Pathway From Central Obesity to Childhood Asthma: Physical Fitness and Sedentary Time Are Leading Factors.
Am J Respir Crit Care Med. 2014 Mar 26
Chen YC1, Tu YK, Huang KC, Chen PC, Chu DC, Lee YL.
Rationale: Available prospective studies of obesity and asthma have used only body mass index (BMI) as an indicator for adiposity; studies using detailed obesity measures are lacking, and the role of physical fitness level and sedentary time remains unexplored in the link between obesity and asthma.
Objectives: (1) Comparing various anthropometric measures of obesity in relation to childhood asthma, and (2) further characterising the interrelations amongst central obesity, physical fitness level, sedentary time, and asthma.
Methods: The nationwide Taiwan Children Health Study (TCHS) followed 2758 schoolchildren from fourth to sixth grade, annually collecting data regarding physical fitness, sedentary time, obesity measures (comprising body weight and height, abdominal/hip circumference, skin fold thickness, and body composition), asthma, and pulmonary function tests. The generalized estimating equation (GEE) was used for three years of repeated measurements to analyse the interrelation amongst obesity, sedentary time, physical fitness level, and asthma; a structural equation model (SEM) was used to explore the pathogenesis amongst these factors. Asthma incidence was analysed during a 2-year follow-up amongst centrally obese and non-obese groups in baseline non-asthmatic children.
Results: Central obesity most accurately predicts asthma. Low physical fitness levels and high screen time increase the risk of central obesity which leads to asthma development. Obesity-related reduction in pulmonary function is a possible mechanism in the pathway from central obesity to asthma.
Conclusions: Central obesity measurement should be incorporated in childhood asthma risk predictions. Children are encouraged to increase their physical fitness levels and reduce their sedentary time to prevent central-obesity-related asthma