Fifteen-year longitudinal population-based study of very late-diagnosed multiple sclerosis: Epidemiological and...

The epidemiology of Multiple Sclerosis (MS) is evolving with increasing incidence and prevalence in older individuals, but data on very late-onset MS (VLOMS, ≥60 years) remains limited.

This study evaluates clinical features, disease progression, and long-term disability accumulation in VLOMS subjects from the Genoa MS cohort.

Among 530 incident MS cases (1998-2007), 38 (7.2 %) were diagnosed at ≥60 years. Data were collected and analyzed over a 15-year follow-up.

At diagnosis, the mean age was 65 years, with 22 females (57.9 %). 24 (63 %) had primary progressive MS (mean EDSS 3.8), and 14 (37 %) had relapsing-remitting MS (mean EDSS 3.0). Of the latter, 11 (79 %) converted to secondary progressive MS within a mean of 3.7 years. Overall, 35 (92 %) subjects reached EDSS 6 within a mean of 6.3 years. Number of comorbidities at diagnosis strongly related to the probability of being alive at last follow-up. 16 subjects received DMT, and only three remained on treatment at last follow-up. Mortality was 32 %, with a mean survival of 10 years from diagnosis.

VLOMS presents a severe disease course with rapid disability accumulation. Age at diagnosis remains the strongest predictor of disease progression, highlighting the need for tailored management strategies.