First clinical inflammatory demyelinating events of the central nervous system in a population aged over 70 years: A multicentre study.

Background: Few data are available regarding patients with very late-onset inflammatory demyelinating events. (VLO-IDE).

Objectives: The aim of this study was to describe the clinical, biological, and radiological characteristics and aetiological diagnosis of very late first inflammatory demyelinating events of the central nervous system.

Methods: We conducted a national descriptive retrospective multicentre study on a case series of patients aged >70 years at the time of VLO-IDE. Patients were recruited from a national call on behalf of the 'Société Francophone de la Sclérose en Plaques' (French Multiple Sclerosis Society).

Results: Twenty-five patients were referred (F:M sex ratio 2.1:1). The most frequent clinical impairment was a spinal cord deficit (23/25), usually severe (disability score, median EDSS 4.5 [2-9.5]). Spinal cord lesions were usually extensive, spanning at least three segments (11/25), and large brain lesions were also observed (lesions >20 mm in 6/25). The final aetiological diagnoses comprised multiple sclerosis (9/25), neuromyelitis optica spectrum disorders (7/25), neurosystemic lupus erythematosus (2/25), transverse myelitis without aetiological diagnosis (6/25) and optic neuritis (1/25).

Conclusions: This study highlights a particular phenotype of first clinical inflammatory demyelinating events in predominantly female patients aged >70 years who have severe motor impairment with common longitudinal extensive myelitis and large and common very active radiological inflammatory lesions. Neuromyelitis optica spectrum disorders seem overrepresented.