Insulin resistance in obstructive sleep apnea

Introduction: OSA is a common condition that is characterized by intermittent and recurrent pauses in respiration results in multiple cycles of hypoxia/reoxygenation with an increased production of reactive oxygen species (ROS). Aim of work: Is to assess serum insulin level and insulin resistance in obese patients with and without OSA. Subjects and methods: Study was performed on 51 obese subjects who had been referred to the Chest Department of Kasr Alaini Hospital with clinical suspicion of OSA in order to perform polysomnography. They were classified into two groups; cases: consist of 33 obese patients who were diagnosed as obstructive sleep apnea (OSA) and controls: consist of 18 obese subjects, without OSA as a control group. The two groups were subjected to polysomnographic study, serum insulin by ELISA and assessment of insulin resistance by calculation of HOMA index. Results: There was statistically highly significant increase in Epworth sleepiness scale (ESS) among cases compared to controls. As regards the polysomnographic data, there was statistically highly significant increase in AHI, desaturation index and duration of desaturation <90% among cases compared to control subjects. Regarding minimal O-2 sat% and average O-2 sat% were lower in cases than in the control subjects and this reduction was statistically significant. There was statistically highly significant increase in serum insulin, HOMA index among cases as compared to controls. Conclusion: Insulin resistance in OSA is related to sleep associated hypoxemia and hypoxic stress. (C) 2014 Production and hosting by Elsevier B. V. on behalf of The Egyptian Society of Chest Diseases and Tuberculosis.