The Duke Myasthenia Gravis Clinic Registry: II. Analysis of outcomes

Muscle Nerve. 2023 Apr;67(4):291-296. doi: 10.1002/mus.27794. Epub 2023 Feb 20.

Abstract

Introduction/aims: The Duke Myasthenia Gravis (MG) Clinic Registry contains comprehensive physician-derived data on patients with MG seen in the Duke MG Clinic since 1980. The aim of this study was to report outcomes in patients seen in the clinic and treated according to the International Consensus Guidance statements.

Methods: This is a retrospective cohort study of patients initially seen after 2000 and followed for at least 2 years in the clinic. Treatment goal (TG) was defined as achieving MGFA post-intervention status of "minimal manifestations" or better; PIS was determined by the treating neurologist. Time-to-event analysis, including Cox proportional hazards modeling, was performed to assess the effect of sex, acetylcholine receptor antibody (AChR-Ab) status, age at disease onset, distribution (ocular vs generalized), thymectomy, and thymoma on the time to achieve TG.

Results: Among the 367 cohort patients, 72% achieved TG (median time less than 2 years). A greater proportion of patients with AChR-Abs and thymectomy achieved TG and they did so sooner than patients without these antibodies or thymectomy. Otherwise, there were no significant differences in these findings within the tested subgroups. The disease duration at the first Duke Clinic visit was shorter in patients who achieved TG than in those who did not.

Discussion: These results demonstrate outcomes that can be achieved in patients with MG treated according to the current Consensus Guidance statements. Among other things, they can be used to determine the added value and potential role of new treatment modalities developed since 2018.

Keywords: disease registry; myasthenia gravis; outcomes; time-to-event analysis; treatment.

MeSH terms

  • Autoantibodies
  • Humans
  • Myasthenia Gravis* / diagnosis
  • Myasthenia Gravis* / therapy
  • Receptors, Cholinergic
  • Retrospective Studies
  • Thymectomy / methods
  • Thymus Neoplasms*
  • Treatment Outcome

Substances

  • Receptors, Cholinergic
  • Autoantibodies