The effect of long-term glycemic burden on the incidence of diabetic foot ulcers: A retrospective study.

Background: This study aimed to examine the association between mean cumulative glycemic burden (MCGB) and variability cumulative glycemic burden (VCGB) with diabetic foot ulcers (DFUs).

Methods: Participants were followed up at least 4 times with 4 recorded glycosylated hemoglobin (HbA1c) measurements. Glycemic burden during follow-up period was defined as the trapezoidal areas enclosed by the HbA1c measurements taken during two consecutive visits and the responding time interval. MCGB was calculated by dividing sum of total trapezoidal areas by the period of follow-up. VCGB was defined as the standard deviation of the trapezoidal areas divided to the mean of trapezoidal areas. To identify the association between MCGB and VCGB with DFUs, a Cox regression analysis was conducted.

Results: Among 1876 diabetic patients, 138 (7.4 %) developed foot ulcers. As MCGB increased across quartiles, DFUs incidence also rose significantly (3.2 % to 16.0 %, P < 0.001). Similarly, the prevalence of DFUs increases with increasing quartiles of mean HbA1c level (3.2 % to 16.2 %; P < 0.001). When assessing VCGB, ulcer incidence gradually increased with the quartiles increased (P = 0.040), but HbA1c variability did not follow a similar trend (P = 0.133). Multivariable Cox regression analysis indicates that compared to the first quartile, both MCGB and VCGB in the fourth quartile significantly increase the risk of DFUs (HR = 2.99 and 5.29, respectively).

Conclusions: Elevated MCGB and VCGB correlate positively with DFUs. In clinical practice, lowering blood glucose levels and reducing glycemic variability are both crucial for reducing the occurrence of diabetic foot ulcers.