University of California, San Fransisco
Neurology

Author Of 1 Presentation

Pediatric MS Oral Presentation

PS04.04 - Evidence for an interaction between ozone pollution and HLA-DRB1*15 alleles in pediatric multiple sclerosis

Abstract

Background

We previously reported a relationship between air pollutants and increased risk of pediatric MS (ped-MS). Environmental risk factor research in ped-MS offers the advantage of shorter duration between exposure and disease onset. Ozone, an air pollutant, is a major global health hazard thought to have a role in MS pathoetiology. Identifying gene-environment interactions advances the understanding of biological processes at play in MS susceptibility.

Objectives

We sought to examine the interaction between ozone pollution and DRB1*15 status as the main genetic variant associated with MS susceptibility.

Methods

Cases and controls enrolled in the Environmental and Genetic Risk Factors for Pediatric MS study of the US Network of Pediatric MS Centers were analysed. County-level modeled ozone data were acquired from the CDC’s Environmental Tracking Network air pollution database. Participants were assigned ozone values based on county of residence. Values were categorized into tertiles based on healthy controls. The association between ozone tertiles and having MS were assessed by logistic regression. Interaction between tertiles of ozone level and presence of DRB1*15 alleles on odds of ped-MS was evaluated. Models were adjusted for sex, race, ethnicity, age, second-hand smoke exposure, and mother’s education. Additive interaction was estimated using relative risk due to interaction (RERI) and attributable proportion of disease were calculated.

Results

355 ped-MS cases and 565 controls contributed to the analyses. Ozone levels were associated with MS with an odds ratio (OR) of 2.35 (95%CI 1.57–3.51) and 2.21 (95%CI 1.48–3.32) in the upper two tertiles, respectively, compared with the lowest tertile. DRB1 status was also independently associated with MS (OR 1.99; 95%CI 1.43–2.78). There was a significant additive interaction between ozone and DRB1, with a RERI of 2.74 (95%CI 0.50–4.98) and 2.43 (95%CI 0.36–4.5) in the upper two tertiles, respectively. Approximately 60% of the ped-MS risk in those with HLA-DRB1*15 haplotype and high ozone exposure was attributable to the interaction between these risk factors.

Conclusions

Our data revealed additive interaction between higher exposure to ozone and DRB1 alleles on ped-MS susceptibility. Further evaluation of additional genetic variants that might play a role in ozone-induced ped-MS is underway to provide mechanistic insight.

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Presenter Of 1 Presentation

Pediatric MS Oral Presentation

PS04.04 - Evidence for an interaction between ozone pollution and HLA-DRB1*15 alleles in pediatric multiple sclerosis

Abstract

Background

We previously reported a relationship between air pollutants and increased risk of pediatric MS (ped-MS). Environmental risk factor research in ped-MS offers the advantage of shorter duration between exposure and disease onset. Ozone, an air pollutant, is a major global health hazard thought to have a role in MS pathoetiology. Identifying gene-environment interactions advances the understanding of biological processes at play in MS susceptibility.

Objectives

We sought to examine the interaction between ozone pollution and DRB1*15 status as the main genetic variant associated with MS susceptibility.

Methods

Cases and controls enrolled in the Environmental and Genetic Risk Factors for Pediatric MS study of the US Network of Pediatric MS Centers were analysed. County-level modeled ozone data were acquired from the CDC’s Environmental Tracking Network air pollution database. Participants were assigned ozone values based on county of residence. Values were categorized into tertiles based on healthy controls. The association between ozone tertiles and having MS were assessed by logistic regression. Interaction between tertiles of ozone level and presence of DRB1*15 alleles on odds of ped-MS was evaluated. Models were adjusted for sex, race, ethnicity, age, second-hand smoke exposure, and mother’s education. Additive interaction was estimated using relative risk due to interaction (RERI) and attributable proportion of disease were calculated.

Results

355 ped-MS cases and 565 controls contributed to the analyses. Ozone levels were associated with MS with an odds ratio (OR) of 2.35 (95%CI 1.57–3.51) and 2.21 (95%CI 1.48–3.32) in the upper two tertiles, respectively, compared with the lowest tertile. DRB1 status was also independently associated with MS (OR 1.99; 95%CI 1.43–2.78). There was a significant additive interaction between ozone and DRB1, with a RERI of 2.74 (95%CI 0.50–4.98) and 2.43 (95%CI 0.36–4.5) in the upper two tertiles, respectively. Approximately 60% of the ped-MS risk in those with HLA-DRB1*15 haplotype and high ozone exposure was attributable to the interaction between these risk factors.

Conclusions

Our data revealed additive interaction between higher exposure to ozone and DRB1 alleles on ped-MS susceptibility. Further evaluation of additional genetic variants that might play a role in ozone-induced ped-MS is underway to provide mechanistic insight.

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Author Of 1 Presentation

Neuromyelitis Optica and Anti-MOG Disease Poster Presentation

P0696 - Characteristics of Myelin Oligodendrocyte Glycoprotein Antibody Positive Children with Demyelinating Disorders (ID 1565)

Speakers
Presentation Number
P0696
Presentation Topic
Neuromyelitis Optica and Anti-MOG Disease

Abstract

Background

Myelin oligodendrocyte glycoprotein (MOG) antibodies (ab) are detected in approximately 1/3 of children with demyelinating disease at onset; presentations commonly overlap with optic neuritis, neuromyelitis optica spectrum disorder (NMOSD) or acute disseminated encephalomyelitis. Serum MOG-ab titers have unclear relevance to disease course, and optimal treatment strategy is unknown.

Objectives

We aimed to characterize children with CNS demyelinating disorders who tested positive for MOG-ab. We also aimed to evaluate the relevance of serum MOG-ab titers for diagnosis, risk and severity of subsequent demyelinating events. Finally, we aimed to evaluate treatment strategies for MOG-ab positive children.

Methods

This retrospective study evaluated children with demyelinating disorders with onset before 18 years of age seen at the University of California, San Francisco who tested positive for MOG-ab (tested by live cell-based fluorescent activated cell sorting assay at Mayo Clinic) between October 2006-June 2020. Demographic information, clinical presentation at onset, MRI, CSF, brain biopsy, and treatment data were collected by chart review.

Results

Sixty children were included (mean onset age 8.2 years; 53% female; 72% white; 40% Hispanic or Latino). The most common clinical localization at onset included optic nerve (ON) (53%) and/or brainstem/cerebellum (42%). 83% of initial events were severe. Median EDSS assessed within 6 months of onset was 1.5 (range 0-4). 81% of initial brain MRIs had T2 bright lesions and 61% had gadolinium-enhancing lesions; T2 bright lesions were most commonly seen in subcortical areas (50%) and/or brainstem/cerebellum (33%). Oligoclonal bands were positive in 17% of initial CSF. 57% had initial serum MOG-ab titers ≥1:100 (median time from onset to first titer 15.4 months). Titers ≥1:320 were only observed within 2 months of an event (disease onset or relapse). While 38% had no relapses (mean follow-up 1.42 years), those who did had a median of 2 relapses (mean follow-up 3.83 years). The most commonly used treatments were interferon beta (28%) and rituximab (27%). Brain biopsy was performed in 2 patients and showed overt demyelination and prominent infiltration of monocyte lineage and polymorphonuclear cells.

Conclusions

The most common clinical onset localizations in MOG-ab positive children were ON and brainstem/cerebellum. Higher MOG-ab titers were only observed close to a clinical event.

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