Objective evidence that bariatric surgery improves obesity-related obstructive sleep apnea

Surgery. 2007 Mar;141(3):354-8. doi: 10.1016/j.surg.2006.08.012. Epub 2006 Dec 8.


Background: Obstructive sleep apnea (OSA) is associated with obesity. Our aim in this study is to report objective improvement of obesity-related OSA and sleep quality after bariatric surgery.

Methods: Prospective bariatric patients were referred for polysomnography if they scored >or=6 on the Epworth Sleepiness Scale. The severity of OSA was categorized by the respiratory disturbance index (RDI) as follows: absent, 0 to 5; mild, 6 to 20; moderate, 21 to 40; and severe, <40. Patients were referred for repeat polysomnography 6 to 12 months after bariatric surgery or when weight loss exceeded 75 lbs. Means were compared using paired t tests. Chi-square tests and linear regression models were used to assess associations between clinical parameters and RDI; P<.05 was considered statistically significant.

Results: Of 349 patients referred for polysomnography, 289 patients had severe (33%), moderate (18%), and mild (32%) OSA; 17% had no OSA. At a median of 11 months (6 to 42 months) after bariatric surgery, mean body mass index (BMI) was 38 +/- 1 kg/m2 (P<.01 vs 56 +/- 1 kg/m2 preoperatively) and the mean RDI decreased to 15 +/- 2 (P<.01 vs 51 +/- 4 preoperatively) in 101 patients who underwent postoperative polysomnography. In addition, minimum oxygen saturation, sleep efficiency, and rapid eye movement latency improved, and the requirement for continuous positive airway pressure was reduced (P<or=.025). Male gender and increasing BMI correlated with increasing RDI (P<.01) by chi-square analysis. In a multivariate linear regression model adjusted for age and gender, preoperative BMI correlated with preoperative RDI (r=0.27; P<.01).

Conclusions: OSA is prevalent in at least 45% of bariatric surgery patients. Preoperative BMI correlates with the severity of OSA. Surgically induced weight loss significantly improves obesity-related OSA and parameters of sleep quality.

Publication types

  • Clinical Trial

MeSH terms

  • Bariatric Surgery*
  • Female
  • Follow-Up Studies
  • Humans
  • Linear Models
  • Male
  • Obesity / epidemiology*
  • Obesity / surgery*
  • Outpatients
  • Polysomnography
  • Postoperative Care
  • Predictive Value of Tests
  • Preoperative Care
  • Prevalence
  • Prospective Studies
  • Severity of Illness Index
  • Sleep
  • Sleep Apnea, Obstructive / diagnosis
  • Sleep Apnea, Obstructive / epidemiology*
  • Sleep Apnea, Obstructive / surgery*
  • Treatment Outcome