Relative change rate of anti-acetylcholine receptor antibodies concentration Correlates with the recurrence of myasthenia gravis in AChR-Abs-positive patients

Abstract

Backgrounds

Myasthenia gravis (MG) is an autoimmune disease predominantly caused by anti-acetylcholine receptor antibodies (AChR-Abs). In this study, the relationship between MG relapse and AChR-Abs concentration were investigated.

Methods

We retrospectively reviewed the clinical records of 41 patients with AChR-Abs-positive MG. Data collected included age, sex, MG status within 12 months (untreated status, UTMG; recurrence status, RCMG), MG subgroups, QMGs, AChR-Abs concentration and treatments. The relative change rate (RCR) of AChR-Abs concentration was calculated as: RCR(%)=(AChR-Abs–AChR-Abs_UTMG)/AChR-Abs_UTMG/month*100. ROC curve analysis and binary logistic regression analyses were used to evaluate the association between these factors and MG recurrence.

Results

Within 12 months, 12 patients experienced a recurrence (RCMG). A weak correlation was observed between AChR-Abs level in UTMG and QMGs (r = 0.336, p = 0.032). MG subgroups, QMGs, AChR-Ab levels and RCR differed significantly between RCMG and non-RCMG group. Single factor ROC curves indicated that AChR-Abs concentration, RCR and MG subgroups were related to MG recurrence (AUC = 0.724, 0.736, 0.736). Combining with RCR and MG subgroups, the ROC yielded an AUC of 0.899, demonstrating high sensitivity and specificity.

Conclusion

RCR of AChR-Abs was correlated with MG progression, and repeated AChR-Abs measurements can assist in monitoring disease status and guiding therapeutic decision-making.