Clinical and cardiorespiratory assessment in children with Down syndrome without congenital heart disease

Objective: To assess the clinical and functional status of a young Down syn drome (DS) population without congenital heart disease. Design: Prospective study of children with DS and control subjects. Setting: Bambino Gesu Children's Hospital, Rome, Italy. Participants and Methods: Forty-two children with DS (mean +/- SD age, 9.8 +/- 3.6 years) underwent genetic, clinical, neuropsychological (IQ), and ca rdiorespiratory evaluation. Cardiorespiratory fitness was assessed with a t readmill test and a lung function test to determine forced vital capacity, first-second forced expiratory volume, and peak expiratory flow. Data were expressed as a percentage of the predicted values for control children. To assess cooperation during exercise testing, we devised a compliance scale a ssigning a score according to the subjects' ability to understand instructi ons, ability to walk and run as required, and need for vocal encouragement. Results: Eighteen (43%) of 42 children with DS were obese, 10 (24%) were sh ort, and 17 (40%) had microcephaly. On the Leiter International Performance Scale, 2 of 35 subjects had a normal IQ score (80-120); all others had low IQ scores (79 to <40). Five subjects did not undergo cardiorespiratory ass essment. Eighteen of 37 subjects completed lung function tests;: the result s for 10 were unremarkable, and results from 8 revealed reduced forced vita l capacity because of poor compliance. The subjects tested had low exercise tolerance (mean +/- SD tolerance percentage, 61% +/- 12%), mild tachycardi a (maximal heart rate, 91% +/- 4%),and a mild hypertensive response (maxima l blood pressure, 89% +/- 8%). Compliance scores correlated significantly w ith exercise time and age hut not with IQ. Conclusions: Clinical and cardiorespiratory assessment is feasible in subje cts with DS without congenital heart disease and should be useful in gaugin g their fitness level for safe physical activity.