title: Effects of laparoscopic adjustable gastric banding on sleep and metabolism: a 12-month follow-up study.
abstract: BACKGROUND
  Obstructive sleep apnea is commonly associated with metabolic changes and obesity, and changes in body weight by either medical or surgical approaches have been considered to affect the severity of sleep apnea and appetite-controlling hormones. This prospective study evaluated the effect of weight loss induced by laparoscopic adjustable gastric banding (LAGB) surgery on respiratory disturbance during sleep, oxygen saturation levels, sleep architecture, and leptin and ghrelin levels.
  
  
  METHODS
  Participants were patients at a university-based medical center surgical weight loss program. All participants with a body mass index > 30 kg/m(2) undergoing LAGB surgery for weight reduction were offered the opportunity to participate in the study. Procedures included overnight polysomnography followed by fasting hormone levels at baseline and 12 months postoperatively.
  
  
  RESULTS
  Thirty subjects (10 men, 20 women) of mean age 44.0 ± 12.5 years were recruited. At 12 months postoperatively, mean excess weight loss was 44.4% ± 14%. The apnea-hypopnea index decreased from 34.2 ± 35 to 19.0 ± 21.7 events per hour (P < 0.0001), while leptin levels decreased from 24.5 ± 17.42 pg/mL to 11.6 ± 10.6 pg/mL (P = 0.02). Ghrelin levels did not change substantially. Nadir oxygen saturation levels increased from 81% to 84% at 12 months (P = 0.03). Mean oxygen saturation improved and was positively correlated with ghrelin levels at both time points (r = 0.39, P = 0.07, and r = 0.60, P = 0.01).
  
  
  CONCLUSIONS
  LAGB surgery was associated with 44.4% excess weight loss at 12 months, accompanied by a 33.7% improvement in apnea-hypopnea index as well as a reduction in leptin levels by 31.7% in this group. An association between ghrelin and mean oxygen saturation was seen and deserves further investigation.
authors.affiliation: Weill Cornell Medical College and New York Presbyterian Hospital, New York, NY.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Krieger
authors.forename: Heekoung
authors.initials: H
authors.lastname: Youn
authors.forename: Frank
authors.initials: F
authors.lastname: Modersitzki
authors.forename: Ya-Lin
authors.initials: YL
authors.lastname: Chiu
authors.forename: Linda M
authors.initials: LM
authors.lastname: Gerber
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Weinshel
authors.forename: Christine R
authors.initials: CR
authors.lastname: Fielding