1479: Association of Neuromyelitis Optica and Systemic Lupus Erythematosus: Analysis of National Inpatient Sample 

Faria Sami and Shilpa Arora, John H. Stroger, Jr. Hospital of Cook County, Chicago, IL

Background/Purpose: Neuromyelitis Optica (NMO), also known as Devic's disease, is a rare inflammatory demyelinating disorder causing myelitis and optic neuritis. While there have been reports of autoimmune diseases associated with NMO, especially Systemic Lupus erythematosus (SLE), a formal association between the two is not established. We aimed to investigate the occurrence of NMO in SLE patients and study the characteristics and outcomes of NMO and SLE hospitalizations utilizing the national inpatient sample (NIS) database.

Methods: The NIS database from 2016 to 2019 was used to extract data. Hospitalizations with the principal diagnosis of NMO with a secondary diagnosis of SLE were searched. Only adult patients above the age of 18 years were included. We studied and compared the characteristics and outcomes of SLE hospitalizations with and without NMO and performed regression analyses for statistical analysis. We also calculated the risk of NMO in SLE amongst all adult hospitalizations.

Results: There was a total of 6,965 adult hospitalizations with the principal discharge diagnosis of NMO. Among all SLE hospitalizations, 415 (0.05%) had the principal diagnosis of NMO. Patient characteristics and demographics of SLE patients with and without NMO are depicted in Table 1. SLE patients with NMO were younger in comparison to those without NMO (mean age 44.20 vs 52.51, P value < 0.001) and were more likely to be of African American (55.42% vs 30.21%, P value < 0.001) and Asian ethnicity (6.02% vs 2.36%, P value 0.04). These patients were more likely to have Medicaid or private insurance and were more often admitted to large bed size hospitals. None of the patients with SLE and NMO died. SLE and NMO patients had a longer length of stay in comparison to SLE patients without NMO (9.94 vs 5.45 days, P value < 0.001) as well as higher total charges (Table 2). The odds of NMO in SLE amongst all adult hospitalizations was 10.58 (P-value < 0.001).

Conclusion: SLE patients had a 10-fold higher risk of being hospitalized with NMO in comparison to the general population. SLE patients with NMO were more likely to be younger and of African American and Asian ethnicity. NMO did not impact mortality in SLE hospitalizations but increased the health care economic burden.
Table 1: Demographics and characteristics of SLE hospitalizations with and without NMO

Table 2: Outcomes of SLE hospitalizations with and without NMO
Disclosures: F. Sami, None; S. Arora, None.