A Randomized Controlled Trial of Continuous Positive Airway Pressure on Glucose Tolerance in Obese Patients with Obstructive Sleep Apnea.
OBJECTIVE
Obstructive sleep apnea (OSA) is associated with an increased prevalence of metabolic syndrome (MetS), even in patients with morbid obesity. Our goal was to address whether continuous positive airway pressure (CPAP) treatment improved glucose metabolism in this population.


METHODS
A prospective randomized controlled trial was performed in severe OSA patients with morbid obesity without diabetes in two university referral hospitals. Patients received conservative (CT) versus CPAP treatment for 12 weeks. MetS components, homeostasis model assessment of insulin resistance (HOMA-IR) and oral glucose tolerance were assessed at baseline and after treatment.


RESULTS
A total of 80 patients completed the study (42 CPAP and 38 CT patients). After 12 w of CPAP treatment, weight loss was similar in both groups and physical activity, prevalence of MetS, and HOMA-IR did not change in either group. In the CPAP group impaired glucose tolerance (IGT) reversed in nine patients and IGT developed in none, whereas IGT reversed in five patients and IGT developed in five patients in the CT group (P = 0.039 in the Fisher test). Changes in 2-h plasma glucose after glucose load were greater in the CPAP group than in the CT group (CPAP: -0.5 ± 1.5 versus CT: 0.33 ± 1.9, P = 0.007).


CONCLUSIONS
The improvement of glucose tolerance in morbidly obese patients with severe obstructive sleep apnea, without changes in homeostasis model assessment of insulin resistance, supports an improvement in peripheral insulin resistance after continuous positive airway pressure treatment.


BACKGROUND
NCT 01029561.
Sleep Unit, Department of Respiratory Medicine, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Spain.|Bellvitge Biomedical Research Institute (IDIBELL). Area: Inflammatory, Chronic and Degenerative Diseases. Section: Respiratory Medicine. Hospitalet de Llobregat, Spain.|Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.|CIBER Enfermedades Respiratorias (CibeRes) (CB06/06), Spain.
Neus
N
Salord
Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.|CIBER Enfermedades Respiratorias (CibeRes) (CB06/06), Spain.|Sleep Unit, Department of Respiratory Medicine, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
Ana Maria
AM
Fortuna
Sleep Unit, Department of Respiratory Medicine, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Spain.|Bellvitge Biomedical Research Institute (IDIBELL). Area: Inflammatory, Chronic and Degenerative Diseases. Section: Respiratory Medicine. Hospitalet de Llobregat, Spain.|CIBER Enfermedades Respiratorias (CibeRes) (CB06/06), Spain.
Carmen
C
Monasterio
Sleep Unit, Department of Respiratory Medicine, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Spain.|Bellvitge Biomedical Research Institute (IDIBELL). Area: Inflammatory, Chronic and Degenerative Diseases. Section: Respiratory Medicine. Hospitalet de Llobregat, Spain.
Mercè
M
Gasa
Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.|Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain.|CIBER de diabetes y Enfermedades Metabólicas (CIBERDEM), Spain.
Antonio
A
Pérez
Biomedical Department of Internal and Specialistic Medicine (DIBIMIS), University of Palermo, Italy.
Maria R
MR
Bonsignore
CIBER de diabetes y Enfermedades Metabólicas (CIBERDEM), Spain.|Department of Endocrinology and Nutrition, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Spain.
Núria
N
Vilarrasa
CIBER Enfermedades Respiratorias (CibeRes) (CB06/06), Spain.|Sleep Unit. Department of Respiratory Medicine, Hospital Clinic de Barcelona, Barcelona, Spain.
Josep Maria
JM
Montserrat
Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.|CIBER Enfermedades Respiratorias (CibeRes) (CB06/06), Spain.|Sleep Unit, Department of Respiratory Medicine, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
Mercedes
M
Mayos
D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D045422:Continuous Positive Airway Pressure; D005260:Female; D018149:Glucose Intolerance / Q000150:complications* / Q000503:physiopathology / Q000628:therapy*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000503:physiopathology; D008875:Middle Aged; D009767:Obesity, Morbid / Q000150:complications* / Q000503:physiopathology*; D011446:Prospective Studies; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000503:physiopathology / Q000628:therapy*; D015431:Weight Loss
D001786:Blood Glucose; D007328:Insulin
continuous positive airway pressure; glucose tolerance; insulin resistance; obstructive sleep apnea