Screening asymptomatic patients with diabetes for unknown coronary artery disease: does it reduce risk? An open-label randomized trial comparing a strategy based on exercise testing aimed at revascularization with management based on pharmacological/behavioural treatment of traditional risk factors. DADDY-D Trial (Does coronary Atherosclerosis Deserve to be Diagnosed and treated early in Diabetics?).

Background: Coronary artery disease is the leading cause of morbidity and mortality in patients with type 2 diabetes. Screening for asymptomatic coronary artery disease with treatment by means of revascularization seems to be an appealing option for prevention. The utility of such a strategy has never been challenged in a randomized trial.

Methods/design: In the present study a cohort of diabetic patients without any symptoms and without known coronary artery disease will be screened at two diabetes outpatients services. Those with intermediate or high risk (equal or greater than 10% according to the Italian risk chart) will be asked to participate and enrolled. They will be seen and followed in order to provide the best adherence to medical therapy. Half of the patients will be randomized to undergo an exercise tolerance testing while the other group will continue to be regularly seen at diabetes outpatients services. Best medical/behavioral therapy will be offered to both groups. Those patients with a positive exercise tolerance testing will be studied by coronary angiography and treated according to the severity of coronary lesions by percutaneous stenting or surgery.The objective of the study is to evaluate the efficacy of the screening strategy aimed at revascularization. A cost-effectiveness analysis will be performed at the end of the follow up.

Discussion: The study will provide useful information about prevention and treatment of diabetic patients at high risk of coronary events. It will be made clearer if detection of silent coronary artery disease has to be recommended and followed by treatment. Given the simplicity of the study protocol, it will be easily transferable to the real world.

Trial Registration: (ClinicalTrials.gov): NCT00547872.