Impact of COVID-19 pandemic on BMI among Spanish allergic children

ABSTRACT

Background: The COVID-19 pandemic has been associated with weight gain among adults and children, and obesity is a risk factor and disease modifier for asthma. The objective of this study was to determine if there was a change in the body mass index (BMI) in pediatric patients with respiratory and allergic diseases, comparing their BMI in 2021 with the one in 2019. Method(s) A retrospective cohort study was performed using the database of the Hospital's Information System, including children under 15 years old from the Pediatric Pneumology and Allergy Unit in the year 2021 who had at least one anthropometric measurement done before March 2020, when lockdown and social distancing measures were enacted in Spain. The main variable was the variation of the BMI, weight, and height of patients before and after lockdown. To prove if the trend was higher or lower than the one detected before the pandemic, these measurements were compared with those obtained during the 5 years prior to 2019 in the same population. Subsequently, a secondary outcome was to evaluate the relationship between the different allergic diseases with weight gain. Result(s) A total of 291 patients were recruited, 37.46% female. 54.98% suffered from asthma, and the most frequent diagnosis was allergic rhinitis. The mean age at the start of the pandemic was 8.67 years old (DT 3.15). The percentage of patients with obesity grew significantly during the pandemic 10.31% versus 16.15%. Therefore, significant increases of BMI were observed with p < 0.05 in patients with obesity, compared to patients with normal weight and overweight. Nevertheless, no differences were found with the increases of BMI that were already detected before the start of the pandemic previous DELTABMI percentile 1.86 (DT 16.32) -DELTA BMI percentile during pandemic 2.71 (DT 15.89), p = 0.477. Children between 5 and 11 years were the most affected group, with an increase of BMI percentile from -2.25 (DT 19.86) to 1.27 (DT 5.43), p = 0.003 after de lockdown. With the Fisher's non-parametric independent test, the relationship between allergic diseases and BMI increase was studied, finding a relationship with the presence of asthma (DELTABMI p = 0.026). Conclusion(s) The pandemic has caused an increase of the obesity rates, especially among children between 5 to 11 years old, and those with asthma. Nevertheless, the BMI increase in the pediatric population was already a reality taking place before the pandemic, without finding changes in this trend in the study.