Long-term outcomes and predictors of compensatory sweating after bilateral endoscopic thoracic sympathectomy

Abstract Objectives Bilateral endoscopic thoracic sympathectomy is an effective treatment for primary hyperhidrosis, yet the causes of its main side effect, compensatory sweating, remain unclear. This study aimed to identify risk factors for compensatory sweating in a long-term follow-up cohort. Methods Patients who underwent bilateral endoscopic thoracic sympathectomy for primary hyperhidrosis between 2010 and 2023 (n = 98) were interviewed, and preoperative data were collected. Compensatory sweating was classified as mild, moderate, or severe according to the Society of Thoracic Surgeons guidelines. Quality of life was assessed using the Hyperhidrosis Disease Severity Scale from the International Hyperhidrosis Society. Logistic and ordinal Bayesian regression models were applied to analyze associations between predictors, compensatory sweating outcomes, and quality of life. Results The procedure achieved an overall effectiveness of 94.38%, with 34.69% of patients reporting compensatory sweating, predominantly mild (26.53%). Nearly all patients (97.95%) experienced a ≥ 50% reduction in sweating, and 94.89% achieved ≥80% reduction. Higher hemoglobin levels and marijuana protected against compensatory sweating incidence and severity. Conversely, smoking and hyperhidrosis involving both hands and axillae increased compensatory sweating risk. Better quality of life outcomes were correlated with higher hemoglobin levels and female sex, while worse outcomes were associated with older age, higher BMI, and axillary involvement. Conclusions Long-term follow-up highlights key predictors for compensatory sweating, emphasizing the importance of tailored preoperative counseling. Identifying at-risk patients, such as smokers and those with low hemoglobin levels, is essential for improving outcomes and managing expectations in the treatment of primary hyperhidrosis.