Although most people with multiple sclerosis (MS) are 20 to 40 years old when symptoms appear, MS can occasionally develop later in life. When MS appears in adults over 50, doctors may call it late onset multiple sclerosis.
MS is an autoimmune disorder that affects the central nervous system. In people with autoimmune conditions, the immune system mistakenly attacks healthy cells.
With MS, the immune system attacks the myelin sheath that surrounds and protects nerve fibers. This attack causes inflammation, which may cause scarring that impairs the smooth flow of electrical impulses from the brain to the target nerve. As a result, the body can no longer do certain functions.
Diagnosing MS in older adults can be challenging because doctors may first consider other health conditions that develop with age.
This article looks at the symptoms, causes, diagnosis, and treatment of late onset MS (LOMS).
Other than appearing later in life, the symptoms of LOMS are often similar to those of regular onset MS. Some common symptoms of MS include:
- a squeezing sensation around the torso, also known as an 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
That said, LOMS may present slightly differently than MS in a younger person. A 2020 analysis of previous research suggests that some symptoms may occur more frequently in LOMS. The progression of disability is also generally faster.
The key symptoms of LOMS appear to be:
- motor dysfunction
- sensory disturbances
- visual impairments
Experts do not fully understand what causes MS, but they believe various factors trigger the immune system to attack the myelin sheath.
According to the
Genetics
Although MS is not a hereditary condition, people may inherit a susceptibility to developing it. 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.
People who smoke are
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. This indicates that the immune response to EBV may lead to MS, rather than the EBV infection itself.
A doctor will likely diagnose LOMS as they would regular onset MS.
The diagnostic process typically involves a doctor asking about the person’s symptoms and medical history, and performing a physical and neurological examination.
As no single test can confirm a diagnosis, a doctor may use multiple methods,
- MRI scans of the brain and spinal cord, which may reveal inflammation or scarring around the myelin
- an evoked potential test, which measures electrical activity in response to stimuli
- spinal fluid analysis, which may identify proteins and antibodies that are common in MS
A doctor may also order additional tests to rule out other possible conditions.
It can be difficult to diagnose MS at any age, but it is typically harder with LOMS, as doctors may mistake its symptoms for other conditions. Some people may also mistakenly assume that the symptoms are a normal part of aging.
According to a 2022 study, LOMS is rare. However, other research notes that due to the difficulty of diagnosing LOMS, doctors may underdiagnose or misdiagnose the condition. It is possible that LOMS may be more common than data suggests.
Because LOMS typically has a rapid disease progression, prompt treatment can help prevent or delay worsening symptoms.
There is currently no cure for MS, but treatment can help people manage symptoms and maximize their quality of life.
Treatment options may include:
- 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 during episodes of worsening symptoms
- rehabilitation to help with energy management, mobility, and ability to think
- mental health support to help a person cope with depression or other emotional changes that occur because of MS
People caring for someone with MS can help by:
- Seeking support: Caregivers need to be careful not to neglect their own emotional and physical health. They can try talking with other loved ones or seeking support groups specifically for caregivers.
- Planning for unpredictability: Caregivers should allow for flexibility when arranging outings and keep things simple to avoid distress if symptoms occur. 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 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.
Here is a list of MS support groups for individuals and caregivers.
According to a 2017 study, people who have LOMS are likely to have a less positive outlook than those who experience symptom onset before age 50 years.
People with LOMS typically experience more severe disability over time, regardless of how mild the symptoms are at the time of diagnosis.
Prompt treatment may hinder this quick disease progression and help a person manage their symptoms. However, the challenges around diagnosis mean that this is not always easy.
Most people with MS receive a diagnosis between 20 and 40 years old. However, MS can appear at a younger or older age. When a person develops MS symptoms after age 50, a doctor may call it late onset MS (LOMS).
Research suggests LOMS is relatively rare. However, there can be delays in diagnosing older adults, as there are other causes for the symptoms doctors may investigate first.
People with LOMS tend to have faster symptom progression than those who experience onset at a younger age, but treatments are available to reduce the symptoms and slow the disease.