Life course body mass index through childhood and young adulthood and risks of asthma and pulmonary function impairment

Abstract

Background Adiposity is a key risk factor for asthma and impaired pulmonary function. Objectives We aimed to identify the critical period of life course adiposity for asthma in childhood and young adulthood, and to determine whether associations of adiposity and asthma vary across ages. Methods Birth weight and body mass index (BMI) from birth to 17 years of age were assessed in 6130 children from the Taiwan Children Health Study. Logistic regression for asthma outcome and linear regression for pulmonary function outcome were used to investigate associations of adiposity with asthma. Seventeen BMI‐related single‐nucleotide polymorphisms were used to obtain genetic instrumental variables for adiposity to perform Mendelian randomization (MR) analysis. Results Using both regression model and MR analyses, we confirmed that the critical period of adiposity in predicting childhood asthma would be before age 6 years. Further, we discovered that the sensitive period of adiposity gain related to young adulthood asthma was the prepubertal stage. Risks of asthma at age 17 per unit increase in z‐score of the BMI increased from 0.94 (95% CI: 0.79–1.11) at birth, and became greater than 1.00 between age 11 and 12, then increased to 1.08 (95% CI: 0.95–1.22) at age 17. The associations of life course BMI with asthma and pulmonary function impairment at age 12 and with asthma at age 17 increased with age. The aforementioned association was most prominent among central obesity indicators. Conclusions To prevent asthma in childhood and young adulthood, we should aim at promoting healthy growth at the toddler period and prepubertal stage.

Risk factors of asthma in the Asian population: a systematic review and meta-analysis

“…Multiple pre- and perinatal factors were also frequently studied as a risk factor contributing to asthma, including breastfeeding (26 studies) [ 27 , 36 , 40 , 44 , 64 , 65 , 69 , 70 , 77 , 85 , 86 , 89 , 111 , 122 , 126 , 127 , 131 , 133 , 135 , 138 , 153 , 199 , 243 – 246 ], birth weight (17 studies) [ 66 , 69 , 84 , 85 , 87 , 126 , 127 , 130 , 132 , 133 , 183 , 199 , 228 , 247 , 248 ], gestational age (11 studies) [ 36 , 69 , 77 , 84 , 85 , 126 , 133 , 140 , 233 , 247 , 248 ], and the method of childbirth (10 studies) [ 36 , 47 , 64 , 84 , 126 , 131 , 133 , 249 – 251 ]. Given most studies were heterogeneous on their assessment approaches and analytical methods for these risk factors, meta-analyses were only performed for exclusive breastfeeding, low birth weight (< 2500 g), preterm birth (≤ 37 weeks), and childbirth by caesarean section (reference category: natural birth).…”

Can birth weight predict offspring’s lung function in adult age? Evidence from two Swedish birth cohorts

“…Body mass index and adiposity growth during childhood for predicting young adult asthma has been studied previously [ 53 ]. The mis-match concept was first developed to address increased cardiometabolic risk in babies born small and achieving a high childhood or adult BMI [ 54 , 55 ], but also according to changes in kidney function [ 56 ] and the increased risk of respiratory disease [ 51 ], most notably a decrease of FEV in mis-match young babies at age 4–15 weeks [ 57 ].…”

Causal risk factors for asthma in Mendelian randomization studies: A systematic review and meta‐analysis

“…Another study from Chen et al. (quality score 7) showed no causal effect of higher BMI from birth to 17 years on the risk of asthma at age 17 26 …”

“…17,23 Another study from Chen et al (quality score 7) showed no causal effect of higher BMI from birth to 17 years on the risk of asthma at age 17. 26 Zeng et al 27 (quality score 12, certainty of evidence graded high) investigated birth weight, as it is often used as a proxy for early life development and potentially an effect on adult diseases as well; however, Zeng et al found no causal association between adult asthma and birth weight.…”