A Study Comparing Standard Care for Diabetes to Case-managed Care for Diabetes in Patients With Coronary Artery Disease

Patients with diabetes have a higher incidence of coronary artery disease and a worsened cardiac prognosis. Death from cardiovascular disease accounts for about 70% of all diabetes-related deaths (Booth, 2003). Diabetes is also a common problem among hospitalized cardiac patients. In Ontario, from 1995 to 1997, nearly 1/3 of the 104,471 patients admitted for acute myocardial infarction had diabetes (Booth, 2003). In these patients, hyperglycemia remains a marker for poor outcome despite improvements in coronary care (Wahab, 2002; Capes, 2000).

Several important questions regarding the diabetes care of cardiac patients admitted to hospital wards are yet to be answered. First, it is not known if better glycemic control during the ward phase of hospitalization in itself improves short-term outcomes. Second, assuming that short-term glycemic control is beneficial, it is not known which interventions are effective in accomplishing this. Third, assuming that putting more resources into the management and education of patients with diabetes will translate into long term benefits, it is not known whether this should be done during the "window of opportunity" provided by a cardiac admission or whether this intervention will be more effective if it is deferred until after discharge.

These critical treatment dilemmas have prompted the proposal for the GLUCOSE Pilot Study, a randomized, controlled study to examine the effectiveness of case-managed diabetes care using a multidisciplinary team approach in patients with diabetes admitted to manage concomitant ischemic heart disease. We have designed this protocol to study the effectiveness of case-managed diabetes care by a specialized endocrinology team and compare it to usual care as delivered by the attending cardiologist. Patients will be randomized to specialized endocrinology care or usual care at the time of their admission to the ward. The short-term outcome will be glycemic control of cardiac patients with diabetes while they are admitted to a cardiology ward. In order to compare this with a more typical model of post-discharge care, patients will be re-randomized at the time of discharge into case-managed or usual care groups. The long-term (primary) outcome will be glycemic control and risk factor reduction at 6 months. This factorial design will allow us to compare several treatment models and determine which is the most efficient and effective way to achieve the best long-term diabetes control and risk factor management in our patients.

Inclusion criteria

• Diabetes Mellitus, type 2, as defined by at least one of the following:

• Previous diagnosis of diabetes
• two glucose levels consistent with diabetes (fasting glucose >7.0 mmol/L or random glucose >11.0 mmol/L )
• HbA1C > 6.5% using DCCT standardized methods And

Coronary Disease, as defined by at least one of the following:

• Admitting diagnosis of acute coronary syndrome defined by 2/3 of typical history, enzyme changes, dynamic ECG changes
• Prior history of acute coronary syndrome defined as above
• Previously documented myocardial infarction
• Previous coronary revascularization procedure
• Coronary artery disease defined by coronary angiography
• Exercise or persantine nuclear perfusion imaging positive for ischemia

Exclusion criteria

• Refusal to enter the study
• Inability to understand consent forms and provide informed consent
• Anticipated length of non-ICU hospital stay less than 48 hours
• Diabetes Mellitus, type 1