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Exploring the Role of Adipocyte Fatty Acid Binding Protein in the Association of Obstructive Sleep Apnea and Metabolic Dysfunction

This study is ongoing, but not recruiting participants.
Information provided by:
The University of Hong Kong Identifier:
First received: July 29, 2010
Last updated: May 3, 2017
Last verified: May 2017
Adipocyte fatty acid binding protein (A-FABP) is a member of the FABP super family, is abundant in adipocytes and macrophages. Regulatory functions of A-FABP in lipid and glucose metabolism have been described, and it is suggested to play an important role in the pathogenesis of metabolic syndrome.We hypothesize that obstructive sleep apnea (OSA) may upregulate A-FABP production and thus causally contribute to metabolic dysfunction. Our group has recently demonstrated that A-FABP, expressed and secreted from adipocytes, is present in the blood stream .The levels of A-FABP correlated with various metabolic variates in the metabolic syndrome. Furthermore, we have obtained novel data in men with a range of sleep disordered breathing showed that the duration of oxygen desaturation correlated with circulating levels of A-FABP, independent of age and waist/body mass index. The current proposal aims to pursue this finding and further explore the role of A-FABP in the association of OSA and metabolic dysfunction.

Condition Intervention
Obstructive Sleep Apnea Insulin Resistance Metabolic Syndrome Inflammation Device: continuous positive airway pressure

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Randomized Controlled Trial of the Effect of Continuous Positive Airway Pressure on Adipocyte Fatty Acid Binding Protein and Other Metabolic Markers in Obstructive Sleep Apnea

Resource links provided by NLM:

Further study details as provided by The University of Hong Kong:

Primary Outcome Measures:
  • adipocyte fatty acid binding protein [ Time Frame: changes over 4 weeks of CPAP treatment ]
    This will be done with human A-FABP ELISA reagent set (Biovendor Laboratory Medicine Inc., Czech Republic)

Secondary Outcome Measures:
  • serum Insulin and glucose [ Time Frame: changes over 4 weeks of CPAP treatment ]
    Serum insulin will be determined with microparticle enzyme immunoassay on Abbott IMx system (Abbott, Abbott Park, IL). Plasma glucose will be measured by the glucose oxidase method on a Beckman autoanalyzer (Beckman Instruments, Bream, CA). The estimation of insulin resistance by the homeostasis model assessment method (HOMA-IR) will be calculated

  • Lipids and lipoprotein [ Time Frame: changes over 4 weeks of CPAP treatment ]
    Plasma total cholesterol and triglyceride will be determined enzymatically on Hitachi 912 analyzer .

  • serum advanced oxidation protein products AOPP [ Time Frame: changes over 4 weeks of CPAP treatment ]
    measurement of AOPP using a microplate reader by spectrophotometric detection method

  • serum Total plasma 8-isoprostane [ Time Frame: changes over 4 weeks of CPAP treatment ]
    measured by a specific enzyme immunoassay kit

  • serum inflammatory markers [ Time Frame: changes over 4 weeks of CPAP treatment ]

Enrollment: 95
Study Start Date: June 2008
Estimated Study Completion Date: September 2017
Estimated Primary Completion Date: September 2017 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: continuous positive airway pressure
using continuous positive airway pressure (CPAP) device during sleep, for the study period (4 weeks)
Device: continuous positive airway pressure
an device to be used during sleep, which was a nasal mask connected to a device with pressure applied to upper airway
No Intervention: control
observation for the study period (4 weeks, no CPAP)

Detailed Description:

We hypothesize that there are changes in circulating A-FABP level which can be mitigated by effective treatment of OSA.

The aim is to investigate the effect of CPAP treatment of OSA on circulating A-FABP, and the relationship of changes in serum A-FABP with changes in oxidative stress, inflammation and metabolic variates.


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Subjects between 18 - 65 years old
  • Able to understand and give informed written consent

Exclusion Criteria:

  • BMI > 35 kg/m2
  • known diabetes mellitus or hyperlipidemia on treatment
  • known cardiovascular disease except hypertension stable on treatment
  • unstable medical illness
  • need for starting treatment for OSA or other medical conditions immediately
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Please refer to this study by its identifier: NCT01173432

Hong Kong
The University of Hong Kong
Hong Kong, Hong Kong, 852
Sponsors and Collaborators
The University of Hong Kong
Principal Investigator: Mary SM Ip, MD The University of Hong Kong, Queen Mary Hospital
  More Information

Responsible Party: Professor Mary SM Ip, The University of Hong Kong, Queen Mary Hospital Identifier: NCT01173432     History of Changes
Other Study ID Numbers: UW07-178
HKCTR-770 ( Registry Identifier: Clinical trial centre, The University of Hong Kong )
Study First Received: July 29, 2010
Last Updated: May 3, 2017

Keywords provided by The University of Hong Kong:
obstructive sleep apnea
metabolic dysfunction
metabolic syndrome
adipocyte fatty acid binding protein

Additional relevant MeSH terms:
Sleep Apnea Syndromes
Metabolic Syndrome X
Sleep Apnea, Obstructive
Insulin Resistance
Pathologic Processes
Respiration Disorders
Respiratory Tract Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms
Sleep Disorders, Intrinsic
Sleep Wake Disorders
Nervous System Diseases
Glucose Metabolism Disorders
Metabolic Diseases processed this record on September 19, 2017