RESUMO
IMPORTANCE: The American Academy of Neurology Axon Registry® provides real-world data for patients with multiple sclerosis and neuro-myelitis optica. However, some data are incomplete (e.g. demographics) and some relevant outcomes are not systematically captured in neurology documentation (e.g. visual acuity). The American Academy of Ophthalmology IRIS® Registry (Intelligent Research in Sight) contains demographic and visual function data that may complement Axon Registry-derived data to enhance understanding of real-world visual outcomes in neurological disease. OBJECTIVE: To combine Axon Registry and IRIS Registry data to reduce missingness of demographic information and characterize visual outcomes in patients with multiple sclerosis and neuro-myelitis optica. DESIGN: Cross-sectional study. SETTING: Outpatient neurology and ophthalmology clinical practices. PARTICIPANTS: Patients participating in both registries between January 1, 2014 through December 10, 2021 were included if they had repeat ICD-9/10 codes for with multiple sclerosis or neuro-myelitis optica in the Axon registry. EXPOSURE: Diagnosis (multiple sclerosis or neuro-myelitis optica). MAIN OUTCOME AND MEASURE: Age, sex, race and ethnicity were assessed in the individual registries and classified as conflicting, missing, or not missing in the combined data set. The IRIS Registry contributed visual acuity data. RESULTS: Among 60,316 patients with multiple sclerosis and 1,068 patients with neuro-myelitis optica in the Axon Registry, 14,085 and 252 had temporal overlap in the IRIS Registry. Combining data reduced missing or conflicting data for race and ethnicity by 15-19 % (absolute reduction, all p ≤ 0.0005), but not age (p = 1.0) or gender (p = 0.08). 10,907 patients with MS and 142 with NMO had visual acuity data in the IRIS Registry. Visual acuity averaged between eyes was worse in patients with NMO after adjusting for age and gender (0.17 logMAR, 95 %CI 0.12,0.21, p < 0.0005). CONCLUSION AND RELEVANCE: Using data from two registries reduced missing data for race and ethnicity and enabled examination of outcomes captured in the IRIS Registry for conditions that are diagnosed more frequently in the Axon Registry, demonstrating the utility of a multi-registry analysis.