A positive correlation of severity of
sleep-disordered breathing with morning fasting
insulin levels, which is independent of
obesity, was reported in adults and obese children. We hypothesized that both severity of
sleep-disordered breathing and relative body mass index predict fasting
insulin and homeostasis model assessment (HOMA) index values in nonobese children with habitual
snoring. One hundred and ten subjects with habitual
snoring (median age, 6 years; range, 2-13 years) underwent polysomnography and measurement of morning fasting
insulin and
glucose levels. The HOMA index was calculated. Thirty children had an
apnea-hypopnea index (AHI) >/= 5 episodes/hr (median, 7.8 episodes/hr; range, 5-42.3 episodes/hr), and 80 subjects had an AHI < 5 episodes/hr (median, 1.9 episodes/hr; range, 0.2-4.9 episodes/hr).
Insulin and HOMA index values were similar in children with AHI >/= 5 episodes/hr (median
insulin, 4.9 mU/l; range, 1.66-19.9 mU/l; and median HOMA, 1; range, 0.36-4.95) and in subjects with AHI < 5 episodes/hr (median
insulin, 5.8 mU/l; range, 0.74-41.1 mU/l; and median HOMA, 1.3; range, 0.13-9.72) (P > 0.05). No significant correlations were identified between
insulin or HOMA index values and any polysomnography indices (P > 0.05). When multiple linear regression was carried out, relative body mass index was a significant predictor of log-transformed
insulin levels or HOMA index values, but AHI and percentage of sleep time with saturation <95% were not. In conclusion, contrary to findings in adults and in obese children, severity of
sleep-disordered breathing is not a significant predictor of fasting
insulin or HOMA index values in nonobese children with habitual
snoring.