Nomogram for short-term outcome assessment in AChR subtype generalized myasthenia gravis

BackgroundAn accurate prediction for prognosis can help in guiding the therapeutic options and optimizing the trial design for generalized myasthenia gravis (gMG). We aimed to develop and validate a predictive nomogram to assess the short-term outcome in patients with the anti-acetylcholine receptor (AChR) subtype gMG.MethodsWe retrospectively reviewed 165 patients with AChR subtype gMG who were immunotherapy naive at the first visit from five tertiary centers in China. The short-term clinical outcome is defined as the achievement of minimal symptom expression (MSE) at 12 months. Of them, 120 gMG patients from Huashan Hospital were enrolled to form a derivation cohort (n=96) and a temporal validation cohort (n=24) for the nomogram. Then, this nomogram was externally validated using 45 immunotherapy naive AChR subtype gMG from the other four hospitals. Multivariate logistic regression was used to screen independent factors and construct the nomogram.ResultsMSE was achieved in 70 (72.9%), 20 (83.3%), and 33 (73.3%) patients in the training, temporal validation, and external validation cohort, respectively. The duration <= 12 months (p=0.021), ocular score <= 2 (p=0.006), QMG score>13 (p=0.008), and gross motor score <= 9 (p=0.006) were statistically associated with MSE in AChR subtype gMG. The nomogram has good performance in predicting MSE as the concordance indexes are 0.81 (95% CI, 0.72-0.90) in the development cohort, 0.944 (95% CI, 0.83-1.00) in the temporal validation cohort, and 0.773 (95% CI, 0.63-0.92) in the external validation cohort.ConclusionThe nomogram achieved an optimal prediction of MSE in AChR subtype gMG patients using the baseline clinical characters.

Automated summary

The study aimed to develop and validate a predictive nomogram for assessing short-term outcomes in patients with anti-acetylcholine receptor subtype gMG, showing good performance in predicting minimal symptom expression based on baseline clinical characteristics.