Late-onset Compared to Adult-onset Multiple Sclerosis: Differences in Clinical and Cognitive Profiles and Impact of Sex
Nicolò Tedone1, Paolo Preziosa2, Damiano Mistri1, Matteo Azzimonti2, Massimo Filippi3, Maria Rocca2
1Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 2Neuroimaging Research Unit, Division of Neuroscience; and Neurology Unit, 3Neuroimaging Research Unit, Division of Neuroscience; Neurology Unit; Neurorehabilitation Unit; and Neurophysiology Service, IRCCS San Raffaele Scientific Institute; and Vita-Salute San Raffaele University
Objective:
To compare clinical and cognitive characteristics between late-onset (LO) multiple sclerosis (MS) and adult-onset (AO) MS and investigate sex-related differences.
Background:
The proportion of patients with MS onset occurring after 45 years of age (i.e., LOMS) is increasing. Although previous studies suggested different clinical features between LOMS and AOMS, a comprehensive evaluation including also cognitive profiles and sex influence has not been fully undertaken yet.
Design/Methods:
Sixty-one LOMS patients (females=31) and 122 disease duration- and sex-matched AOMS patients (females=62) underwent comprehensive neurological and neuropsychological evaluations. Differences in clinical (type of onset, Expanded Disability Status Scale [EDSS], 9-hole Peg Test, and Timed 25-Foot Walk test [T25FWT]) and neuropsychological features (performance and frequency of impairment of global cognitive functions and of specific domains, presence and severity of fatigue and depression) were explored, considering also sex.
Results:
Compared to AOMS, LOMS patients exhibited higher prevalence of motor onset, of reaching EDSS 3.0 milestone, and worse T25FWT (p≤0.036). LOMS patients were also more frequently cognitively impaired, with significantly worse performance in visual memory and higher prevalence of attention and verbal fluency impairment (p≤0.034). LOMS males had a more frequent motor onset, significantly worse T25FWT, higher prevalence of more cognitive impairment, and higher prevalence of depression compared to AOMS males (p≤0.026). LOMS females performed significantly worse in visual memory, but had significantly lower fatigue compared to AOMS females (p≤0.025). Compared to AOMS females, males showed worse T25FWT and worse performance and higher prevalence of impairment in verbal memory and attention (p≤0.042). Compared to LOMS females, males showed worse performance and higher prevalence of impairment in attention, and higher frequency of depression (p≤0.035). 
Conclusions:
LOMS patients exhibited worse clinical and cognitive features compared to AOMS patients, regardless from sex. Male patients showed more severe clinical and cognitive impairment in both AOMS and LOMS.
10.1212/WNL.0000000000205034