The Push to Diagnose MS Years Before Symptoms Start

WebMD

5 days ago

Aug. 13, 2025 – What if a blood test could flag multiple sclerosis years before symptoms start?
Amid recent breakthroughs in diagnosis and treatment – like advanced MRI techniques and powerful B-cell depletion therapies – scientists say the next frontier in MS care could be prevention. They believe they're on the path toward being able to identify the disease before full symptoms appear, during what's known as the "prodromal" phase. This could give doctors a chance to intervene in the teenage or early adulthood years, potentially preventing a condition that can lead to serious disability or neurological decline.
Although it would be many years before such a test becomes available, scientists are laying the groundwork now.
Canadian researchers recently analyzed health care visit patterns for more than 10,000 people over 25 years and found that those who eventually developed MS had a clear pattern of doctor visits that differs from those of the general population.
Among the findings: A dozen years before their MS diagnosis, patients visited psychiatrists at more than double the rate, compared with people of the same age, gender, and geographic region who did not go on to be diagnosed with MS.
What that means, said senior author Helen Tremlett, PhD, is that "people were already changing" during their early to mid-20s, since the average age of the start of MS in the study was 37.
A Pattern Stretching Back 15 Years
The pattern of health care visits revealed in the study aligns with existing knowledge about early MS symptoms, which include the kind of nondescript health issues – like pain, fatigue, headache, dizziness, anxiety, and depression – that can be challenging for doctors to diagnose.
Particularly striking was just how many years before MS onset the pattern of doctor's visits started:
15 years: A decade-and-a-half before clear symptoms developed, people who would eventually develop MS had a 19% higher rate of visits to a general practice doctor, and they were more likely to have doctor visits for "ill-defined symptoms" like fatigue or pain.
12 to 14 years: Mental health visits were markedly higher at 14 years before diagnosis, with a rise in psychiatric visits starting at 12 years and escalating after that.
8 to 9 years: Eye pain and blurry vision are common MS symptoms, and people eventually diagnosed were more likely to seek neurology and ophthalmology care starting eight to nine years earlier.
3 to 5 years: Emergency room visits and radiology visits for medical imaging were higher than those of the general population starting around three to five years before diagnosis.
1 year: The year before an MS diagnosis, doctor visits across specialties peaked.
Tremlett, a professor at the University of British Columbia in Vancouver, Canada, cautioned that MS is still uncommon, affecting about 1 million people in the U.S.
"The vast majority of people who visit a doctor for the issues we identified do not develop MS and will not develop MS," she said. "No one should feel alarmed or concerned by our findings."
Indeed, extra doctor visits for fatigue or pain are not reasons to get an MRI (magnetic resonance imaging) scan to check for MS-related brain lesions, and it's certainly not feasible to test everyone who frequently sees a psychiatrist for depression or anxiety.
"We cannot use any of these findings – because they're too general – to accurately identify someone who goes on to develop MS. But I think it's really inspiring to think about: What else do we need? Where do we go to next?" Tremlett said, suggesting that perhaps one day, a person's age, gender, family history, and health care visit pattern could help identify whether they're at high risk.
"But here's the key point," she added. "You need to include something more specific."
What's really needed, she said, is a blood test. And Yale School of Medicine researchers in New Haven, Connecticut, are working on just such a test.
Why a Blood Test for MS Is Not a Far-Fetched Idea
Yale professor David Hafler, MD, has studied MS for nearly 50 years. His pivotal research, spanning five decades, identified MS as an autoimmune and genetic disease. A team at his lab is now studying people with a strong family history of MS – an effort that has tallied some 250 genetic variations that heighten risk – with the aim of developing a blood test.
The key, Hafler said, is to monitor those who haven't yet had the Epstein-Barr virus (EBV) – an infection that usually doesn't have symptoms and spreads through saliva and body fluids; it infects about 90% of people by age 25. A groundbreaking 2022 study linked the virus to MS.
Hafler suspects that in some people, EBV leads to breaking of "tolerance" – that is, it disrupts the immune system's ability to tolerate its own cells. This leads the body's autoreactive T cells to attack healthy cells.
Tremlett's study fits the working model many scientists are using of a prodromal phase of MS, Hafler said.
"What's happening is the disease is percolating," Hafler said. "I think there is a first stage before the T cells go into the brain, which is what leads to MS."
He and his colleagues are watching for changes in blood samples of people being studied after EBV is first detected.
The idea: "If someone starts to develop autoreactive T cells, for example, after an EBV infection, I would treat them with B-cell depletion," Hafler said, noting that much more research would be needed before taking that step.
Even if a blood test were to be developed, it could raise ethical challenges. Some people have MS that isn't severe, or they have brain lesions identified on an MRI ordered for a different reason and they never go on to develop symptoms. In these scenarios, B-cell depletion treatment might not be worth the potential side effects, like a weakened immune system.
Also on the horizon is genetic testing for MS. While not yet available outside of research trials, it's getting more accurate, Hafler said. Alongside those known 250 genetic variants, scientists are examining risk among people whose parents (one or both) have MS. "We haven't validated this yet, and it's not a test you can order," he said, "but the statistics tell us that if you're in the top 10 percentile [of carrying risk-associated genetic variants], you probably have a 1 in 10 chance of developing MS."
With the latest research confirming the condition's long prodromal period, "the next step should be identifying patients at risk, and then to monitor them in the moment they show signs of developing MS biomarkers," Hafler said.
What to Do if You're Worried About MS
It's unlikely that someone with the health care visit patterns revealed in the recent study would be at risk of multiple sclerosis, said MS specialist Brittani Conway, MD, of the University of Minnesota. That said, she also encourages people to advocate for themselves if they think they are having early warning signs.
"Trust your intuition," she said. "A lot of patients with MS do actually come to me with a bit of PTSD from their experience of being shuffled around the health care system."
Perhaps, for someone who has a first-degree relative with MS, such a pattern or a sudden change could be worth a discussion with your doctor, Hafler said.
Conway's advice is to "maintain that determination that there may be something off, even if it's not showing up right away."
Also, remember that lifestyle changes – like eating healthy, exercising, and quitting smoking – are all key treatments for MS and for mood disorders, alike.
"Focus on what is in your control," Conway said. "Focusing on lifestyle will be very helpful, and it's something that is within the power of the patient even before their diagnosis."