Medline ® Abstract for Reference 9

The therapeutic effects of weight loss were evaluated in 15 hypersomnolent patients with moderately severe obstructive sleep apnea. As patients decreased their body weight from 106.2 +/- 7.3 kg (mean +/- SE) to 96.6 +/- 5.9 kg, apnea frequency fell from 55.0 +/- 7.5 to 29.2 +/- 7.1 episodes/h (p less than 0.01) in non-rapid-eye-movement sleep with an associated significant decline in the mean oxyhemoglobin saturation during the remaining episodes of sleep apnea from 11.9 +/- 2.4% to 7.9 +/- 1.9% (p less than 0.02). Sleep patterns also improved, with a reduction in stage I sleep from 40.2 +/- 7.3% to 23.5 +/- 4.8% (p less than 0.01), and a rise in stage II sleep from 37.3 +/- 7.0% to 49.4 +/- 4.6% (p less than 0.03). In the 9 patients with the most marked fall in apnea frequency, the tendency toward daytime hypersomnolence was decreased (p less than 0.05). No significant changes in sleep patterns occurred in 8 age- and weight-matched control patients who did not lose weight. Moderate weight loss alone can alleviate sleep apnea, improve sleep architecture, and decrease daytime hypersomnolence.