Physical activity restriction for children and adolescents diagnosed with an inherited arrhythmia or cardiomyopathy and its impact on body mass index

Background: Historically, individuals diagnosed with an inherited arrhythmia or cardiomyopathy have been advised to avoid participating in competitive sports. Consequently, these individuals may be more susceptible to weight gain and obesity. Methods: A retrospective longitudinal chart review was performed for a population of children with a genetic or clinical diagnosis of the long-QT syndrome, catecholaminergic polymorphic ventricular tachycardia, hypertrophic cardiomyopathy, or arrhythmogenic right ventricular cardiomyopathy. We recorded the physical activity recommendation, postdiagnosis sports participation, and body mass index (BMI) over time. Results: A total of 109 charts were reviewed. Some level of physical activity restriction was documented for the majority of phenotype-positive children (80%) but was less common for phenotype-negative children (37%) (P < 0.001). Overall, 38% (n = 41) of the study population were reportedly participating in a moderate or high dynamic sports following their diagnosis. Nonetheless, the BMI did not differ over time based on physical activity restriction or sports participation, and the proportion of overweight and obese children at follow-up was consistent with that seen in the Canadian pediatric population. Conclusion: Physical activity restriction was recommended for the majority of phenotype-positive children with an inherited arrhythmia or cardiomyopathy. However, many children continue to participate in competitive sports. Children prescribed physical activity restriction appear to face similar concerns relating to obesity as other Canadian children. This study highlights the need to further assess the effectiveness of physical activity recommendations and its impact on the cardiovascular health.