Mediators linking obesity to childhood asthma.

Area of Science:

• Pediatric Health
• Respiratory Medicine
• Genetics

Background:

• Obesity and asthma share a strong association in children, yet the underlying causal mechanisms require elucidation.
• Key potential mediators include pulmonary function, airway inflammation, physical fitness, sleep-disordered breathing (SDB), and pubertal timing.

Purpose of the Study:

• To investigate the causal pathways linking childhood obesity to asthma.
• To quantify the mediating roles of pulmonary function, physical fitness, and early puberty in this association.

Main Methods:

• A Mendelian randomization (MR) study incorporating mediation analysis on data from 5965 children (Taiwan Children Health Study).
• Utilized MR two-stage least-squares and sensitivity analyses, complemented by prospective cohort analyses to establish temporal causality.

Main Results:

• Obesity-associated asthma risk is significantly mediated by impaired pulmonary function (61.63%), low physical fitness (73.76%), and early puberty (27.66%).
• Obesity negatively impacts lung function (FEV1/FVC) and physical fitness but is positively associated with early puberty.
• Conversely, improved lung function and physical fitness reduce asthma risk, while SDB and early puberty increase it.

Conclusions:

• Physical fitness and pulmonary function are critical mediators of obesity-induced asthma risk in children.
• Interventions aimed at enhancing physical fitness and lung function hold promise for reducing childhood asthma prevalence in obese populations.