title: High Adherence to CPAP Treatment Does Not Prevent the Continuation of Weight Gain among Severely Obese OSAS Patients.
abstract: OBJECTIVE
  Obstructive sleep apnea syndrome (OSAS) patients benefit from continuous positive airway pressure (CPAP) treatment in a dose-response manner. We determined adherence and weight control, as well as their predictors, among long-term CPAP users.
  
  
  METHODS
  Cohort of 1,023 OSAS patients had used CPAP on average of 6.6 ± 1.2 years. BMI was determined at baseline and at follow-up visits. There were 7.4 ± 1.7 BMI and 6.5 ± 1.8 CPAP usage measurements per patient on average. Using the Bayesian hierarchical model, we determined the patients' individual trends of BMI and adherence development. Patients with significantly increasing or decreasing trends were identified at the posterior probability level of > 90%.
  
  
  RESULTS
  The mean age in the cohort was 55.6 ± 9.8 years, BMI 33.5 ± 6.4 kg/m(2), apnea-hypopnea index 33.7 ± 23.1, and CPAP usage 6.0 ± 1.8 h/day. The majority of patients had no significant change in BMI (mean annual weight gain 0.04 ± 0.29 kg/m(2)) or CPAP adherence (mean annual increase 11.4 ± 7.0 min/day). However, at the individual level, 10% of the patients showed significant annual weight gain (0.63 ± 0.35 kg/m(2)) during the 5-year follow-up period. At baseline these patients were already more severely obese (mean BMI 40.0 ± 5.9 kg/m(2)) despite being younger (mean 50.9 ± 9.5 years) than the rest of the cohort.
  
  
  CONCLUSIONS
  In the majority of CPAP-treated OSAS patients, weight did not significantly change but gained slightly slower than in age-matched population in general. However, in 10% of patients, high adherence to CPAP treatment did not prevent the continuation of weight gain. These patients present a high-risk group for OSAS-related multimorbidity later in life.
authors.affiliation: Division of Medicine, Department of Pulmonary Diseases, Turku University Hospital and University of Turku, Finland.
authors.forename: Minna
authors.initials: M
authors.lastname: Myllylä
authors.affiliation: Auria Biobank, Department of Pathology, Hospital District of Southwest Finland and University of Turku, Finland.
authors.forename: Samu
authors.initials: S
authors.lastname: Kurki
authors.affiliation: Division of Medicine, Department of Pulmonary Diseases, Turku University Hospital and University of Turku, Finland.|Sleep Research Centre, Department of Physiology, University of Turku, Finland.
authors.forename: Ulla
authors.initials: U
authors.lastname: Anttalainen
authors.affiliation: Division of Medicine, Department of Pulmonary Diseases, Turku University Hospital and University of Turku, Finland.|Sleep Research Centre, Department of Physiology, University of Turku, Finland.
authors.forename: Tarja
authors.initials: T
authors.lastname: Saaresranta
authors.affiliation: Division of Medicine, Department of Pulmonary Diseases, Turku University Hospital and University of Turku, Finland.
authors.forename: Tarja
authors.initials: T
authors.lastname: Laitinen
mesh_terms: D045422:Continuous Positive Airway Pressure / Q000706:statistics & numerical data*; D005260:Female; D005387:Finland; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D010349:Patient Compliance / Q000706:statistics & numerical data*; D017286:Polysomnography; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000628:therapy*; D015430:Weight Gain
keywords: adherence; continuous positive airway pressure therapy; individual development; observational study; obstructive sleep apnea syndrome; weight control