Visceral adiposity is related to insulin sensitivity and inflammation in adolescents with obesity and mild sleep disordered breathing

Abstract

Objectives: To evaluate the relationships between adipose tissue distribution, insulin secretion and sensitivity, sleep-disordered breathing, and inflammation in obese adolescents.

Methods: Cross-sectional study of 56 obese adolescents who underwent anthropometric measures, dual-energy X-ray absorptiometry, overnight polysomnography, oral glucose tolerance test (OGTT) and frequently sampled intravenous glucose tolerance test. Correlation and regression analyses were used to assess relationships between adiposity, insulin secretion and sensitivity, measures of sleep-disordered breathing (oxyhemoglobin nadir, SpO₂; apnea hypopnea index, AHI; arousal index, AI; maximum end-tidal CO₂; non-REM sleep duration), and inflammation (high-sensitivity C-reactive protein, hsCRP).

Results: Subjects (55% female) were mean (SD) 14.4 (2.1) years, with BMI Z-score of 2.3 (0.4). AHI was >5 in 10 (18%) subjects and 1< AHI ≤5 in 22 (39%). Visceral adipose tissue area (VAT) was positively correlated with OGTT 1 and 2 h insulin and 1 h glucose, and hsCRP (r=0.3-0.5, p≤0.007 for each). VAT was negatively correlated with sensitivity to insulin (r=-0.4, p=0.005) and SpO₂ nadir (r=-0.3, p=0.04) but not with other sleep measures. After adjustment for BMI-Z, sex, population ancestry, age, and sleep measures, VAT remained independently associated with insulin measures and 1 h glucose, but no other measures of glycemia. SAT was not associated with measures of glycemia or insulin resistance.

Conclusions: Among adolescents with obesity, visceral adiposity was associated with insulin resistance, SpO₂ nadir, and inflammation. The independent association of visceral adiposity with insulin resistance highlights the potential role of VAT in obesity-related chronic disease.

Keywords: adiposity; adolescent; inflammation; insulin resistance; obesity; sleep.