Lung function and overweight in school aged children after early childhood wheezing

Background and purpose: Recently, obesity has been connected with wheezing, asthma and reduced lung function. Most previous studies have been cross-sectional. The aim of the present follow-up study was to evaluate the association of preceding or current overweight or obesity with lung function at early and late school age after early childhood wheezing.

Material and methods: From the 100 children hospitalized for infection associated wheezing at <24 months of age, 83 attended the control visit at 4.0 years, 82 at 7.2 years and 81 at 12.3 years of age. Flow-volume spirometry was performed in 79 children at 7.2 years and in 80 children at 12.3 years of age. The weight status was assessed by calculating body mass index (BMI) at all visits. Age- and gender-specific BMI standard deviation scores (BMI-SDS) of >1.3 SD and >2.0 SD were defined to mean overweight and obesity, respectively.

Results: Overweight at both 7.2 and 12.3 years of age was associated with decreased FEV1 /FVC (forced expiratory volume in 1 sec/forced vital capacity). Overweight and obesity at 7.2 years of age were associated with decreased FEV1 /FVC and MEF50 (maximal expiratory flow at 50% of FVC) at 12.3 years of age. The results were similar by continuous and categorized analyses, being robust to adjustments for viral findings during early childhood wheezing and asthma maintenance medication at school age.

Conclusion: Overweight and obesity are significant risk factors for reduced lung function at school age after early childhood wheezing. Thus, early-life wheezers should avoid excessive weight gain during childhood.