3000 patients with moderate asthma were randomized to the leukotriene antagonist Singulair (montelukast), the inhaled steroid beclomethasone, or placebo.

The researchers classified the 32 percent of individuals with a BMI from 25 to 29.9 as being overweight and the 16 percent with a BMI of 30 and above as being obese.

The main end point involved days of asthma control. Other measures included lung function and rescue inhaler use.

The placebo response for all end points was generally reduced as BMI increased. This was also true of response to beclomethasone. However, the response to Singulair remained stable across BMI groups, investigators report in the European Respiratory Journal.

“If these data were reproduced in an appropriately designed prospective trial,” said Peters-Golden, “it could be an important clinical advance.”

Moreover, “our data may provide novel insight into the nature of obesity-associated inflammation… which could have bearing on other obesity-related inflammatory disorders, such as arthritis and atherosclerosis,” he concluded.

The study was funded by Merck, manufacturer of Singulair.

SOURCE: European Respiratory Journal March 2006.