Researchers identify risk factors for uncontrolled asthma among children with obesity

Children with overweight or obesity faced significantly higher odds for dysanapsis and peripheral airway impairment, according to a presentation at the American College of Allergy, Asthma & Immunology Annual Scientific Meeting.

The retrospective, population-based study also found that these odds greatly enhanced the probability for uncontrolled asthma in this population.

“Factors that determine the relationship between obesity and poor outcomes in asthmatic children are not well understood,” Yela Jung, MD, a PGY3 internal medicine resident in the department of medicine at University of California Irvine, said during the presentation, adding that dysanapsis and peripheral airway impairment (PAI) could provide an explanation.

The researchers aimed to identify a relationship between categorical and continuous BMI z scores with dysanapsis, PAI, age and sex, as well as how those factors affected uncontrolled asthma.

The study included 206 children and adolescents aged 4 to 18 years with moderate to severe asthma. The researchers examined the probability of obesity, dysanapsis and PAI increasing the risk for uncontrolled asthma by BMI categorically and BMI z scores using generalized linear model analyses.

Compared with children of normal weight, children with obesity were more likely to develop dysanapsis (OR = 2.32; P = .04). Also, PAI had an age-dependent effect, with increased odds for children aged 12 years and older (OR = 54.14; P = .003).

For each unit increase in BMI z score the researchers found increased likelihood of dysanapsis (OR = 1.57; P = .009), especially among males (OR = 3.01; P = .009), and increased PAI among children aged 12 years and older (OR = 4.6; P = .002) and younger than 12 years (OR = 1.39; P = .042).

“BMI z scores did not significantly impact the risk for uncontrolled asthma after adjustment for dysanapsis and PAI,” Jung said.

Patients aged younger than 12 years with dysanapsis had a significantly increased risk for severe asthma (OR = 28.01; P < .001). Patients with PAI had a greater risk for uncontrolled asthma regardless of age (OR = 3.09; P = .005).

When PAI and dysanapsis were not considered, 30.1% of patients had uncontrolled asthma. When PAI was added to dysanapsis, however, the percentage of patients with uncontrolled asthma increased from 50% to 81.5%.

“Therefore, our conclusion is overweight and obesity significantly increase odds of dysanapsis and PAI in an age-specific matter, greatly enhancing the probability of uncontrolled asthma,” said Jung.