How Does Multiple Sclerosis Progress With Age?

The average age of MS diagnosis is 34 years old, and the symptoms of MS typically start between the ages of 20 and 40. However, in the US, multiple sclerosis is more prevalent in people aged 55-64 than in any other age group. This age group is more likely to see disease progression with worsening symptoms and a more significant impact on function. How multiple sclerosis progresses with age is gaining significant interest from researchers who want to learn more about how the changes we experience as we age impact MS. An important goal of the research is to identify what can be done to limit the effects of aging on MS.

As you get older, you are likely to have fewer relapses, fewer enhancing (inflammatory) lesions seen on an MRI, and, at the same time, more disability. A smoldering process that takes place within the brain and includes ongoing low-level inflammation may be the most significant driver of disease progression and accumulation of disability. Disability, like everything in MS, varies widely among individuals. More recent research indicates that MS disease worsening and increased disability is not just related to your numerical age or chronological age, but rather your biological age – or the extent of cellular changes and decline in function that occur over time.

Biological Aging in MS

Biological aging is individualized and can be caused by multiple factors, including genetics, environment, lifestyle, and disease course. Biological aging is often associated with chronic conditions such as type 2 diabetes, cardiovascular disease, and dementia. This is because your DNA protection diminishes over time when structures known as telomeres shorten. Telomere shortening is associated with changes in cell function and, for people with MS, may occur earlier than in people without MS. This shortening contributes to the damage that takes place in the brain and spinal cord over time.

For example, with biological aging, cells known as microglia become more activated and are known to contribute to the slow smoldering inflammation within the brain. Activated microglia also produce chemicals that damage myelin, cells that make myelin, and the nerves underlying myelin. Other immune system cells will also behave differently over time.

As our immune cells change with age, some become more inflammatory, and others have less regulatory ability – or the ability to regulate the immune response. There is also less ability for remyelination due to diminished activity of the cells that become myelin-making cells.

The immune system response, needed for fighting infections, also diminishes over time – a process known as immunosenescence. This causes the response to infections to be compromised, making infections riskier and the need for immunizations paramount. In addition, in MS, an older immune system may respond differently to MS DMTs.

What Does This Mean For You?

Well, none of this really sounds great. But there is good news.

New treatments are under study that target the immune system cells operating inside the brain – potentially reducing the detrimental impact of activated cells, like B lymphocytes and microglia. A class of MS DMT in late-stage development is the BTKi or Bruton’s tyrosine kinase inhibitor. BTK is necessary for B cells to mature and proliferate and for microglia to become activated. So, an inhibitor of BTK could be helpful in more progressive multiple sclerosis. There are several BTKi’s under study for the treatment of MS – including non-relapsing secondary progressive MS.

In addition, lifestyle can have an impact on some of the changes associated with biological aging. For example, exercise and physical activity may reduce cellular aging. It has been noted that consistent exercise in healthy adults can lead to an almost 9-year aging advantage, measured by telomere length.

Discerning Multiple Sclerosis Progression vs Normal Aging

Getting older and having multiple sclerosis also brings the question, “Is it my MS or am I just getting older?”  The answer may be both. As we age, various unwanted changes occur – stiffness, less endurance, bladder problems, and memory issues – to name a few. Progressive MS symptoms can seem similar. In either case, a thorough assessment is needed to determine the potential cause of the symptoms.

Treatment will often involve rehabilitation strategies and lifestyle changes.  Physical or cognitive rehabilitation may help improve function, while lifestyle changes like diet, exercise, better sleep and more may improve symptoms related to aging.

Talk to your primary care provider and your MS provider about the changes you are experiencing to sort through potential causes and find strategies that may help. Stay updated with our monthly newsletter for more information about symptom management and new medications on the horizon for MS.