title: Relationship Between Age, Gender, and Race in Patients Presenting With Myasthenia Gravis With Only Ocular Manifestations.
abstract: BACKGROUND
  The demographic associations among patients presenting with myasthenia gravis with only ocular manifestations (OMG) is not clear.
  
  
  METHODS
  In this 5-center case series, we collected the race, gender, and age at diagnosis of patients diagnosed with myasthenia gravis who had no signs or symptoms of generalized myasthenia gravis (GMG). An a priori sample size calculation determined that 140 patients were required to accept that there was a ≤10-year difference in mean age (equivalence testing: power 90%, α = 0.05). Robust Bayesian analysis and linear regression were applied to evaluate whether age differed by gender or race.
  
  
  RESULTS
  Of 433 patients included, 258 (60%) were men. Mean age among men was 57 years (SD = 19) and 52 years (SD = 21) among women. The 95% credible interval (CI) (Bayesian equivalent of confidence interval) was 0.8-8.7 years for mean age, and there was a 99.6% probability that the mean difference in age between sexes was <10 years. Race was documented in 376 (68 [18%] non-Caucasian). Caucasians were 17.3 years older than non-Caucasians at diagnosis (95% CI, 12.2-22.3 y; P < 0.001) controlling for gender. There was no additive interaction of gender and race (P = 0.74). There was a bimodal distribution for women peaking around 30 and 60 years. Men had a left skewed unimodal age distribution peaking at age 70.
  
  
  CONCLUSIONS
  The distribution of age at presentation in patients with OMG is different between men and women, similar to GMG. Non-Caucasian patients tend to develop OMG at a younger age.
authors.affiliation: Departments of Ophthalmology (JHP, BBB), Pediatrics (JHP), and Neurology (BBB), Emory University, Atlanta, Georgia; Department of Ophthalmology and Visual Neurosciences (EB, MSL), University of Minnesota, Minneapolis, Minnesota; New York Eye and Ear Infirmary and INN at Roosevelt Hospital (MJK), New York, New York; Department of Neuro-ophthalmology (MJK), New York Eye and Ear Infirmary of Mount Sinai, New York, New York; Department of Neurology (FZ), Medical University of Vienna, Vienna, Austria; Department of Ophthalmology (TJW), University of Kansas Medical Center, Kansas City, Kansas; and Department of Epidemiology (B.B.B.), Rollins School of Public Health and Laney Graduate School, Emory University, Atlanta, Georgia.
authors.forename: Jason H
authors.initials: JH
authors.lastname: Peragallo
authors.forename: Elena
authors.initials: E
authors.lastname: Bitrian
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Kupersmith
authors.forename: Fritz
authors.initials: F
authors.lastname: Zimprich
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Whittaker
authors.forename: Michael S
authors.initials: MS
authors.lastname: Lee
authors.forename: Beau B
authors.initials: BB
authors.lastname: Bruce
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D018450:Disease Progression; D005006:Ethnicity; D005128:Eye Diseases / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000175:diagnosis / Q000453:epidemiology*; D009801:Oculomotor Muscles / Q000473:pathology; D012189:Retrospective Studies; D017678:Sex Distribution; D014481:United States / Q000453:epidemiology