Excess weight, central adiposity and pro-inflammatory diet consumption in patients with neuromyelitis optica spectrum disorder

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.

The association between dietary inflammatory index and risk of neuromyelitis optica spectrum disorder: a case-control study

BACKGROUND AND AIM

Neuromyelitis optica spectrum disorder (NMOSD) is a severe and rare inflammatory disease affecting the central nervous system through optic neuritis and transverse myelitis. Present study aimed to investigate the association between dietary inflammatory index (DII) and risk of NMOSD.

METHODS

In this case-control study, 30 NMOSD cases and 90 aged matched healthy individuals were recruited. Habitual dietary intakes were assessed by a validated 168-item food frequency questionnaire to calculate the DII score. A multiple adjusted regression was used to determine the odd ratio (OR) of NMOSD across DII tertiles. The Residual method was applied to adjust the energy intake.

RESULTS

Participants in the top of DII tertile were more likely to have NMOSD in the crude model compared to those with the lowest one (OR: 4.18; 95%CI: 1.43-12.21). It was the case when multivariable confounders were considered in adjustment model I (OR: 3.98; 95%CI: 1.34-11.82) and II (OR: 4.43; 95%CI: 1.36-14.38), such that, individuals with a greater DII score had 3.98 and 4.43-time higher risk of NMOSD in model I and II, respectively.

CONCLUSION

The Present study suggests that greater adherence to a pro-inflammatory diet may be associated with an increased risk of NMOSD.

Clinical features and prognosis of Tibetan patients with neuromyelitis optica spectrum disorder are different from those of Han Chinese patients

We compared the prognosis of Tibetan and Han Chinese patients with neuromyelitis optica spectrum disorder (NMOSD). The Expanded Disability Status Scale (EDSS) score at each attack, response to immunosuppressive therapy, risk of first relapse, severe attack, visual disability, motor disability, and total risk of disability were compared between Tibetan and Han Chinese patients. Tibetan patients showed higher EDSS during acute attacks. Annualized relapse rate did not differ between groups. Risk of severe attack, visual disability, and total risk of disability were higher in Tibetan patients. Tibetan patients with NMOSD have a higher risk of poor prognosis than Han Chinese patients.

Initial BMI effects on clinical presentation and prognosis in neuromyelitis optica spectrum disorder

OBJECTIVE

To investigate the correlation among body mass index at onset, clinical features, and prognosis in patients with neuromyelitis optica spectrum disorder.

METHOD

This retrospective cohort studied patients with neuromyelitis optica spectrum disorder from January 2015 to January 2022, grouping them by body mass index at onset. Demographics and clinical records were reviewed. Anderson-Gill, Kaplan-Meier, and Cox models evaluated the body mass index's effect on relapse risk and long-term outcomes.

RESULTS

Of 246 patients with 799 neuromyelitis optica spectrum disorder attacks study, 36 patients had low, 133 had normal, 77 had high body mass index, with a mean onset age of 40 ± 13 years, and the population was 88% female. The medium follow-up time was 49 months; AQP4-IgG was found in 193 (78%) patients. Onset and relapse of area postrema syndrome were less frequent in patients with a normal body mass index. The annual relapse rate after immunosuppressive therapy was significantly lower in patients with a low body mass index. In the multivariable analysis, statistical correlation still existed between body mass index at onset and risk of relapse (HR = 1.03, 95% CI: 1.03-1.03, P < 0.001), risk of severe attack (HR = 0.92, 95% CI: 0.86-0.98, P = 0.013), risk of visual disability (HR = 0.9, 95% CI: 0.81-1, P = 0.047), and overall risk of disability (HR = 0.89, 95% CI: 0.82-0.98, P = 0.015) after adjusting various variables.

INTERPRETATION

Lower body mass index at onset was associated with less frequent relapse but poor prognosis.

The nutritional risk in patients with neuromyelitis optica spectrum disorder

BACKGROUND

The effect of nutrition on chronic autoimmune diseases is well known. This study is the first to assess the nutritional status of patients with neuromyelitis optica spectrum disorder (NMOSD) by administering the Mini Nutritional Assessment (MNA), to explore the impacts of nutrition on patients' quality of life and to identify the factors associated with the nutritional status of NMOSD patients.

METHODS

Our study enrolled 70 NMOSD patients and 66 healthy controls. The following data were assessed: demographic information, disease features, and composite evaluations of life status, including nutrition, sleep, anxiety/depression, fatigue, and quality of life. Then, statistical analysis was performed.

RESULTS

The MNA score of NMOSD patients was 20.4 ± 3.3, which was significantly lower than that of HCs (23.3 ± 2.5, P = 0.002), especially for the dimensions of global evaluation and anthropometric assessment. Nearly 85% of patients were at risk of malnutrition or had definite malnutrition. The total MNA score was positively correlated with the patient's quality of life (P<0.01). Lower MNA scores were correlated with gender (P = 0.02), longer disease duration (P<0.001), more severe anxiety (P = 0.004), more severe depression (P = 0.003), more severe sleep disturbances (P<0.001), and more severe fatigue (P = 0.01). Sleep disturbance was revealed to be a significant independent factor for the NMOSD patients' malnutritional risk (P = 0.001).

CONCLUSIONS

These results suggest that the risk of malnutrition is very high in NMOSD patients and that malnutrition is closely related to their quality of life. Malnutrition among NMOSD patients is caused by a combination of various physiological and psychological factors. A multifaceted and personalized intervention is required to improve the prognosis of NMOSD.

Oily fish and raw vegetable consumption can decrease the risk of AQP4-positive neuromyelitis optica spectrum disorders: a Mendelian-randomization study

Neuromyelitis optica spectrum disorders (NMOSD) are severe inflammatory disorders of the central nervous system targeting aquaporin-4 (AQP4). The risk factors for NMOSD remain to be determined, though they may be related to diet and nutrition. This study aimed to explore the possibility of a causal relationship between specific food intake and AQP4-positive NMOSD risk. The study followed a two-sample Mendelian randomization (MR) design. Genetic instruments and self-reported information on the intake of 29 types of food were obtained from a genome-wide association study (GWAS) on 445,779 UK Biobank participants. A total of 132 individuals with AQP4-positive NMOSD and 784 controls from this GWAS were included in our study. The associations were evaluated using inverse-variance-weighted meta-analysis, weighted-median analysis, and MR-Egger regression. A high consumption of oily fish and raw vegetables was associated with a decreased risk of AQP4-positive NMOSD (odds ratio [OR] = 1.78 × 10-16, 95% confidence interval [CI] = 2.60 × 10-25-1.22 × 10-7, p = 0.001; OR = 5.28 × 10-6, 95% CI = 4.67 × 10-11-0.598, p = 0.041, respectively). The results were consistent in the sensitivity analyses, and no evidence of directional pleiotropy was observed. Our study provides useful implications for the development of AQP4-positive NMOSD prevention strategies. Further research is needed to determine the exact causal relationship and mechanisms underlying the association between specific food intake and AQP4-positive NMOSD.

A national case-control study investigating demographic and environmental factors associated with NMOSD

BACKGROUND

Risk factors for aquaporin-4 (AQP4+) antibody neuromyelitis optica spectrum disorder (NMOSD) are not well-established.

OBJECTIVE

To investigate demographic and environmental factors associated with NMOSD using a validated questionnaire and case-control design.

METHODS

We enrolled patients with AQP4 + NMOSD through six Canadian Multiple Sclerosis Clinics. Participants completed the validated Environmental Risk Factors in Multiple Sclerosis Study (EnvIMS) questionnaire. Their responses were compared to those of 956 unaffected controls from the Canadian arm of EnvIMS. We calculated odds ratios (ORs) for the association between each variable and NMOSD using logistic regression and Firth's procedure for rare events.

RESULTS

In 122 participants (87.7% female) with NMOSD, odds of NMOSD in East Asian and Black participants were ⩾8 times that observed in White participants. Birthplace outside Canada was associated with an increased risk of NMOSD (OR = 5.5, 95% confidence interval (CI) = 3.6-8.3) as were concomitant autoimmune diseases (OR = 2.7, 95% CI = 1.4-5.0). No association was observed with reproductive history or age at menarche.

CONCLUSION

In this case-control study, risk of NMOSD in East Asian and Black versus White individuals was greater than that observed in many previous studies. Despite the preponderance of affected women, we did not observe any association with hormonal factors such as reproductive history or age at menarche.

Neuromyelitis optica spectrum disorders: a review with a focus on children and adolescents

Neuromyelitis optica spectrum disorder (NMOSD) is a rare and severe inflammatory disorder of the central nervous system (CNS). It is strongly associated with anti-aquaporin 4 antibodies (AQP4-IgG), and it mainly affects young women from non-white ethnicities. However, ∼ 5 to 10% of all cases have onset during childhood. Children and adolescents share the same clinical, radiologic, and laboratory presentation as adults. Thus, the same NMOSD diagnostic criteria are also applied to pediatric-onset patients, but data on NMOSD in this population is still scarce. In seronegative pediatric patients, there is a high frequency of the antibody against myelin oligodendrocyte glycoprotein (MOG-IgG) indicating another disease group, but the clinical distinction between these two diseases may be challenging. Three drugs (eculizumab, satralizumab, and inebilizumab) have been recently approved for the treatment of adult patients with AQP4-IgG-positive NMOSD. Only satralizumab has recruited adolescents in one of the two pivotal clinical trials. Additional clinical trials in pediatric NMOSD are urgently required to evaluate the safety and efficacy of these drugs in this population.