GLUCOSE-INSULIN METABOLISM IN PATIENTS WITH OBSTRUCTIVE SLEEP APNEA SYNDROME

Abstract

There has been a great interest in the interaction between obstructive sleep apnea (OSA) and impaired glucose-insulin metabolism, but a shared intimate relationship with obesity makes discerning an independent link challenging. The aim of this study was to evaluate the prevalence of glucose abnormalities in patients suspected for OSA, referred to our Sleep laboratory. Two hundred patients with suspected OSA underwent standard polysomnography. Patients who had respiratory disturbance index (RDI) above 15 were diagnosed with OSA. In the morning after polysomnography, fasting blood levels of glucose, insulin and glicolised hemoglobin (HbA1c) were determined, and homeostasis model assessment (HOMA) score was calculated. In the study, both OSA positive and OSA negative patients were divided according to the body mass index (BMI) in two groups: the first group with BMI ≤30 kg/m2 and the second group with BMI >30 kg/m2. OSA positive patients with BMI≤30 kg/m2 had statistically significant higher blood level of insulin and HOMA index when compared to OSA negative patients with BMI≤30 kg/m2. There was no statistical difference in age, glucose and HbA1c level between these two groups of patients. OSA positive patients with BMI>30 kg/m2 had higher blood level of glucose, insulin and HbA1c and higher HOMA index versus OSA negative patients with BMI>30 kg/m2, but without statistically significant differences.This study suggests that OSA could play a significant role in worsening of glucose metabolism in nonobese patients, but in obese patients, extra weight makes the impairment of glucose-insulin metabolism.