Correlation Analysis of Lower Limb Venous Dilation in Patients With Diabetic Foot Ulcers.

Background: Diabetic foot ulcers (DFUs) significantly contribute to disability and increased mortality rates among patients with diabetes. Researches on venous conditions of DFU are rather limited compared to other pathological factors. This study is aimed at investigating the correlation between venous dilation and various clinical and biochemical factors in patients with DFU. Methods: We enrolled 100 patients with DFU and performed Doppler ultrasound examinations of the lower extremity vascular system by a senior ultrasonographer. Clinical and biochemical characteristics were collected, and their correlation with venous dilation was analyzed by Spearman's correlation and multiple linear regression. Results: The diameters of the common femoral vein, femoral vein, great saphenous vein above knee and below knee (GSVa and GSVb), and the small saphenous vein (SSV) were larger on the affected side than those of the unaffected side of the ulcer, especially the superficial veins. Thus, the ratio of diameters of the superficial veins between affected and unaffected sides was calculated for correlation analysis. Fasting blood glucose levels were positively correlated to the ratio of GSVb, while plasma levels of procalcitonin and white blood cells, markers of inflammation, were found to be positively correlated with the ratio of SSV. However, after adjustment, male gender and duration of diabetes were the positive predictors for the changes in the ratio of GSVb, while systolic blood pressure (SBP) was an independent positive predictor for the changes in the ratio of SSV after adjustment. We did not identify a significant correlation between the severity of the ipsilateral dorsal pedis artery stenosis and the ratios of the GSV and SSV. Conclusion: Our findings indicate that venous dilation in the affected lower limb is a common occurrence in patients with DFU. Male gender, duration of diabetes, and SBP, but not localized arterial stenosis or serum inflammatory markers, were independent predictors for venous dilation below the knee. Understanding these correlations could contribute to the broader understanding of diabetes-related venous complications.