Risk Factors and Age-Related Patterns of Asthma-Like Symptoms in Early Childhood

Abstract

Episodes of asthma-like symptoms in young children are common, but little is known about risk factors and their patterns for the daily symptom burden. We investigated a variety of possible risk factors and their age-related impact on the number of asthma-like episodes during age 0-3 years. The study population included 700 children from the COPSAC2010 mother-child cohort followed prospectively from birth. Asthma-like symptoms were recorded until age three by daily diaries. Risk factors were analyzed by quasi-Poisson regressions and interaction with age was explored. Diary data were available in 662 children. Male sex, maternal asthma, low birth weight, maternal antibiotic use, high asthma polygenic risk score, and high airway immune score associated with higher number of episodes in a multivariable analysis. Maternal asthma, preterm birth, caesarean section, low birth weight, and sibling(s) at birth showed increasing impact with age, whereas the siblings association decreased with age. The remaining risk factors had a stable pattern during age 0-3 years. For every additional clinical risk factor (male sex, low birth weight, maternal asthma) a child had, we found 34% more episodes (incidence rate ratio 1.34, 95% CI 1.21-1.48; p<0.001). Using unique day-to-day diary recordings, we identified risk factors for the burden of asthma-like symptoms in the first three years of life and describe their unique age-related patterns. This provides novel insight into the origin of asthma-like symptoms in early childhood which potentially pave a path for personalized prognostics and treatment.