Comment on: Effectiveness of Endovenous Radiofrequency Ablation for Elderly Patients with Varicose Veins of Lower Extremities.

To the Editor: I read the article titled “Effectiveness of Endovenous Radiofrequency Ablation for Elderly Patients with Varicose Veins of Lower Extremities” by Kiyoshi Tamura et al.1) It was a pleasure to read this manuscript. The authors have displayed great precision in highlighting various aspects. However, I would like to address some misunderstandings that have come to my attention and improvements that can aid in future similar studies. First, there is a discrepancy in defining diabetes mellitus (DM) and chronic kidney disease (CKD) in patients used in the study. Kiyoshi Tamura et al.1) defined DM as the recent use of antidiabetic drugs, fasting blood glucose >126 mg/dL, and/or hemoglobin A1c >6.5%, and although most of the criteria used in the definition adheres to the American Diabetes Association, they can add 2-h plasma glucose level of 200 mg/dL and/or a random plasma glucose of 200 mg/dL. In addition, discrepancy with the use of antidiabetic drugs is not only used in patients with DM but also in prediabetic patients using antidiabetic drugs, as recent studies have shown that oral antidiabetic drugs do assist prediabetics in returning to normoglycemic states.2) Chronic kidney disease was defined as having an estimated glomerular filtration rate less than <30 mL/min/1.73 m; however, a study was conducted to give a definition for chronic kidney disease that can be internationally recognized and implemented according to clinical practice guidelines by the Kidney Disease: Improving Global Outcomes (KDIGO), which states “CKD is defined as kidney damage or glomerular filtration rate (GFR) <60 mL/min/1.73 m for 3 months or more, irrespective of cause.2) Kidney damage in many kidney diseases can be ascertained by the presence of albuminuria, defined as albumin-to-creatinine ratio >30 mg/g in two of three spot urine specimens.” Hence, it would be more appropriate for the study conducted.3) Having a broader and more precise definition for CKD by including a period of time would allow better understanding of CKD present in the persons studied, which can also have effects on complications as a result on the effectiveness of endovenous radiofrequency ablation therapy. One of the postoperative major complications considered in the study was endothermal heat-induced thrombosis (EHIT); however, to classify the injuries they used only the Kabnick classification. For improvement, the American Venous Forum (AVF) and Society for Vascular Surgery combines the Kabnick and Lawrence classification into AVF EHIT classification to properly manage and treat EHIT, and hence, it would have provided a better understanding to the level of degree of injury caused due to EHIT.4) Varicose veins in the lower extremities can affect both great and small saphenous veins; however, in the study they did not elaborate on whether the radiofrequency ablation therapy was done on great or small saphenous veins. Further research on the effectiveness of endovenous radiofrequency ablation therapy and the postoperative complications as a result of having a comparison on radiofrequency venous ablation on great and small saphenous veins can provide a better understanding on the effects of endovenous radiofrequency ablation therapy on varicose veins.5) Another postoperative complication that can be considered to improve the study is including the healing time of endovenous radiofrequency ablation therapy in the older population because the healing time can give an overall impression of the effectiveness and also with age, healing becomes a slower process.6) I applaud the authors for their Online September 16, 2023 doi: 10.3400/avd.co.23-00052