The strong visual disability predictors in neuromyelitis optica spectrum disorder include seropositivity for AQP4-IgG, optic neuritis at the first attack, and older age at onset. High-effect immunosuppression at an early stage is required for high-risk patients.
Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disorder involving the central nervous system (CNS), resulting in transverse myelitis and optic neuritis. NMOSD attacks can culminate in severe visual disability as the disease progresses.
This study retrospectively analyzed the medical records of patients diagnosed with NMOSD to develop prognostic models for the risk of visual disability in 1, 3, and 5 years. The study generated nomograms for predicting visual disability in NMOSD patients, concluding that high-risk individuals require active therapeutic strategies to prevent unfavorable disease outcomes. The study findings are published in the journal Frontiers in Immunology.
Baseline Characteristics of the Study Participants
The study included a total of 640 NMOSD patients. The study population was predominantly female, and the mean age was estimated to be 38 ± 14 years. During the follow-up period, 452 patients received maintenance immunosuppression therapy (IST), and 188 patients were not administered maintenance therapy, the median duration of which was estimated to be 68 months.
Selection and Development of Predictor Model
A reliable estimation of the average risk of visual disability in NMOSD patients was supported by the estimation of average risk, which included 14 candidate variables and 11.5 events per variable. NMOSD patients with older age at the time of disease onset were found to be at a higher risk of visual disability. The risk of visual disability was significantly higher in seropositive compared to seronegative NMOSD patients.
The risk decreased in patients who received maintenance IST; however, higher annual relapse rate and prior severe attacks before the administration of IST present as risk factors. Prediction model 1 (Lasso) included the onset of optic neuritis, no IST administration, higher annualized relapse rate before IST, and initial severe attack. In contrast, the additional predictors identified by model 2 (Cox regression) included seropositivity for AQP4-IgG, male gender, and age at onset.
Validation for Visual Disability Prediction Models
After adjusting for the over-optimism in the two models developed in this study, model 1 exhibited slightly better discrimination during the initial 2 years. In contrast, the discrimination was superior during the last 3 years when model 2 was utilized. Hence, the study demonstrated that model 2 has a better predicting ability for long-term outcomes. The calibration curves indicate a good agreement between the actual and predicted probability of visual disability in NMOSD patients in this study.
The study concluded that the strong visual disability predictors in NMOSD patients included seropositivity for AQP4-IgG, optic neuritis at the first attack, and older age at the time of onset.
Luo, W., Kong, L., Chen, H., Wang, X., Du, Q., Shi, Z., & Zhou, H. (2023). Visual disability in neuromyelitis optica spectrum disorders: prognostic prediction models. Frontiers in Immunology, 14. https://doi.org/10.3389/fimmu.2023.1209323