Objective: To estimate the incidence and prevalence of NMO in a

Ph.D. Student: Nasrin Asgari M.D.
Enrolment : 1 November 2008
Project Title : Epidemiological, clinical and immunological aspects of neuromyelitis optica (NMO)
Supervisors : Professor Kirsten Ohm Kyvik, M.D., Ph.D., MPM, Head of Institute for Regional
Health Services Research, University of Southern Denmark (SDU), Professor Trevor
Owens, Ph.D. Institute of Molecular Medicine,SDU, Professor Jørgen Frøkiær, M.D.
co-head of the consortium on aquaporins at University of Aarhus , Egon Stenager,
M.D. Head of The Multiple Sclerosis Clinic of Southern Jutland (Sønderborg, Vejle,
Esbjerg hospitals).
Collaborator: Søren Lillevang M.D., Ph.D., Department of Clinical Immunology Odense
University Hospital
: Institute of Regional Health Services Research
Abstract represents the epidemiological/clinical part of the project.
Background: Epidemiological studies have suggested ethnicity-based prevalence differences of
neuromyelitis optica (NMO). Limited knowledge still exists of the prevalence of NMO in
Caucasians (1).
Objective: To estimate the incidence and prevalence of NMO in a predominantly Caucasian
population, to describe the clinical presentations of NMO in this population.
Methods: Clinical data from patients with multiple sclerosis (MS), optic neuritis (ON), acute
transverse myelitis (TM) and NMO diagnosed 1998 - 2008 were obtained from the four Neurology
and three Ophthalmology Departments in The Region of Southern Denmark. The patient material
was cross-checked with information from The Danish National Patient Registry. Patients were
included based on: 1) one or more episodes of ON and/or TM and 2) an initial brain MRI that was
not diagnostic for MS. The Wingerchuck 2006 criteria(2) were used for NMO diagnosis. An
immunofluorescence assay was used to determine aquaporin-4 (AQP-4) antibodies. The diagnosis
of NMO was initially made clinically without knowledge of AQP4 antibody results and vice versa.
Results: 477 patients were evaluated, 163 with MS, TM and ON fulfilled the inclusion criteria, 42
(26.6%) qualified for the diagnosis of NMO 26/42 (62.0%) were AQP4 antibody positive. All
except one were Caucasians with a female:male ratio was 2.8: 1, mean age at onset was 35.6 years
(range 15–64 years). The clinical presentation was heterogeneous including TM, longitudinal
extensive TM, ON and brainstem syndromes. The yearly incidence rate of NMO in the population
was estimated at 0.4 per 105 person-years and the prevalence was 4.4 per 105.
Conclusions: An unexpectedly common occurrence of NMO was observed in a Caucasian
Reference List
(1) Asgari N, Owens T, Frokiaer J, Stenager E, Lillevang ST, Kyvik KO. Neuromyelitis optica (NMO) - an
autoimmune disease of the central nervous system (CNS). Acta Neurol Scand 2010 Sep 29.
(2) Wingerchuk DM, Lennon VA, Pittock SJ, Lucchinetti CF, Weinshenker BG. Revised diagnostic criteria for
neuromyelitis optica. Neurology 2006 May 23;66:1485-1489.
Keywords: Neuroscience, Clinical Research