title: Distinctive characteristics of early-onset and late-onset neuromyelitis optica spectrum disorders.
abstract: OBJECTIVE
  Little is known about patients with neuromyelitis optica spectrum disorders (NMOSD) as defined by onset age. This study aimed to analyze the different demographic, clinical, laboratory, and magnetic resonance imaging (MRI) characteristics in early-onset (≤50 years) NMOSD (EONMOSD) and late-onset (>50 years) NMOSD (LONMOSD).
  
  
  METHODS
  We enrolled 142 patients with NMOSD from Tianjin Medical University General Hospital, Tianjin, China, and categorized them into two groups according to the age of onset: EONMOSD and LONMOSD. Demographic, clinical, laboratory, and MRI characteristics were collected and compared between the two groups. Serum aquaporin-4 (AQP4) antibody levels were determined by cell-based assay and fluorescence immunoprecipitation assays.
  
  
  RESULTS
  Among the patients studied, 83 had early onset (≤50 years) and 59 had late onset (>50 years) of NMOSD. As compared with LONMOSD, EONMOSD patients had more severe visual disability according to functional scores in clinical parameters, significantly lower C3 and C4 serum levels, more frequent cervical lesions, and more lesions around the fourth ventricle, but fewer lesions in hemispheric white matter. LONMOSD patients suffered more motor and sensory disability than EONMOSD patients.
  
  
  CONCLUSIONS
  In NMOSD, the clinical, laboratory, and MRI features differ according to age of onset, suggesting that differences in pathogenesis and treatment should be further investigated.
authors: a Department of Neurology, Tianjin Neurological Institute , Tianjin Medical University General Hospital , Tianjin , China.
authors: Lin-Jie
authors: LJ
authors: Zhang
authors: b Department of Medicine , Shijiazhuang Medical College , Hebei , China.
authors: Li-Na
authors: LN
authors: Yang
authors: a Department of Neurology, Tianjin Neurological Institute , Tianjin Medical University General Hospital , Tianjin , China.
authors: Ting
authors: T
authors: Li
authors: a Department of Neurology, Tianjin Neurological Institute , Tianjin Medical University General Hospital , Tianjin , China.
authors: Jing
authors: J
authors: Wang
authors: a Department of Neurology, Tianjin Neurological Institute , Tianjin Medical University General Hospital , Tianjin , China.
authors: Yuan
authors: Y
authors: Qi
authors: a Department of Neurology, Tianjin Neurological Institute , Tianjin Medical University General Hospital , Tianjin , China.
authors: Da-Qi
authors: DQ
authors: Zhang
authors: a Department of Neurology, Tianjin Neurological Institute , Tianjin Medical University General Hospital , Tianjin , China.
authors: Chun-Sheng
authors: CS
authors: Yang
authors: a Department of Neurology, Tianjin Neurological Institute , Tianjin Medical University General Hospital , Tianjin , China.
authors: Li
authors: L
authors: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000097:blood; D051401:Aquaporin 4 / Q000276:immunology; D004185:Disability Evaluation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000097:blood / Q000453:epidemiology*; D055815:Young Adult
chemical_list: C496030:AQP4 protein, human; D000906:Antibodies; D051401:Aquaporin 4
keywords: Age; aquaporin-4; neuromyelitis optica spectrum disorders