Impact of obesity on the severity and therapeutic responsiveness of acute episodes of asthma.

BACKGROUND: It has been suggested that obesity adversely influences both the severity and the therapeutic responsiveness of chronic asthma. However, it is unclear if it also impacts acute situations. METHODS: To determine whether adiposity worsens the clinical and physiological manifestations of acute asthma and limits therapeutic effectiveness of standard treatment, we contrasted signs, symptoms, medication use, arterial oxygen saturation, peak expiratory flow rate, and the bronchodilator response to standard doses of albuterol in 90 non-obese and 90 obese asthmatics as they presented for urgent care. Treatment and clinical decisions were systematized using published care paths and the peak flow was measured with standard techniques. Body mass index (BMI) was calculated according to consensus criteria. RESULTS: Other than BMI (p < .001), there were no between-group differences in age, gender, race, signs, symptoms, pulse oximetry, or pre-presentation medication use. The pretreatment peak flow in the obese population was 22.4% higher on average (p = .007), but there were no differences in the distribution of severity (p = .38), the response to albuterol (p = .61), or admission-discharge ratios (p = .62). CONCLUSIONS: Obesity does not adversely influence the severity or the resolution of acute episodes of asthma.