Obese Have Poorer Asthma Control

Canadian researchers suggest obese people with asthma may carry a specific trait or phenotype that causes them to have poorer asthma control.

Quebec researchers compared pulmonary function changes, methacholine challenge scores, sputum induction cell counts, symptom perceptions, body mass index /waist circumference, and waist-to-hip ratio of 44 obese subjects with asthma with 44 non-obese subjects with asthma.

Those who were obese had poorer asthma control, as well as lower total lung capacity, expiratory reserve volume, functional residual capacity and residual volume. Blood serum C-reactive protein and fibrinogen levels also were higher in obese subjects than non-obese subjects.

The study, published in the journal Chest, said the bronchial and systemic inflammatory characteristics and patterns of pulmonary function changes suggest that obese patients may have a different phenotype of asthma. Phenotypes result from the expression of an organism’s genes as well as the influence of environmental factors and possible interactions between the two.