Peripheral Airway Impairment and Dysanapsis Define Risk of Uncontrolled Asthma in Obese Asthmatic Children

• Published in: The journal of allergy and clinical immunology in practice (Cambridge, MA) Vol. 10; no. 3; p. 759
• Main Authors: Jung, Yela, Jean, Tiffany, Morphew, Tricia, Galant, Stanley P
• Format: Journal Article
• Language: English
• Published: United States 01.03.2022
• Subjects: Asthma - epidemiology; Body Mass Index; Child; Female; Humans; Male; Overweight; Pediatric Obesity; Vital Capacity; Reactance; Resistance; Obesity; Peripheral airway impairment; Children; Dysanapsis; Impulse oscillometry; Uncontrolled asthma
• ISSN: 2213-2201
• DOI: 10.1016/j.jaip.2021.09.029

Factors that determine the relationship between obesity and poor outcomes in asthmatic children are not well understood. Dysanapsis and peripheral airway impairment (PAI) could provide an explanation in the obese asthmatic patient. To determine the effect of obesity on increased dysanapsis and PAI and establish the effect of obesity, dysanapsis, and PAI on increased risk of uncontrolled asthma. We evaluated 206 children with moderate to severe asthma, aged 4-18 years, to determine the relationship of body mass index (BMI) to increased dysanapsis and PAI, using reference values. We examined the probability of obesity, dysanapsis, and PAI increasing the risk of uncontrolled asthma by BMI categorically and BMI z scores using generalized linear model analyses. Compared with normal-weight children, overweight and obese children had increased forced vital capacity % predicted and obesity increased odds of dysanapsis by 2.32 (P = .04), while PAI showed an age-dependent effect, with increased odds of 2.09 for children younger than 12 years (P = .08) and 54.14 for those 12 years and older (P = .003). For each unit increase in BMI z score, there was an increased odds ratio of 1.57 for dysanapsis (P = .009), greater in males, OR of 3.10, P = .009, and of 1.39 for PAI for those younger than 12 years (P = .042) and of 4.60 for those 12 years and older (P = .002). Obesity's relationship to uncontrolled asthma was indirect, as not significant when adjusted for the direct effect of dysanapsis and PAI, which were highly significant predictors, with increased odds of 28.01 for dysanapsis for those younger than 12 years (P < .001) and of 3.09 for PAI (P = .005). Overweight and obesity significantly increase odds of dysanapsis and PAI, in an age and gender-specific manner, increasing the probability of uncontrolled asthma.