T2-sparing vs T2-including sympathectomy for hyperhidrosis: a meta-analysis on compensatory sweating

BACKGROUND: Sympathectomy is the definitive treatment for primary hyperhidrosis, offering high success rates. However, compensatory sweating (CS) remains a frequent and distressing complication. The level of ganglionic resection, particularly the inclusion of T2, may influence CS incidence, but evidence remains inconsistent. METHODS: A systematic search of PubMed, Embase, and the Cochrane Library was conducted up to July 2025, to identify studies comparing T2-sparing versus T2-including sympathectomy for primary hyperhidrosis. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using random-effects models. Heterogeneity was assessed using the I2 statistic. For outcomes with significant heterogeneity, leave-one-out sensitivity analyses were performed. RESULTS: Eleven studies involving 3,090 patients were included. Of these, 47.2% underwent T2-sparing sympathectomy and 52.8% underwent T2-including procedures. T2-sparing sympathectomy was associated with a significantly lower incidence of overall CS (OR 0.38; 95% CI 0.21-0.67; p = 0.0009; I2 = 65%) and severe CS (OR 0.43; 95% CI 0.28-0.64; p < 0.0001; I2 = 19%). Subgroup analyses confirmed consistent results across both randomized and non-randomized studies, as well as across short-term (≤ 12 months) and long-term (> 12 months) follow-up periods. Sensitivity analyses confirmed the robustness of the findings. No publication bias was detected. CONCLUSIONS: T2-sparing sympathectomy was associated with a significantly lower incidence of CS. These findings support avoiding T2 when feasible to minimize postoperative morbidity. Further prospective studies are needed to confirm these results.