Sleep Apnea, Coronary Atherosclerosis and Heart Failure in Diabetes Patients With Nephropathy (SLEEP) is a controlled trial involving diabetic patients with check-ups at Steno Diabetes Center Aarhus, Nyre-Diabetes Klinikken and Nyremedicinsk Klinik. A total of 80 patients (40 patients without sleea apnea and 40 with moderat/severe sleep apnea) is included in the study. 

The aim of the study is to establish the association between obstructive sleep apnea (OSA), coronary calcification and heart failure in patients with diabetic kidney disease. The basic hypothesis of the study is that patients with diabetic kidney disease and concurrent OSA have a higher prevalence of coronary calcification and heart failure compared to patients without OSA.