• Posted August 4, 2025

MS May Begin Years Earlier Than Thought

People with multiple sclerosis (MS) begin experiencing new health issues up to 15 years before the classic signs of the illness appear, Canadian research shows.

“MS can be difficult to recognize as many of the earliest signs — like fatigue, headache, pain and mental health concerns — can be quite general and easily mistaken for other conditions,” study senior author Helen Tremlett noted.

“Our findings dramatically shift the timeline for when these early warning signs are thought to begin, potentially opening the door to opportunities for earlier detection and intervention,” said Tremlett, a professor of neurology at the University of British Columbia, in Vancouver.

Her team published its findings Aug. 1 in JAMA Network Open.

MS is an autoimmune illness in which the body’s immune system goes awry, attacking the protective myelin sheath that surrounds nerves within the brain and along the spinal cord. 

Communication breaks down between the brain and the body, leading to progressive disability. 

The new study that suggests MS may begin more than a decade before a clinical diagnosis.

Tremlett’s group combed through British Columbia health data for 12,000 people with or without MS. Records went back as far as 25 years prior to an MS patient’s diagnosis. 

That’s far longer than the five to 10 years covered in earlier studies looking at disease onset.

The main findings: 

• Fifteen years before the onset of classic MS symptoms, there was a noticeable uptick in patient visits to their general practitioner, or in visits to specialists for issues like fatigue, pain and dizziness, as well as mental health issues such as anxiety and depression.

• Twelve years before symptom onset, visits to psychiatrists began to rise.

• Eight to nine years before, visits to neurologists and eye specialists rose, perhaps linked to issues such as blurred vision or eye pain.

• Three to five years before, researchers noted a rise in visits to emergency departments and/or radiology facilities.

• One year before, visits peaked for a wide range of different physician types, such as neurologists, radiologists and emergency doctors.

“These patterns suggest that MS has a long and complex prodromal phase — where something is happening beneath the surface but hasn’t yet declared itself as MS,” said study first author Dr. Marta Ruiz-Algueró, a postdoctoral fellow at UBC. 

“We’re only now starting to understand what these early warning signs are, with mental health-related issues appearing to be among the earliest indicators,” she added in a news release.

The researchers stressed that the early issues that drove MS patients to seek out care can be caused by a myriad of health conditions. Simply experiencing these conditions does not mean a person will go on to develop MS.

Nevertheless, “By identifying these earlier red flags, we may eventually be able to intervene sooner — whether that’s through monitoring, support or preventive strategies,” Tremlett said a university news release. “It opens new avenues for research into early biomarkers, lifestyle factors and other potential triggers that may be at play during this previously overlooked phase of the disease.”

More information

Find out more about multiple sclerosis at the National Multiple Sclerosis Society

SOURCE: University of British Columbia, news release, Aug. 1, 2025