Obstructive sleep apnea in obese adolescents referred for bariatric surgery: association with metabolic and cardiovascular variables

BACKGROUND: obstructive sleep apnea syndrome (OSA) is a well-described disease entity in adults, with a higher prevalence in severely obese individuals, while at the same time associated with several comorbidities independently of BMI. Literature regarding OSA in severely obese adolescents is qualitatively and quantitatively limited, possibly resulting in suboptimal diagnosis and treatment.

METHODS: polysomnographic, demographic, anthropometric, and comorbidity-related data were prospectively collected in 56 adolescents with morbid obesity refractory to conservative treatment who presented for surgical therapy. Differences between adolescents with no/mild (apnea-hypopnea index (AHI) 0-4.9) and moderate/severe OSA (AHI ≥ 5.0) were evaluated using independent-samples t, chi-square or Fisher's exact tests. Multivariable linear regression analysis was performed to evaluate the association of several variables with AHI, corrected for BMI z-score.

RESULTS: of the 53 included subjects, 48 (90.6%) showed some degree of sleep disordered breathing and 20 (37.7%) had moderate/severe OSA. Patients with moderate/severe OSA had on average a higher neck circumference (42.4 versus 40.1 cm, p = 0.008), higher BMI z-score (3.7 versus 3.4, p = 0.003), higher plasma triglyceride level (2.2 versus 1.5 mmol/L, p = 0.012), and lower IGF (29.6 versus 40.2 mmol/L, p = 0.010) than those with no/mild OSA. BMI z-score and plasma triglyceride levels were independently related to AHI.

CONCLUSIONS: OSA is highly prevalent amongst morbidly obese adolescents and is strongly associated with BMI z-score. Elevated plasma triglyceride levels are associated with AHI, independent of BMI z-score.