“Time plays for you” – this is a common statement when therapy decisions are pending for older MS patients. I probably have to define what older MS patients are first. Immunologically speaking, these are MS patients who have passed the age of 55. During this period there is a slow “deterioration” of the immune system – which we refer to as immunosenescence (from Latin senescere = getting old). The negative impact of the aging of the immune system is that old people become more susceptible to infectious diseases and the risk of disease and death from pathogens increases with age. This altered functionality of the immune system in old age is associated with diverse and complex changes in innate and acquired immunity, some of which are not yet fully understood. For example, an age-related decreased number of white blood cells can be detected, a decreased maturation of B cells with reduced production of antibodies, and a shift in the cytokine profile – i.e., the messenger substances that act pro-inflammatory or anti-inflammatory.
This fundamentally not great development of the immune system in old age, however, contributes to the fact that the “drive” of such diseases can significantly decrease in old age in older people with autoimmune diseases like MS. Now, one should not rely on this “naively”, because the process is overall not yet well understood and there are of course always individual differences. Nevertheless, the phenomenon of immunosenescence can be included in the considerations when advising patients.
What does this look like in practice? I’m not a fan of discontinuing immunotherapies when stable – because then these therapies are doing exactly what you want to achieve. However, in an MS patient who has passed the age of 55, a trial discontinuation (under regular observation) is justifiable against the background of the expected immunosenescence in the event of disease stability. Another example would be a patient who has repeatedly decided against continuous immunotherapy. If he has passed the age of 50, like most patients without therapy, a mobility disorder has developed that is slowly progressing. He hasn’t had attacks for years, the MRI shows no significant changes – so a classic secondary chronic progressive MS without activity. Here too, against the background of the natural aging of the immune system, it can be assumed that no extreme changes will occur anymore and immunoprophylaxis probably won’t have much benefit anymore.
The considerations regarding immunosenescence are rather general in nature. They are not insurance that there cannot still be significant increases in MS activity in old age, which also require medicinal action. Even though it is unusual, I sometimes have MS patients over 70 who still show inflammation activity. Therefore, the examples mentioned above can only be seen as individual cases. Nevertheless, I think that the aging of the immune system is an interesting phenomenon that should definitely be included in the consultation with patients.
