Outcomes of an Exercise Intervention in Adults With Down Syndrome and Congenital Heart Disease: A Secondary Analysis.

This was an ancillary analysis of a parent study that was not specifically designed or powered to evaluate outcomes by congenital heart disease status. The sample size for participants with congenital heart disease was small (n=36), and the study was not powered to detect differences between exercise frequency arms within this subgroup. The sample was relatively young (average age 25.5 years) and homogeneous (mostly White and non-Hispanic), limiting generalizability to older adults or other racial and ethnic groups. Information on the severity of congenital heart disease was not collected, which may influence exercise tolerance and safety. The clinical significance of some observed changes, such as the increase in diastolic blood pressure, is unclear as values remained within normal ranges. Attrition analysis for fitness testing showed lower completion rates in the congenital heart disease group (55.6%) compared to the no congenital heart disease group (70.0%), though this difference was not statistically significant.

Do not interpret the lack of statistical significance in the comparison of clinically meaningful fitness improvements between groups as evidence that exercise is less effective for those without congenital heart disease. The study was not powered for this specific comparison, and the observed difference (25.0% vs 4.8%) may be due to lower baseline fitness in the congenital heart disease group rather than a differential treatment effect.