Compensatory Hyperhidrosis After ETS: Temporal Evolution and Predictors

Background: Compensatory hyperhidrosis remains the most significant complication after endoscopic thoracic sympathectomy for primary palmar hyperhidrosis. However, its temporal evolution and long-term predictors are not fully elucidated. Methods: This multicentre retrospective study included 226 patients who underwent bilateral clip-based ETS between 2009 and 2023. Patients were stratified by surgical level: R3 (n=60), R4 (n=72), R2–R4 (n=81), and asymmetric interruption (n=13). Compensatory hyperhidrosis severity was assessed at 6, 12 months, and final follow-up (mean 98 months). Logistic regression identified independent predictors of Compensatory hyperhidrosis, recurrence, and patient satisfaction. Results: Complete palmar dryness was achieved in 84.5% of patients. Compensatory hyperhidrosis occurred in 48.7%, exclusively within the first 6 postoperative months, with no late-onset cases. During long-term follow-up, spontaneous regression of compensatory hyperhidrosis was observed in 28.2% of affected patients. Compensatory hyperhidrosis incidence differed significantly across surgical levels (p=0.011): 38.3% (R3), 55.6% (R4), 63.0% (R2–R4), and 30.8% (asymmetric). Multivariate analysis confirmed multi-level R2–R4 sympathectomy as an independent predictor of compensatory hyperhidrosis (OR=2.18, p=0.042), while single-level R4 interruption provided the lowest persistent compensatory hyperhidrosis burden. Overall satisfaction was 79.6%, and recurrence—not compensatory hyperhidrosis —was the main determinant of dissatisfaction (OR=2.48, p<0.001). Smoking history independently predicted recurrence (OR=2.09, p=0.042). Conclusions: Compensatory hyperhidrosis develops exclusively during the early postoperative period and shows partial spontaneous improvement over time. Multi-level interruption significantly increases compensatory hyperhidrosis risk without improving efficacy, supporting limited single-level approaches (preferably R4). These findings emphasize the importance of surgical level selection, smoking cessation, and realistic postoperative counseling.