The subject characteristics are shown in Table 1. The study population of 40,428 PwMS (Fig. 1) subsets into 70% PwMS < 55 (n = 28,313), 22.6% PwMS55-64 (n = 9120), and 7.4% PwMS ≥ 65 (n = 2995). The female/male ratio was comparable across the age groups. PwMS < 55 had a mean EDSS of 2.7 indicating no walking restriction, while the PwMS55-64 and PwMS ≥ 65 displayed a restricted walking range (mean EDSS 4.2 and 5.3, respectively). The frequency of individuals with a relapsing–remitting disease course declined across age groups (Table 1).

The rate of occupational invalidity was 17.2% in PwMS < 55 and 38.8% for PwMS55-64. The full employment rate was 45.3% for PwMS < 55 and 25.8% of PwMS55-64 (Table 1). In comparison, in the general population in Germany in 2022, 78.0% of persons from 18–55 and 67% of persons from 55–65 years were fully employed [12].

The need for walking assistance was more frequent among PwMS of older age: walking sticks were required by 13.7%, 30.4%, and 44.4% of PwMS < 55, PwMS55-64, and PwMS ≥ 65. Any wheelchair access (not necessarily permanent use) was documented for 9.2%, 22.0%, and 35.2% PwMS < 55, PwMS55-64, and PwMS ≥ 65, respectively.

The need for care and assistance for PwMS was higher in the older age groups. Care and support by family members was reported for 19.8% of the PwMS < 55, 33.6% for PwMS55-64, and 52.3% of the PwMS ≥ 65 (Table 1). In comparison, in the general population in Germany only 0.1–1.1% of persons below the age of 55 receive care and support by family members [12].

Disease symptom load was higher in older age groups, but patterns of symptoms were similar. Gait disorder, spasticity, ataxia, pain, bladder and bowel dysfunction, dysarthria and dysphagia were among the most frequently reported symptoms, were significantly more prevalent among the older age groups, and with the highest rates in PwMS ≥ 65 (Table 1).

Ocular motor dysfunction, sexual dysfunction, fatigue, cognitive impairment, and depression also showed higher rates in the older age groups, with an equal or even higher frequency in PwMS 55–64 as compared to PwMS ≥ 65. Epilepsy rates were significantly higher in PwMS ≥ 65.

With regards to treated symptoms, only 21.8% of sexual disorders, 32.9% of patients with fatigue and 32.1% of patients with cognitive deficits were reported to be treated across all age groups, with no detailed information on the treatment applied available.

The frequency of a relapse reported within the last year, registered at date of presentation, was higher in PwMS < 55 with 13%, as compared with 7% or 8% for PwMS55-64, and PwMS ≥ 65, respectively.

A cranial MRI within the last year was reported to be conducted more frequently in the younger age groups, with 49.3%, 40.6%, and 31.3% of PwMS < 55, PwMS55-64, and PwMS ≥ 65, respectively.

In those, MRI activity, defined by new or enlarging T2 lesions and/or GD enhancing lesions in comparison to the preceding scan, was more frequently noted in PwMS < 55 with 23.8%, as compared with a frequency of 15.1% both in PwMS55-64 and PwMS ≥ 65 (Table 1).

Data on comorbidities were limited, recorded for only 13.2% (5317/40428) of the total registry population. Availability of comorbidity data was similar across the age groups with 13.3% (3764/28313) for PwMS < 55, 12.7% (1160/9120) for PwMS55-64, and 13.1% (393/2995) for PwMS ≥ 65.

Vascular risk factors, such as hypertension and diabetes, were more often reported in PwMS ≥ 65: hypertension with 38.4% as compared with 24.1% in PwMS55-64 and 9.2% in PwMS < 55, and type II diabetes in 1.8% as compared with below 1% in the younger age groups.

Infections were also more frequently reported in older age groups: pneumonia in 1.3% of PwMS ≥ 65, 1.4% of PwMS55-64, and 0.7% of PwMS < 55; urinary tract infections in 5.1% of PwMS ≥ 65 vs. 4.2% of PwMS55-64 and 2.2% of PwMS < 55, and herpes simplex viral infections in 7.6% of PwMS ≥ 65 vs. 5.0% of PwMS55-64, and 3.2% in PwMS < 55 (Table 2).

Detailed DMT data was available for a subgroup of registered patients (Table 3). At time of the last registry entry, for 70.6% of these PwMS current DMT use was reported, with 76.7%, 60.9%, and 42.6% for PwMS < 55, PwMS55-64, and PwMS ≥ 65, respectively. Moderate efficacy DMT, including interferon beta variants, glatiramer acetate, dimethyl fumarate, diroximel fumarate or teriflunomide did not show a difference in the distribution between the age groups, with 45.9% of PwMS < 55, 47.5% of PwMS55-64, and 45.7% of PwMS ≥ 65.

Grouped higher efficacy drugs (monoclonal antibodies (alemtuzumab, natalizumab, ocrelizumab, rituximab, ofatumumab), purine analog (cladribine), sphingosine I-phosphate receptor modulators (fingolimod, ozanimod, ponesimod)) were more frequently recorded in the younger age groups, with 49.9%, 38.5%, and 25.4% for PwMS < 55, PwMS55-64, and PwMS ≥ 65, respectively.

Looking separately at single compounds, no significant differences were noted for the use of cladribine, ocrelizumab, and rituximab across age groups. Natalizumab, ofatumumab, fingolimod, and ozanimod were more frequently reported in the younger age groups. Siponimod, registered in the EU for active SPMS only, was more frequently used in the older age groups (Table 3).