The treatment with or without prednisolone in adults aged ≥ 70 years with myasthenia gravis: a retrospective cohort study.

INTRODUCTION: This retrospective, single-center cohort study aimed to compare clinical outcomes, including time to minimal manifestations (MM)-defined as the absence of functional limitations from MG symptoms in daily activities, even with mild muscle weakness on examination-or better status, between patients aged ≥70 years with MG treated with PSL alone or with calcineurin inhibitors (CNIs), and those treated with CNI alone. METHODS: Twelve patients with acetylcholine receptor antibody (AChR-Ab)-positive MG aged ≥70 years were included (the PSL group, n = 7; the CNIs group, n = 5). Changes in the MG Activities of Daily Living scale (MG-ADL) and Quantitative MG (QMG) scores from admission to discharge were evaluated using least-squares mean estimates. Longitudinal changes in AChR-Ab titers over one year were analyzed using a mixed-effects model for repeated measures. The time to MM was assessed using Kaplan-Meier analysis. RESULTS: The MG-ADL scores improved in both groups, with a greater change in the PSL group. QMG scores improved in the PSL group, while no significant change was observed in the CNIs group; however, discharge QMG scores and changes did not differ significantly between the groups. No differences were observed in AChR-Ab titers or the cumulative incidence of MM. All patients in both groups achieved MM or better status within one year. DISCUSSION: In this cohort of patients aged ≥70 years with MG, favorable outcomes were observed, regardless of PSL use. These findings highlight the clinical heterogeneity among older patients with MG and underscore the need for individualized treatment approaches.