2006 OPEN FORUM Abstracts
THE RELATIONSHIP OF INCREASED BMI ON QUALITY OF LIFE, ASTHMA SEVERITY AND SPIROMETRY IN ASTHMATIC PATIENTS ENROLLED IN A DISEASE MANAGEMENT PROGRAM
Ditsch, KA, BS, RRT, Peters, JI,
MD, MHS, RRT, Inscore, S, MD, Smith, P,
PhD, Fallot, A, MD, Ellis, R, MD, Galbreath, AD, MD; University
of Texas Health Sciences Center at San Antonio, TX
Background: Asthma and obesity are chronic conditions that affect more than 60 million people in the United States. The purpose of this study was to assess the impact of obesity on spirometric values in asthmatic patients and to assess the impact on severity of asthma as well as quality of life (QOL).
Methods: A single-center, randomized, controlled clinical trial of disease management in asthma was conducted from 2003-2006 by The University of Texas Health Science Center at San Antonio and several partner institutions. Enrollment consisted of 902 patients: 473 pediatric (ages 5-17) and 429 adults (18- 65). Over half of adult patients (n=250) met the criteria of obesity, (BMI 30 kg/m2 or greater) and over one-quarter of children (n=132) had a weight greater than the 95th percentile for age, height and gender. The impact of categorized body mass index (BMI), <30, 30-40, and >40 kg/m2, on pulmonary function tests and quality of life (assessed by SF 36 and Pediatric Asthma Quality of Life Questionnaire) was assessed with analysis of variance. The significance of the association between healthcare utilization, asthma severity and categorized BMI was assessed with Pearson's chi-square statistic. All statistical testing was two-sided with a significance level set at p< 0.05. All analyses were carried out with SAS version 9.1 for Windows (SAS Institute, Cary, NC).
Results: Adult obese patients had a significantly higher FEF25-75 (p= 0.027) and a significantly lower % predicted FVC (p=0.009) than adult asthmatics with a BMI < 30 kg/m2. A greater percentage of adult obese asthmatics had an FEV1/FVC > 75%, (p=0.015) when compared to adult asthmatics with a BMI of < 30kg/m2. There was a significant difference in quality of life scores for obese adults (p= 0.007), but obesity did not appear to be related to quality of life scores for children (p=0.17). There was a trend toward significance for adult obese asthmatics hospitalized for asthma (p=0.064). Asthma severity classification was not significantly different among the three obesity categories for adults (p=0.46); however, a greater percentage of obese children were classified as having severe persistent asthma and the difference was significant (p=0.019).
Conclusions: For this sample population, obesity in children did not seem to impact spirometry measurements or quality of life scores, but did have an impact on disease severity classification. In adults, obesity had a negative impact on quality of life scores. Spirometry measurements that seemed influenced by obesity in adults suggested a volume limitation as opposed to an airflow limitation. Healthcare utilization, more specifically, inpatient admissions for asthma may be positively correlated with obese adults. Further analysis of these data will help identify markers that may indicate future morbidity for obese asthmatics and to assess how relationships may vary across demographic subgroups.