Multifactorial Pre-operative Intervention in Diabetes Mellitus

Patients with diabetes that require hospitalization are at increased risk for morbidity and mortality, especially when undergoing surgery. There is some evidence that intensive glucose management during hospitalization may improve outcomes. However, no studies have evaluated intensive diabetes treatment before hospitalization.

Preliminary data from patients having vascular surgery show that those with diabetes have longer hospital stays, more frequent wound infections, and are more likely to require a return to the operating room when compared to patients without diabetes. In particular, insulin-treated patients have even greater peri-operative complications than non-insulin treated patients with diabetes. However, these data also suggest that a clinical trial to test the hypothesis that pre-operative intensive management has significant impact on peri-operative complications would require a very large number of participants to have adequate power.

Thus, our objective is to conduct a pilot and feasibility study to determine whether an intervention that involves intensive pre-operative diabetes management can be successfully implemented and to assess whether trends for benefit are observed. The results of this trial will support the conduct of a definitive study that tests the effectiveness of such an intervention in a larger sample of patients.

This is a randomized, parallel group clinical trial in insulin-treated patients with diabetes mellitus who have been scheduled for elective vascular surgery. We will randomize 46 participants diabetes mellitus: insulin-treated with HbA1c 7.5% or treated with oral agents with an elevated HbA1c who are scheduled for vascular surgery and in whom a 6 week pre-operative delay poses no substantial medical risks, as determined by the staff surgeon. We will exclude individuals with markedly elevated HbA1c or blood pressure; those with recently manifest cardiovascular disease, and those unable to attend regularly scheduled follow-up visits during the pre-operative period.

Participants will be randomized to either continue with usual care or participate in a multifactorial intervention conducted over a 6-week period. During the intervention period, participants will meet with a care manager and/or endocrinologist on at least 3 occasions and have telephone follow-up between these visits. They will receive instruction on lifestyle modifications; measure glucose and blood pressure at home (including the use of a continuous glucose monitoring device on 2 occasions), and receive care management to optimize glucose, blood pressure, and lipid lowering, as appropriate.

The primary outcome measure is the percent of screened participants that are eligible and choose participation Secondary end points will include: participant adherence with the study protocol, change from baseline in A1c and fructosamine, occurrence of wound infections in the 30-day peri-operative period, a composite of death from cardiovascular causes, non-fatal myocardial infarction, coronary artery bypass grafting, percutaneous coronary intervention, nonfatal stroke, or amputation as a result of peripheral ischemia; length of hospital stay; and rate of return to the operating room.