A propensity score analysis for comparison of T-3b and VATET in myasthenia gravis

Neurology. 2017 Jul 11;89(2):189-195. doi: 10.1212/WNL.0000000000004082. Epub 2017 Jun 7.

Abstract

Objective: We performed propensity score (PS) models to compare the outcome of patients with myasthenia gravis (MG) submitted to 2 different surgical approaches: extended transsternal (T-3b) or thoracoscopic extended thymectomy (VATET).

Methods: Patients' clinical data were retrieved from the MG database of the C. Besta Neurologic Institute Foundation. In the PS analysis, a matching ratio of 1:1 of the main clinical variables was obtained for the 2 groups of patients and treatment effect was estimated by comparing their outcome.

Results: A total of 210 patients met the inclusion criteria, by having a complete set of clinical data, and were included in the PS model; a matched dataset of 122 participants (61 per group) showed an adequate balance of all the covariates. Our analysis demonstrated that 68.9% of patients who had thymectomy by the VATET technique reached the pharmacologic remission/remission status at 2 years from thymectomy compared to 34.4% of those operated on by the T-3b technique (p < 0.001), had a lower INCB-MG score (p < 0.001), and had less muscle fatigability (p = 0.004). Similar results were found considering only nonthymomatous patients with MG. Results were also confirmed by paired statistical tests.

Conclusions: Our PS matching analysis showed that VATET is a reliable and effective surgical approach alternative to T-3b in patients with MG who are candidates for thymectomy.

Classification of evidence: This study provides Class IV evidence that for patients with MG, VATET is more effective than T-3b thymectomy.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aftercare
  • Aged
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myasthenia Gravis / surgery*
  • Outcome and Process Assessment, Health Care*
  • Propensity Score
  • Remission Induction
  • Sternum / surgery*
  • Thoracoscopy / methods*
  • Thoracoscopy / standards
  • Thymectomy / methods*
  • Thymectomy / standards