Glycemic control is not associated with neurocognitive decline after cardiac surgery.

ABSTRACT

BACKGROUND: Whether perioperative glycemic control is associated with neurocognitive decline (NCD) after cardiac surgery was examined. METHODS: Thirty patients undergoing cardiac surgery utilizing cardiopulmonary bypass (CPB) were screened for NCD preoperatively and on postoperative day 4 (POD4). Indices of glucose control were examined. Serum cytokine levels were measured and human transcriptome analysis was performed on blood samples. Neurocognitive data are presented as a change from baseline to POD4 in a score standardized with respect to age and gender. RESULTS: A decline in neurocognitive function was identified in 73% (22/30) of patients on POD4. There was no difference in neurocognitive function between patients with elevated HbA1c levels preoperatively (p = .973) or elevated fasting blood glucose levels the morning of surgery (>126 mg/dl, p = .910), or a higher maximum blood glucose levels during CPB (>180 mg/dl, p = .252), or higher average glucose levels during CPB (>160 mg/dl, p = .639). Patients with postoperative leukocytosis (WBC ≥ 10.5) had more NCD when compared to their baseline function (p = .03). Patients with elevated IL-8 levels at 6 h postoperatively had a significant decline in NCD at POD4 (p = .04). Human transcriptome analysis demonstrated unique and differential patterns of gene expression in patients depending on the presence of DM and NCD. CONCLUSIONS: Perioperative glycemic control does not have an effect on NCD soon after cardiac surgery. The profile of gene expression was altered in patients with NCD with or without diabetes.