To the Editor Using a large database of 212 984 patients with varicose veins and comparing them with a matched cohort without varicose veins, Dr Chang and colleagues found a higher incidence of deep vein thrombosis (DVT) among patients with varicose veins.1 The article does not state what percentage of patients with a diagnosis of varicose veins had received any surgical treatment for them. If the patients had received surgery, what types of treatment had they undergone? This information is important because DVT is a complication following venous surgery, either endovenous or open procedures, with a higher incidence following radiofrequency ablation than other modalities2,3 and also after concomitant phlebectomy.3