Relapse-onset MS patients have a substantially reduced risk of contrast-enhancing lesions or new T2 lesions after they reach age 50 years, according to a longitudinal analysis of the Amsterdam MS cohort study (Coerver et al. Eur J Neurol 2023;30:2385-2392).

The cohort included 1063 MS patients; mean age was 34.9 years and 83.4% were untreated at study enrolment. Older age was associated with a lower risk of contrast-enhancing lesions. The odds ratio was 0.64 for age 40-50 vs. <40 years group; and 0.060 for the >50 years vs. <40 years group.

During the median 6.1-year follow-up, 87.9% of younger patients had any MRI activity compared to 64.4% of those aged >50 years. The proportion of patients with contrast-enhancing lesions was 61.2% vs. 37.0% for the two age groups, respectively. There was also a 68% lower risk of new T2 lesions in patients aged >50 years vs. <40 years during follow-up.

The authors suggested that less frequent MRIs in patients older than 50 years may be appropriate due to the lower risk of inflammatory disease activity with aging. They also noted that a less aggressive treatment approach may be preferred as patients get older due to the greater risk of adverse effects and the declining benefit of therapy.

A similar finding was reported by the Amsterdam group in collaboration with the University of Calgary (Koch et al. J Neurol 2020;267:2619-2624). In that cohort of patients with CIS/MS (N=1543), the risk of contrast-enhancing lesions substantially declined with aging. Age was the most important factor associated with enhancing lesions; patient sex, disease course and DMT were not associated with contrast enhancement.

A separate analysis by the same group of four clinical trials of RMS (Combi-Rx), SPMS (ASCEND) and PMS (PROMISE, INFORMS) also showed that the declining risk of contrast-enhancing lesions with aging was evident across the spectrum of disease courses (Koch et al. Neurology 2021;97:e1334-1342).