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

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

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.

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 other metabolic biomarkers and cardiovascular parameters

Inclusion Criteria:

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

Exclusion Criteria:

• BMI > 35 kg/m2, and features of obesity hypoventilation syndrome
• 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