A person can spend more than a decade visiting doctors for exhaustion they chalk up to overwork, anxiety they manage with therapy, or pain they attribute to stress – all while a chronic neurological disease has already begun to take hold. For hundreds of thousands of people living with multiple sclerosis, this is the story. Researchers are mapping in detail the years between the body first signaling something is wrong and the moment a neurologist finally names it.
Multiple sclerosis has long been understood as a disease that arrives abruptly: sudden vision loss, a limb that goes numb, a strange electrical sensation down the spine when you tilt your head forward. These landmark symptoms prompt urgent investigation. The new picture emerging from large-scale health record analysis is considerably more unsettling: the nervous system may be under attack for well over a decade before any of those unmistakable neurological events appear. The body is sending signals that are too general, too easy to explain away, and too easily dismissed by both patients and physicians.
For women, who are diagnosed with MS at roughly three times the rate of men, the stakes of that long diagnostic gap are particularly high. The early signs that precede formal diagnosis by up to 15 years – fatigue, anxiety, vague pain, depression – are precisely the symptoms most routinely minimized in women’s healthcare encounters.
The Landmark Study: 25 Years of Health Records, One Striking Finding
Published on August 1, 2025, in JAMA Network Open, the study analyzed the health records of more than 12,000 people in British Columbia and found that those with MS began using healthcare services at elevated rates 15 years before their first MS symptoms appeared.
Conducted at the University of British Columbia and associated MS clinics, the study compared physician visits of patients with MS against a matched group of individuals without the condition. The study introduced an extended observation period, examining healthcare use over 25 years rather than the typical 5 to 10 years examined in previous research. That extended window made the 15-year finding possible.
The findings challenge long-held assumptions about when the disease truly begins, offering the most comprehensive picture to date of how patients engage with healthcare providers in the years leading up to a diagnosis as they search for answers to ill-defined medical challenges.
The senior author of the study, Dr. Helen Tremlett, a professor in the Division of Neurology at UBC, and her team have built on prior work to characterize the MS prodromal phase. The term “prodrome” refers to an early or preliminary stage of disease during which symptoms exist but have not yet become specific enough to name. Prodromal periods are well established in other neurological disorders, like Parkinson’s disease, where mood changes, sleep disturbances, and constipation often arise years before tremors and stiffness. The 2025 study now places MS firmly in that same category.
What the Symptom Timeline Actually Looks Like
The research did not find a uniform surge in healthcare use across all specialties at once. Instead, it revealed a layered, sequential pattern of increased physician contact that tracks with what the body is experiencing as the disease begins to develop.
Visits for general or ill-defined symptoms – fatigue, dizziness, or feeling unwell without a clear diagnosis – were more common starting 15 years before the onset of symptoms. Visits related to mental health problems such as anxiety and depression were more frequent in the 14 years before symptoms, and visits to psychiatrists began as early as 12 years before.
Visits to neurologists and ophthalmologists became more frequent in the last eight to nine years before symptom onset. That timing makes clinical sense: neurological and vision-related concerns are the ones most likely to prompt investigation of the central nervous system. The data shows that the body had already been generating signals for six or seven years before those more specific complaints began to emerge.
In the year before symptoms appeared, neurologist visits were more than five times as high for people who went on to develop MS compared with those who did not. By that point, the clinical picture was becoming harder to ignore. The documented tragedy is the decade-plus of diffuse, easily explained symptoms that preceded it.
As Dr. Tremlett noted, “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.”
The Prodromal Phase: Why MS Begins Long Before It Announces Itself
According to Dr. Marta Ruiz-Algueró, the study’s first author and a postdoctoral fellow at UBC, “MS has a long and complex prodromal phase – where something is happening beneath the surface but hasn’t yet declared itself as MS. 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.”
Multiple sclerosis is an autoimmune condition in which the immune system attacks myelin, the protective sheathing around nerve fibers in the brain and spinal cord. The attack causes scars, or lesions, that make it harder for signals to travel between the brain and the body. The prodromal phase is the period during which immune dysregulation is occurring, but before enough demyelination has accumulated to produce the focal neurological symptoms that would trigger MRI investigation.
The vast majority of people who experience general symptoms will not go on to develop MS. What the study identifies is a pattern – a durable, multi-domain increase in healthcare use that differs statistically and meaningfully from the control population. That pattern is a research-level signal, not a diagnostic checklist.
Dr. Tremlett said, “By identifying these earlier red flags, we may eventually be able to intervene sooner – whether that’s through monitoring, support or preventive strategies,” adding that the findings “open 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.”
MS and Women: A Disease That Disproportionately Strikes, and Is Disproportionately Missed
According to the National MS Society, nearly 1 million people in the United States are living with MS, with more than 450 new cases diagnosed each week in the country. Within that population, the gender disparity is substantial. Women are three times more likely to have MS than men.
That elevated prevalence has biological roots. Estrogen and other sex hormones influence immune regulation, and women generally mount stronger immune responses than men – a protective advantage against infection that carries the counterweight of higher susceptibility to autoimmune conditions. MS is not the only disease that falls into this pattern: autoimmune diseases, including lupus and rheumatoid arthritis, show a similar female predominance linked to hormonal and immune factors.
Among women, MS may appear at an earlier age and cause more lesions in the brain and spinal cord. Anxiety and fatigue are more common symptoms for women with MS. These symptoms are also the ones most likely to be attributed to life circumstances, hormonal fluctuation, or stress rather than neurological disease. A 34-year-old woman who reports to her primary care physician that she is persistently exhausted and has been struggling with anxiety for the past two years is unlikely to prompt a neurological workup. She may leave with a depression screening tool and a suggestion about sleep hygiene.
MS is often described as unpredictable, and one of the most challenging aspects is that its earliest signs are easy to dismiss. A brief episode of blurry vision, a strange tingling in the arm, and unusual exhaustion are experiences many people attribute to stress or aging. In some cases, these are the first signals the nervous system sends when something more significant is happening.
The Specific Early Warning Signs: What the Data Reveals
The UBC study identified a specific escalation sequence across multiple domains of healthcare use.
Mental Health Presentations
Visits driven by anxiety, depression, and general psychological distress began diverging from the control population approximately 14 years before the first recognizable MS symptoms. Psychiatric consultations specifically became more frequent around the 12-year mark. Researchers found that future MS patients had elevated rates of mental health-related issues, psychiatrist and general practice visits, and complaints of vague symptoms such as fatigue and pain all as early as 15 years before the onset of clear symptoms.
Fatigue, Pain, and Ill-Defined Complaints
General symptoms without a clear diagnosis – classified in health records as “ill-defined” – were consistently elevated throughout the prodromal window. Fatigue is the most reported symptom of MS overall. Among the most difficult aspects of MS can be its “invisible” impacts: fatigue and mood swings, along with other symptoms that do not appear on imaging or blood work and therefore resist documentation. These are the complaints that generate repeated primary care visits, inconclusive testing, and eventual reassurance that nothing is structurally wrong. Nothing is detectably wrong yet.
Neurological and Ophthalmological Concerns
Neurology and ophthalmology consultations, which are more directly tied to MS early signs, increased notably only eight to nine years before diagnosis. Vision disturbances are among the most recognized early signs of MS, particularly optic neuritis – inflammation of the optic nerve that can cause pain with eye movement and temporary loss of vision in one eye. Inflammation of the optic nerve, called optic neuritis, affects approximately 50% of people with MS and is often the first noticeable symptom.
The Final Year: A System in Overload
In the year before the onset of recognized MS symptoms, physician visits across multiple specialties peaked, including neurology, emergency medicine, and radiology. This escalation pattern in the final 12 months reflects a body that is producing symptoms clear enough to demand specialist referral and imaging. By this stage, most patients are either already diagnosed or very close to receiving a diagnosis. The decade preceding that final escalation is where neurological function can best be protected.
The Diagnostic Delay Problem and Why It Persists
The UBC findings are striking because they document a systematic pattern of healthcare contact that did not, for most patients, lead to earlier identification.
General practitioners working through a differential diagnosis for fatigue and anxiety face a long list of more common explanations: thyroid dysfunction, anemia, sleep disorders, depression, perimenopause. MS is a less common condition, and without a specific symptom that directs attention to the central nervous system, it often does not make the short list.
The relapsing-remitting nature of early MS compounds this problem. This pattern – in which symptoms appear, partially resolve, and return – accounts for approximately 85% of MS diagnoses. When a symptom goes away on its own within a few days, the patient may not return to report it, or the physician may conclude that resolution indicates a benign cause. It is only in retrospect, looking at the full pattern over years, that the significance becomes clear.
Implications for Clinical Practice and Future Research
The UBC findings carry a concrete promise: if the prodromal phase can be characterized precisely enough, it may eventually become the target of earlier intervention.
Disease-modifying therapies for MS work by reducing the frequency and severity of relapses and slowing the accumulation of lesions in the brain and spinal cord. The earlier those therapies begin, the more neurological reserve the patient retains. There is a meaningful clinical difference between starting treatment at the first recognizable attack and starting it years later after multiple silent episodes of demyelination have occurred.
The research team is pointing toward the next generation of studies that the prodromal findings make necessary. Building on that baseline, researchers can now work toward identifying biological markers – proteins in blood or cerebrospinal fluid, patterns on advanced MRI sequences – that might flag high-risk individuals during the prodromal window, before any focal neurological event has occurred.
What to Do With This Information
The single most important shift that the 2025 UBC study demands is understanding what “early” means in the context of MS. For decades, early MS has been understood as the period following a first clinical attack. The new data relocates that boundary to more than a decade before that attack, in a period when the patient’s primary complaints are indistinguishable from a dozen other common conditions.
For patients, this does not translate into a mandate for alarm at every episode of fatigue or bout of anxiety. Both of those experiences are common and rarely indicate neurological disease. What the research does support is persistent curiosity about symptoms that recur without a satisfying explanation – fatigue that does not respond to rest, anxiety that does not respond to treatment, pain that moves or disappears and reappears without a structural cause. A pattern of unexplained, multi-domain symptoms across several years is different from a rough month. Communicating that difference clearly to a physician – and insisting on follow-up when the first explanation does not hold – is exactly what the data supports.
For clinicians, the data makes the case for considering MS further up in the differential when a patient – particularly a woman in her 30s or 40s – presents repeatedly with fatigue, anxiety, or diffuse pain without a consolidating diagnosis. No single visit produces this signal. The pattern is visible only across time, which means primary care records, honestly reviewed across multiple years, carry diagnostic weight that may be currently underused. The opportunity identified by this research is not a new test or a new drug. It is a different way of reading a medical history that has been sitting in the chart all along.
Disclaimer: This information is not intended to be a substitute for professional medical advice, diagnosis, or treatment and is for information only. Always seek the advice of your physician or another qualified health provider with any questions about your medical condition and/or current medication. Do not disregard professional medical advice or delay seeking advice or treatment because of something you have read here.
AI Disclaimer: This article was created with the assistance of AI tools and reviewed by a human editor.