Objective: Obstructive sleep apnea (OSA) and snoring are known independent risk factors for insulin resistance. Microalbuminuria is an early marker of diabetic nephropathy and an independent risk factor for cardiovascular disease. The aim of our study was to search the prevalence of self-reported snoring and high-risk pre-test OSA diagnosis in diabetic patients and search the influence of snoring on microalbuminuria.
Methods: A total of 237 diabetic patients (mean age, 58.6 ± 12.4 years; 126 males), were asked to complete the Berlin Questionnaire that includes questions about snoring, witnessed apnea, tiredness, history of high blood pressure and/or BMI < 30 kg/m(2). Also, their past and current medical records were reviewed for their medications, diabetic control, and complications like neuropathy, retinopathy, and microalbuminuria.
Results: According to the Berlin Questionnaire, a high pre-test probability for the diagnosis of OSA was found in 47.3% of the patients. Snoring was detected in 60.3% of the patients. The mean Epworth Sleepiness Scale score was 7.8 ± 4.6 and 31.6% of the patients reported excessive daytime sleepiness. We found that the both BMI and waist circumferences were significantly associated with snoring and high-risk pre-test OSA. There were no differences for age, gender, fasting glucose, HbA1c, and lipid panels between snorers and non-snorers, and between high-risk pre-test OSA and low-risk pre-test OSA patients. Microalbuminuria was significantly more common in patients who snore. Although snoring was independently associated with microalbuminuria, there were no differences between groups for other microvascular diabetic complications.
Conclusion: Prevalence of OSA-related symptoms was very common in diabetic patients and further prospective studies are needed to elucidate the role of OSA's effect on diabetic control and complications.