AQP4-IgG-positive neuromyelitis optica spectrum disorder with late onset in Mexico

Sex ratio and age of onset in AQP4 antibody-associated NMOSD: a review and meta-analysis

BACKGROUND

Aquaporin-4 (AQP4) antibody-associated neuromyelitis optica spectrum disorder (NMOSD) is an antibody-mediated inflammatory disease of the central nervous system. We have undertaken a systematic review and meta-analysis to ascertain the sex ratio and mean age of onset for AQP4 antibody associated NMOSD. We have also explored factors that impact on these demographic data.

METHODS

A systematic search of databases was conducted according to the PRISMA guidelines. Articles reporting sex distribution and age of onset for AQP4 antibody-associated NMSOD were reviewed. An initially inclusive approach involving exploration with regression meta-analysis was followed by an analysis of just AQP4 antibody positive cases.

RESULTS

A total of 528 articles were screened to yield 89 articles covering 19,415 individuals from 88 population samples. The female:male sex ratio was significantly influenced by the proportion of AQP4 antibody positive cases in the samples studied (p < 0.001). For AQP4 antibody-positive cases the overall estimate of the sex ratio was 8.89 (95% CI 7.78-10.15). For paediatric populations the estimate was 5.68 (95% CI 4.01-8.03) and for late-onset cases, it was 5.48 (95% CI 4.10-7.33). The mean age of onset was significantly associated with the mean life expectancy of the population sampled (p < 0.001). The mean age of onset for AQP4 antibody-positive cases in long-lived populations was 41.7 years versus 33.3 years in the remainder.

CONCLUSIONS

The female:male sex ratio and the mean age of onset of AQP4 antibody-associated NMOSD are significantly higher than MS. The sex ratio increases with the proportion of cases that are positive for AQP4 antibodies and the mean age of onset increases with population life expectancy.

Clinical characteristics of late-onset neuromyelitis optica spectrum disorder

BACKGROUND

Anti-aquaporin-4 (AQP-4) immunoglobulin G (IgG) is a major autoimmune antibody that contributes to the pathogenesis of neuromyelitis optica spectrum disorder (NMOSD). NMOSD often presents as disability, severe sensory impairment, and sleep disorders, which can cause anxiety and depression and further affect the quality of life. The age of onset is a key factor influencing the prognosis of NMOSD. However, this result was based on studies involving only anti-aquaporin-4 (AQP4) immunoglobulin G (IgG)-seropositive NMOSD patients or studies using the 2006 NMOSD diagnosis criteria. Therefore, further study of the age of onset of NMOSD is valuable. This study aimed to describe the clinical and magnetic resonance imaging (MRI) differences between early-onset neuromyelitis optica spectrum disorder (EO-NMOSD) and late-onset (LO)-NMOSD patients.

METHODS

Fifty patients were enrolled, their anti-AQP4-IgG titers were measured, and brain and spinal cord MRIs were obtained. Additionally, several questionnaires related to disease severity, anxiety, depression, cognition, sleep, pain, and fatigue were collected.

RESULTS

Higher AQP4-IgG seropositivity, higher AQP4-IgG titer, frequency of thoracic myelitis, and white matter hyperintensities (WMH), as well as greater severity of disability, greater severity of sleep disorders, higher anxiety, poorer cognitive function, and higher clinical dementia rating (CDR)-community affairs scores were observed in late-onset (LO)-NMOSD patients than those in early-onset (EO)-NMOSD. AQP4-IgG titer positively correlated with age, annual relapse rate, Expanded Disability Status Scale (EDSS) sensory scores, Activity of Daily Living Scale (ADL) scores, and Pittsburgh Sleep Quality Index (PSQI) scores. The EDSS-sensory scores positively correlated with age, relapse time, Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, PSQI, ADL, and CDR. WMH was positively correlated with age, EDSS-sensory scores, PSQI scores, and CDR scores and negatively correlated with the California Verbal Learning Test scores.

CONCLUSION

LO-NMOSD patients have worse prognoses than those of EO-NMOSD patients. Higher AQP4-IgG titers, more WMHs, thoracic myelitis, and severe sensory symptoms are associated with cognition, depression, anxiety, and sleep disorders.

Late-onset neuromyelitis optica spectrum disorder: A case series from Iran

INTRODUCTION

Neuromyelitis optica spectrum disorder (NMOSD) is a disabling autoimmune disease of the central nervous system that can start at ages of 50 or more, when it is called late-onset NMOSD (LO-NMOSD). Data on this disorder are sparse. In this cross-sectional study, patient characteristics of the disease were studied. LO-NMOSD patients of a tertiary center in Tehran were studied from 2016 to 2020.

CASE REPORTS

Eight patients were identified, half of whom were men. The diagnostic delay was from no time-lapse to three years (mean: 0.62, SD: 1.06), which was significantly shorter than in early-onset patients. Seven patients (87.5%) tested positive for AQP4-IgG which was significantly higher compared to early-onset patients (p-value=0.01). Four patients (50%) had both transverse myelitis and optic neuritis as presenting symptoms, while three (38%) had just myelitis and only one (12%) had optic neuritis.

CONCLUSION

There is discrepancy regarding different aspects of LO-NMOSD. Further studies are needed to clarify the subject in order to enhance diagnosis and treatment.

An Abnormally High Neutrophil-to-Lymphocyte Ratio Is Not an Independent Outcome Predictor in AQP4-IgG-Positive NMOSD

Background

The neutrophil-to-lymphocyte ratio (NLR) has been investigated in many autoimmune conditions as a biomarker of inflammation and/or disease activity. The role of NLR in AQP4-IgG-positive neuromyelitis optica spectrum disorders (NMOSD) is far from clear. In this study, NLR was evaluated in patients with AQP4-IgG-positive NMOSD at disease onset and its prognostic impact was subsequently assessed.

Methods

In this multicenter study, we retrospectively included all recent/newly diagnosed treatment-naïve patients with AQP4-IgG-positive NMOSD (n=90) from three different countries in Latin America (LATAM): Argentina, Ecuador, and Mexico. NLR was compared between AQP4-IgG-positive NMOSD and healthy controls (HC, n = 365). Demographic, clinical, paraclinical (including imaging), and prognostic data at 12 and 24 months were also evaluated. Multivariate regression analysis was used to describe and identify independent associations between the log-transformed NLR and clinical (relapses and EDSS) and imaging (new/enlarging and/or contrast-enhancing MRI lesions) outcomes.

Results

NLR was higher in NMOSD patients during the first attack compared with HC (2.9 ± 1.6 vs 1.8 ± 0.6; p<0.0001). Regardless of immunosuppressant’s initiation at disease onset, NLR remained higher in NMOSD patients at 12 (2.8 ± 1.3; p<0.0001) and 24 (3.1 ± 1.6; p<0.0001) months. No association was found at 12 and 24 months between the log-transformed NLR and the presence of relapses, new/enlarging and/or contrast-enhancing MRI lesions, and/or physical disability.

Conclusions

In this cohort of LATAM patients with AQP4-IgG-positive NMOSD, NLR was abnormally high in attacks but also during follow-up. However, a high NLR was not an independent predictor of clinical or imaging outcomes in our models.