Paradox: Patients without diabetes have worse surgical outcomes than diabetics with same hyperglycemia levels, JAMA

The results showed that patients without diabetes with frequent insulin use and near-universal blood glucose testing had worse outcomes than diabetes patients at similar hyperglycemia levels. Insulin was shown to lessen this effect, and broader use may improve outcomes.

"Because neither underuse of insulin nor diabetes misclassification was responsible for perioperative hyperglycemia, the likelihood of a biological mechanism can be considered," Judy Y. Chen, Department of Surgery, University of Washington, Seattle, and colleagues wrote in their study.

In conventional terms, surgical complications tied with perioperative Hyperglycemia are associated with diabetes. Still, prior cohort studies paradoxically have shown that people without diabetes are at a greater risk of complications at similar hyperglycemic levels versus diabetes patients.

The research team, therefore, aimed to describe the association between perioperative Hyperglycemia and complications from surgery in people without diabetes undergoing surgery who received routine insulin administration and blood glucose testing. The team also evaluated the potential correlation of perioperative Hyperglycemia.

The researchers conducted a retrospective cohort study of the National Surgical Quality Improvement Program. It included consecutive patients undergoing vascular, general, and gynecologic operations who were expected to have an admission of at least 48 hours. 140 mg/dL or higher blood sugar levels within 24 hours after surgery was considered Hyperglycemia. The association between Hyperglycemia and complications was assessed, stratified by severity of Hyperglycemia, and adjusted for diabetes status.

The primary outcomes were perioperative Hyperglycemia and postoperative complications, comparing patients with and without diabetes.

The study yielded the following findings:

· A total of 7634 patients (mean age, 53.5 years; 83.3% patients without diabetes and 17.7% patients with diabetes underwent general ([81.3%]), vascular [2.7%], and gynecologic [16%}) operations. Of these, 77% had blood glucose testing (73.5% individuals without diabetes and 99.9% with diabetes).

· Hyperglycemia occurred in 91% with diabetes and 50.7% of patients without diabetes. Of those with blood glucose levels of more than 180 mg/dL, 72.7% received insulin (91% of patients with diabetes who had Hyperglycemia and 61% of patients without diabetes who had Hyperglycemia).

· Adjusted odds of a complication were 83% higher for patients without compared to those with diabetes at a blood glucose level of 140 to 179 mg/dL (odds ratio, 1.83), 49% higher for the blood sugar level of 180 to 249 mg/dL (odds ratio, 1.49), and 88% higher for blood sugar level more than 250 mg/dL (odds ratio, 1.88).

· A similar trend was seen for serious complications. Insulin may reduce the association between Hyperglycemia and complications in patients without diabetes.

"These findings indicate the importance of continued perioperative glycemic monitoring, particularly in those patients without a known history of diabetes, and underscore areas for further inquiry," they conclude.

Reference:

Chen JY, Nassereldine H, Cook SB, Thornblade LW, Dellinger EP, Flum DR. Paradoxical Association of Hyperglycemia and Surgical Complications Among Patients With and Without Diabetes. JAMA Surg. 2022;157(9):765–770. doi:10.1001/jamasurg.2021.5561