Although most people with multiple sclerosis (MS) are aged 20–40 years when symptoms appear, the condition can sometimes develop later in life. When MS appears in older adults, doctors may refer to it as late onset multiple sclerosis (LOMS).


MS is an autoimmune disorder that affects the central nervous system. In people with autoimmune conditions, the immune system mistakenly attacks healthy cells as though they were pathogens.

With MS, the immune system attacks the myelin sheath that surrounds and protects nerve fibers. This attack causes scarring, or sclerosis, which impairs the smooth flow of electrical impulses from the brain to the target nerve. As a result, the body can no longer carry out certain functions.

Most people with MS get a diagnosis between the ages of 20 and 40 years. However, the condition can present outside of this age bracket. Diagnosing older adults with MS can be challenging because people may mistake their symptoms for the typical signs of aging.

In this article, we look at the symptoms, causes, diagnosis, and treatment of late onset MS. We also discuss how to live with the condition.

A doctor diagnosing someone with late onset multiple sclerosis.Share on Pinterest
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LOMS is the term for MS that manifests in older age, typically after the age of 50 years. Some doctors may also refer to it as later-onset MS.

LOMS may present slightly differently to MS in a younger person. For instance, some symptoms may occur more frequently in LOMS, there may be fewer relapses, and the progression of disability is generally faster. It can be difficult to diagnose MS at any age, but it is typically harder with LOMS, as doctors must consider other age-related causes when making a diagnosis.

Other than appearing later in life, the symptoms of LOMS are often the same as those of regular onset MS.

Common symptoms of MS include:

  • a squeezing sensation around the torso, also known as MS hug or dysesthesia
  • fatigue
  • difficulty walking
  • weakness
  • dizziness
  • balance issues
  • spasticity
  • numbness and tingling
  • vision problems
  • bladder dysfunction
  • sexual problems
  • bowel problems
  • pain and itching
  • difficulty with problem-solving, attention, and focus
  • emotional changes
  • depression

Research suggests that the key symptoms of LOMS are motor dysfunctions, sensory disturbances, and visual impairments.

LOMS and regular onset MS likely share the same causes. Experts do not fully understand what causes MS, but they believe that various factors trigger the immune system to attack the myelin sheath. According to the National Institute of Neurological Disorders and Stroke, possible causes include:

Genetics

Although MS is not a hereditary condition, people may inherit a susceptibility to developing it. Research suggests that many genes and gene variations may combine to create vulnerability to MS. Some of these genes are associated with functions of the immune system and are similar to those that may cause other autoimmune conditions.

Environmental factors

Some research suggests that people who spend more time in the sun and those with higher levels of vitamin D are less likely to develop MS. This reduced risk may be due to how vitamin D helps regulate the immune system.

The National Multiple Sclerosis Society notes that those who smoke are more likely not only to develop MS but also to have a more aggressive disease course.

Infections

Some evidence links viruses — particularly the Epstein-Barr virus (EBV), which causes infectious mononucleosis — to the development of MS. A previous infection with EBV may significantly increase a person’s risk of developing MS. However, this indicates that the immune response to EBV may lead to MS, rather than the EBV infection itself.

It can be difficult for doctors to diagnose LOMS because older adults, especially those much older than 50 years, may confuse the symptoms with those of other conditions. Some people may also mistakenly assume that the symptoms are a normal part of aging.

According to a 2014 review, LOMS is rare. However, as MS is already difficult to diagnose in younger people, diagnosing LOMS may be even more challenging. Other research notes that due to these difficulties, doctors may underdiagnose or misdiagnose LOMS.

A doctor will likely diagnose LOMS in a similar way to regular onset MS. As well as asking the individual about their symptoms and medical history, the process will typically involve a physical and neurological examination. As no single test can confirm a diagnosis, a doctor may use multiple methods, such as:

  • MRI scans of the brain and spinal cord, which may reveal scarring on the myelin sheath
  • an evoked potential test, which measures electrical activity in response to stimuli
  • spinal fluid analysis, which may identify antibodies that suggest a previous infection

A doctor may also require additional tests to rule out other possible conditions.

Learn more about testing for MS.

As LOMS typically has a rapid disease progression, prompt treatment can help a person avoid a quick decline. Although there is currently no cure for MS, treatment can help people manage symptoms and maximize their quality of life.

Treatment options may involve:

  • disease-modifying medications to prevent and reduce the severity of MS relapses
  • drugs to treat specific symptoms, such as itching, pain, and bladder dysfunction
  • corticosteroids to minimize inflammation
  • rehabilitation to help with energy management, mobility, and cognitive functioning
  • mental health support to help a person cope with depression or other emotional changes that occur because of MS

According to a 2017 study, people who have LOMS are likely to have a less positive outlook than those who experience symptom onset before the age of 50 years. People with LOMS typically experience more severe disability over time, regardless of how mild the symptoms are at the point of diagnosis.

Prompt treatment may mitigate this quick disease progression and help a person manage their symptoms. However, the challenges around diagnosis mean that this is not always easy.

Learn more about living with MS.

The National Multiple Sclerosis Society states that caregivers caring for someone with MS can help by:

  • Seeking support: Caregivers should be careful not to neglect their own emotional and physical health. They can try confiding in other loved ones or seeking out support groups specifically for caregivers.
  • Planning for unpredictability: Caregivers should not avoid making plans. However, they should allow for flexibility when arranging outings and keep things simple to avoid distress. It is a good idea to have the phone numbers of trusted people who can help at short notice.
  • Getting help: Sometimes, there are too many household tasks to take on all alone. If a person has the financial means, they may want to hire someone to help with household or caregiving tasks.
  • Looking into available financial resources: Depending on the area in which a person lives, they may have access to assistance programs to help with caregiving.

Most people with MS receive a diagnosis between the ages of 20 and 40 years. However, the condition can appear at a younger or older age. When a person develops symptoms of MS after reaching the age of 50 years, a doctor may refer to this as LOMS.

Research suggests that LOMS is relatively rare. However, diagnosing MS is even more difficult than usual in older people, so misdiagnosis is a possibility. People with LOMS tend to have faster disease progression than those who experience onset at a younger age.