Heavy Tots Who Become Heavy Kids Suffer Increased Asthma Risk

Hefty toddlers who stay overweight until age seven have an increased risk of asthma, but toddlers who lose the extra pounds before then suffer no additional risk, researchers at the Karolinska Institute have found.

The researchers followed a cohort of 2, 075 Swedish children from birth to age eight. They acquired data on the children from frequent parental questionnaires requesting information on environmental exposure and health outcomes. Information on participants’ height and weight was obtained via school health records.

Overall, the researchers found that children who were overweight or obese at age seven had a greater chance of having asthma than their slimmer peers. This increased risk held regardless the weight of the children when they were younger. Children who were overweight at age four but then achieved an average weight by age seven, however, had the same chance for asthma as children who were never overweight.

Approximately 300 children in the cohort were overweight at some point during the study period, but only 122 remained overweight from their first birthday to age seven. In all, 6% of participants had asthma by the end of the study at age eight, including 10% of the children who were overweight at age seven.

Lead researcher Jessica Ohman Magnusson, of the Karolinska Institute in Stockholm, told Reuters Health that overweight toddlers often attain normal weight by age seven, but she noted that parents may need to intervene if their children remain pudgy at age four. She said parents can help their children manage their weight by educating them on how to lead a healthy lifestyle.

Magnusson and her colleagues emphasized that these findings do not support the idea that childhood obesity causes asthma, as overweight toddlers who slimmed down by age seven did not have an increased chance of developing asthma. There is a chance, Magnusson continued, that other factors may help explain why those children who remained overweight were at greater risk of developing asthma.

“Our study indicates that high BMI during the first four years does not increase the risk of asthma at school age among children who have developed a normal weight by age seven years,” the authors write in the abstract of the article. “However, high BMI at age seven years is associated with an increased risk of asthma and sensitization to inhalant allergens.”

The findings are published in the journal Pediatrics.