Related Experiment Videos
Body mass index and phenotype in subjects with mild-to-moderate persistent asthma
E Rand Sutherland1, Erik B Lehman, Mihaela Teodorescu
1National Jewish Health, Denver, CO 80206, USA. sutherlande@njhealth.org
Background:
Although obesity has been hypothesized to worsen asthma, data from studies of subjects with well-characterized asthma are lacking.
Objective:
We sought to evaluate the relationship between body mass index (BMI), asthma impairment, and response to therapy.
Methods:
BMI (in kilograms per meter squared) and asthma phenotypic and treatment response data were extracted from Asthma Clinical Research Network studies. The cross-sectional relationship between BMI and asthma impairment was analyzed, as was the longitudinal relationship between BMI and response to asthma controller therapies.
Results:
One thousand two hundred sixty-five subjects with mild-to-moderate persistent asthma were evaluated. Analyses of lean versus overweight/obese asthmatic subjects demonstrated small differences in FEV1 (3.05 vs 2.91 L, P = .001), FEV1/forced vital capacity ratio (mean, 83.5% vs 82.4%; P = .01), rescue albuterol use (1.1 vs 1.2 puffs per day, P = .03), and asthma-related quality of life (5.77 vs 5.59, P = .0004). Overweight/obese asthmatic subjects demonstrated a smaller improvement in exhaled nitric oxide levels with inhaled corticosteroid (ICS) treatment than did lean asthmatic subjects (3.6 vs 6.5 ppb, P = .04). With ICS/long-acting beta-agonist treatment, overweight/obese asthmatic subjects demonstrated smaller improvements in lung function than lean asthmatic subjects, with an 80 mL (P = .04) and 1.7% (P = .02) lesser improvement in FEV1 and FEV1/forced vital capacity ratio, respectively. Significant differences in therapeutic response to leukotriene modifiers between BMI categories were not observed.
Conclusions:
Increased BMI is not associated with clinically significant worsening of impairment in subjects with mild-to-moderate persistent asthma. There is a modest association between increased BMI and reduced therapeutic effect of ICS-containing regimens in this patient population. Prospective studies evaluating the effect of being overweight or obese on treatment response in asthma are warranted.
Related Concept Videos
Asthma III: Clinical Manifestations
Asthma I: Introduction
Asthma-III: Symptoms and Complications
Classification of Asthma
Asthma-II: Pathophysiology and Classification
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features
Asthma: Pathogenesis and Management
Asthma is classified as allergic and non-allergic. Allergens such as dust mites, pollen, and pet dander trigger allergic asthma, while factors like cold air, intense emotions, or exercise can induce non-allergic asthma.