The study aims to examine if non-invasive imaging of the coronary arteries by CT angiography using an intra-venous injection of X-ray contrast medium in asymptomatic patients with adult onset diabetes mellitus can predict the risk of developing coronary heart disease.

Patients having diabetes mellitus are at increased risk for the development of coronary heart disease. Available tests do not accurately predict which diabetic patients are at greatest risk of suffering from a coronary event. The recent development of coronary CT angiography allows non-invasive imaging of both coronary narrowing and of disease (atheroma) in the coronary arterial wall at an earlier stage of the disease before the development of coronary arterial narrowing.

In this study we will collect all the readily available patient medical data relating to diabetes and its complications and other coronary artery disease risk factors. In addition patients will be referred for exercise stress testing and for eye examinations. The coronary CT angiogram will be carefully examined for early signs of coronary artery disease. In the event of a finding on the CT scan requiring medical therapy this will be communicated to the patient and his treating physician. In the event of a finding on the stress test or CT scan requiring further medical work-up the patient will be referred to the cardiology clinic.

In general patients will be followed in the regular diabetic clinic and by their family practitioners.

In the event of any acute symptoms over the next few years possibly related to heart disease and requiring emergency room examination patients will be requested to report to the emergency room at the hospital at which the CT study was performed whenever possible.In such an event a repeat CT scan will be performed to examine if any new findings are present. In the event of any new complaints requiring referral to an out of hospital clinic patients will be referred for further assessment to the cardiology clinic and a repeat CT scan may be performed if deemed relevant.

Outcomes of all patients will be examined at 2 years or later using computerized databases. Patients undergoing hospitalization during the follow up period of at least 2-3 years will be contacted by the study staff to obtain further details of the event and hospital findings .

An analysis wil be performed of the value of CT angiography in relation to the traditional risk factors and other available medical data in the prediction of later coronary heart disease and other vascular events.

Inclusion Criteria:

• Type II diabetes mellitus
• No symptoms of coronary heart disease
• At least one additional risk factor for coronary artery disease

Exclusion Criteria:

• Known coronary artery disease
• Kidney failure if more than mild
• Allergy to iodinated X-ray contrast media
• Chronic atrial fibrillation

Type 2 diabtes mellitus, age 55-74 yrs, no known coronary artery disease