BackgroundSleep disordered breathing (SDB) is a widespread disorder with a wide range of harmful outcomes including obstructive sleep apnea (OSA), central sleep apnea (CSA), or sleep-related hypoventilation.PurposeThe aim of the present study was to screen for the occurrence of sleep apnea syndrome in patients with type 2 diabetes mellitus (DM) and to evaluate the relation between the presence of sleep apnea and the level of glycemic control.MethodsThis was a prospective clinical study that enrolled 59 patients who were previously diagnosed as type 2 DM. Sleep study level IV was done using overnight recording of oxygen saturation and pulse.ResultsAmong the studied patients, 42 were females and 17 were males, Their mean age was 59.76 ± 11.13 years. Obstructive sleep apnea was diagnosed in 46 patients (78%). Thirty three (86.8%) patients among those with uncontrolled glycemic level were diagnosed as OSA, whereas 13(61.9%) patients with controlled glycemic level were diagnosed as OSA showing statistically significant difference, p = 0.047. There was no correlation between either HbA1c, age, Mallampati score, or BMI and ODI but there was a correlation between STOP-BANG questionnaire and ODI (P = 0.036). The variables that were significantly related to presence of OSA, were comorbidities, ESS, Mallampati score, STOP-BANG, and sleep symptoms (nocturia and snoring) P value (0.029), (0.031), (0.022), (0.005), (0.049), and (0.012), respectively.ConclusionPatients with type 2 diabetes showed a significant high prevalence of OSA. With significant higher prevalence among patients with uncontrolled DM versus controlled DM.