Variables
Demographic data was collected and included: date of birth, age at time
of PSG, age at time of echocardiogram, gender, race, BMI z-score (age
>2 years) / weight for height z-score (age <2
years) at time of echocardiogram, and blood pressure and oxygen
saturations closest to echocardiogram date. Data on medical
comorbidities was collected based on diagnostic billing codes (ICD-10).
Comorbidities studied were prematurity, bronchopulmonary dysplasia,
laryngomalacia, craniofacial anomaly, trisomy 21, neuromuscular disorder
or Arnold Chiari malformation, hypertension, pulmonary hypertension,
feeding dysfunction, and obesity. Surgical history was collected on
adenoidectomy, tonsillectomy or adenotonsillectomy as well as cardiac
surgery and type. Heart defects in all children were noted and broadly
classified into two groups: structural heart disease or no structural
heart disease.