Short-term outcomes of low-dose versus moderate-dose prednisolone in ocular myasthenia gravis: a retrospective cohort study

Abstract Background The optimal corticosteroid dose for treating ocular myasthenia gravis remains uncertain. Higher doses may increase the risk of adverse effects without providing additional clinical benefit. This study aimed to compare the effectiveness of low-dose versus moderate-dose prednisolone in patients with ocular myasthenia gravis. Methods We conducted a retrospective cohort study of patients diagnosed with ocular myasthenia gravis at a tertiary care center between 2021 and 2024. Patients were categorized based on the mean daily prednisolone dose during the first 8 weeks of treatment into a low-dose group (< 20 mg/day) and a moderate-dose group (≥ 20 mg/day). The primary outcome was treatment response at 2 months, classified as complete remission, major remission, or minor or no response. Multivariable multinomial logistic regression analysis was performed to evaluate the association between prednisolone dose and treatment outcomes, adjusting for potential confounders. Results A total of 62 patients were included, with 31 patients in each group. Baseline characteristics were comparable between groups. Complete remission was observed more frequently in the low-dose group (38.7%) compared with the moderate-dose group (16.1%), whereas major remission was more common in the moderate-dose group (54.9% vs. 35.5%). These differences were not statistically significant (p = 0.158). In adjusted analyses, moderate-dose prednisolone was not significantly associated with clinical outcomes compared with low-dose therapy (adjusted relative risk ratio for complete remission 0.43, 95% confidence interval 0.10–1.95; adjusted relative risk ratio for major remission 1.56, 95% confidence interval 0.44–5.45). The wide confidence intervals indicate substantial uncertainty in the effect estimates. No serious corticosteroid-related adverse events were observed. Conclusions In this retrospective cohort, no statistically significant difference in short-term treatment outcomes was observed between low-dose and moderate-dose prednisolone. However, the observed difference in complete remission rates and the wide confidence intervals indicate substantial uncertainty, and clinically meaningful differences between dosing strategies cannot be excluded. Larger prospective studies are needed to determine the optimal prednisolone dosing strategy for ocular myasthenia gravis. Trial registration Thai Clinical Trials Registry (TCTR): TCTR20251229010