Early Diagnosis and Intervention Are Needed for a Reasonable Prognosis of Thromboangiitis Obliterans.

Background: Thromboangiitis obliterans (TAO) poses a higher risk of amputation than atherosclerosis obliterans. It is characterized by onset at a relatively young age. There are currently no clear treatment guidelines for TAO other than smoking cessation. In this study, we aimed to identify factors that could influence a favorable prognosis of TAO. Methods: From January 2009 to December 2019, we retrospectively reviewed the initial symptoms, characteristics, treatments, and disease course of 37 patients (45 limbs) with TAO. Logistic regression analysis was performed to investigate factors affecting the course of symptoms that persisted or worsened despite treatment. Results: Patients' mean age was 37.2±11.4 years, and all patients were men. The mortality rate was 0% during the follow-up period (76.9±51.1 months). All patients were smokers at the time of diagnosis, and 19 patients (51.4%) successfully quit smoking during treatment. When comparing the Rutherford categories before and after treatment, 23 limbs (51.1%) showed improvement, the category was maintained in 11 limbs (24.4%), and 11 limbs (24.4%) worsened. Symptom persistence or exacerbation despite treatment was associated with a higher initial Rutherford category (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.04-2.42; p=0.03) and a higher score of the involved below-knee artery at the time of diagnosis (OR, 2.26; 95% CI, 1.10-4.67; p=0.03). Conclusion: The degree of disease progression at the time of diagnosis significantly affected patients' prognosis. Therefore, early diagnosis and intervention are important to improve the course of TAO.