The prevalence of poor fitness in children in a regional multidisciplinary severe asthma clinic, UK

In our specialist clinic we emphasise the importance of healthy living but evidence around prevalence of obesity & fitness in this group is sparse Aim: To explore the prevalence of obesity & poor fitness levels in our asthma clinic & identify risk factors for poor fitness Method: Database analysis of routinely collected data for children who attended clinic since July 2018. BMI percentiles were calculated according to the National Child Measurement Programme, UK (93rd-97th percentile=overweight, 98th-99th percentile=very overweight). Fitness levels were assessed using the Chester step test, giving a valid approximation of VO2 max score. Poor fitness and overweight/very overweight were compared (chi-square or Person’s correlation) against demographic details, socioeconomic status (Postcode index of multiple deprivation index), and markers of asthma control, airway obstruction, and airway inflammation. Results: 99 children (median 12 years IQR 10-15;64% male),of whom 79 (80%) completed a fitness test. 44/99 (44%) were overweight/very overweight (15/99 (15%) and 29/99 (29%) respectively). 31/79 (39%) had sub-average or very low fitness levels. This was associated with female sex (p 0.047), older age (p 0.017) & baseline BMI category (p 0.03). Poor fitness was not associated with clinical or physiological markers of asthma severity, or socioeconomic status. Conclusion: Obesity & poor fitness are highly prevalent in children with asthma. Those at risk include girls, older teenagers & overweight children. Proactive screening to identify poor fitness should be conducted in clinics managing children with severe asthma.The impact of improved fitness on asthma control should also be explored.