Backgroud: Neuromyelitis optica (NMO) is an autoimmune inflammatory disorder, which
is characterized by severe attacks of optic neuritis and myelitis. Antibodies (Ab) to aquaporin-4
(AQP4) (or NMO-IgG) as a serological biomarker of NMO have been widespread used. Nevertheless,
some NMO patients remain seronegative for AQP4-Ab and/or have no detected optic nerve
involvement. In addition, no consensus exists on the association between AQP4-Ab serostatus and
visual outcome in NMO. To drive a more precise estimate of this postulated relationship, a metaanalysis
was performed based on existing relevant studies.
Methods: Studies were searched by PubMed and MEDLINE up to March 2016. Study quality was
assessed, and meta-analysis was conducted using the RevMan 5.1. Odds ratios with 95% confidence
interval were calculated and funnel plot was applied to assess the potential publication bias.
Results: In a total of 1288 relevant studies, 18 studies satisfied the eligibility criteria and were included
in the systemic review. Only 9 studies appeared eligible for the meta-analysis, together including
624 AQP4-Ab-positive and 119 AQP4-Ab-negative NMO patients. The results revealed
associations between AQP4-Ab seropositivity and visual impairment in NMO (OR, 3.16; 95% CI,
1.09, 9.19; P = 0.03). The results of subgroup analyses based on different methods of AQP-4 detection
also showed significantly differences between AQP4-Ab seropositivity and visual impairment in
NMO, especially in CBA subgroup.
Conclusion: This meta-analysis indicates that AQP4-Ab serostatus has the positive with poor visual
outcome in NMO.