Asthma, a chronic respiratory condition, often begins in childhood and can persist into adulthood. In Canada, it’s the most prevalent chronic disease among children, affecting one in eight.
While many preschoolers with asthma become asymptomatic by age 6, a significant portion still suffer from impaired lung function later in life. Poor asthma control during childhood has been linked to respiratory problems in adulthood. Hence, understanding the potential cause of early childhood asthma could help mitigate the condition.
Asthma arises from a complex interplay between genetic predisposition and environmental factors, particularly during the perinatal period and the first few years of life. However, most studies have focused on asthma development and prevalence, neglecting to explore the determinants of asthma control. Addressing this gap, a recent study by Dr. Linn Moore, an Adjunct Professor at the University of Alberta, aimed to evaluate the associations between maternal, perinatal, and early-life factors and asthma control in newly diagnosed preschool children.
The study, published in the British Medical Journal, examined data from children born in Alberta who were diagnosed with asthma before age 5. Maternal health data were collected two years before pregnancy, and follow-up data on the children were collected two years after the initial asthma diagnosis.
The primary outcome was asthma control during preschool years, which was categorized as controlled, partly controlled, or uncontrolled asthma. Maternal factors such as age at delivery and history of asthma, along with perinatal and early-life factors, were analyzed.
Among the 7,206 children studied, more than half had controlled asthma, while around one-third had partly controlled asthma, and nearly 12% had uncontrolled asthma within two years of diagnosis. Notably, a higher proportion of boys had asthma compared to girls, and the mean age at diagnosis was 2.6 years.
Maternal factors played a significant role. Children born to mothers with atopic disease were less likely to have partly controlled asthma. Perinatal factors such as antibiotic use, gestational diabetes, smoking during pregnancy, C-section birth, and summer birth, as well as early-life hospitalizations for respiratory illness, increased the risk of partly or uncontrolled asthma in preschoolers.
The present study identified potential factors influencing poor asthma control in early childhood and beyond. All in all, the results suggest that efforts to promote maternal health and healthy perinatal environments should be prioritized to help reduce early-life asthma exposure for young children.
