Pre-operative optimization of hemoglobin A1c and albumin levels in diabetic patients undergoing spine surgery: A retrospective study

Elevated preoperative hemoglobin A1c (HbA1c) levels and hypoalbuminemia may lead to postponed surgeries to optimize HbA1c levels and to mitigate the risk of associated postoperative complications. If postoperative HbA1c levels deviate, the initial delay and optimization efforts may not yield the intended benefits, ultimately undermining the patient's ability to receive earlier surgical management. A single institution retrospective cohort analysis was conducted including all diabetic patients undergoing spine surgery from July 2023 to June 2024. Patient demographics, duration of diabetes, and preoperative and postoperative HbA1c and albumin levels were collected within 30 days, 90 days, and/or 1 year. Statistical analysis was performed using paired t-tests with significance level of 0.05. Of 99 diabetic patients who underwent spine surgery, the mean age was 68.8 years (SD=11.9) and the mean BMI at time of surgery was 32.27 (SD=6.54). The mean preoperative HbA1c level within 90 days prior to surgery was 7.06 (SD=1.48). Within 30 to 90 days postoperatively compared to baseline, mean HbA1c levels decreased by 0.41 (95% CI [0.071, 0.744]), p = 0.01. Within 1 year postoperatively compared to baseline, mean HbA1c levels decreased by 0.21 (95% CI [-0.017, 0.438]), p = 0.06. The mean preoperative serum albumin level within 30 to 90 days prior to surgery was 4.06 (SD=0.50) and the mean postoperative serum albumin level within 30 to 90 days following surgery was 3.69 (SD=0.58). Within 30 to 90 days postoperatively compared to preoperative levels, albumin levels decreased significantly by 0.34 (95% CI [0.21, 0.48]), t(48) = 5.22, p=0.001. The minor fluctuations in HbA1c levels demonstrate that delaying surgeries for preoperative HbA1c optimization does reflect improved postoperative glycemic maintenance in diabetic patients undergoing spine surgery, further demonstrating the benefit of delaying surgeries for preoperative optimization of these patient specific factors to reduce potential complications that may occur in the postoperative tissue healing period.