As Europe plans its response to the neurological disease burden, a fundamental measurement gap is being overlooked — and the cost of ignoring it is being felt.
A briefing requested earlier this year by the European Parliament’s Committee on Public Health (SANT) put it plainly: neurological diseases are one of Europe’s most urgent and rapidly expanding health, social and economic challenges. Published in February 2026, it calls for a coordinated European plan linking prevention, early diagnosis, research and innovation. But before Europe considers what that plan should look like, a foundational question demands attention: are we measuring the right things?
Multiple sclerosis (MS), a chronic, progressive disease of the central nervous system that disrupts communication between the brain and the body, offers a revealing case study. Consider a woman in her mid-30s, working, raising a family, managing what her neurologist calls “stable” MS. She has not slept properly in years, her memory has been slipping and she is cutting her hours at work. Her last clinical note reads: “No change.” On paper, she is stable, but in reality she is anything but.
Her story is not unusual. According to research commissioned by Sanofi, the gap between what health systems measure and what people with MS experience may be costing individuals, families and economies more than we realize.
The stakes for Europe
Over 3 million people globally live with MS and Europe has the highest prevalence, at 133 per 100,000 people. The condition strikes primarily during prime working years, meaning hundreds of thousands of people are navigating a progressive, unpredictable disease at precisely the point when inadequate support is felt most acutely.
That support begins with measurement. And right now, the tools used to assess MS in clinical practice do not fully capture what people with the disease experience.
The consequences extend far beyond the clinic: 82 percent of people with severe MS rely on unpaid family caregiving, yet this burden rarely appears in standard health data or policy design. When the full impact of disease is not measured, health systems can underestimate need, delay support, and overlook the wider effects on work, welfare and family life.
The measurement gap
The Expanded Disability Status Scale (EDSS), the primary tool used to measure MS disability, was developed in 1983 to assess walking ability. We now know that MS affects far more than mobility. Fatigue affects 94 percent of people with MS, while 75 percent report cognitive difficulties, but both are absent in the EDSS assessment. In a field where clinical consensus is rare, seven in ten neurologists agree: a more comprehensive approach is needed.
Growing recognition of smouldering neuroinflammation has made the need for new methods of quantifying MS progression increasingly urgent. This slow, chronic disease activity can persist even when a patient appears clinically stable, with effects that are subtle, cumulative and easy to miss until significant damage has already occurred.
This is why Sanofi initiated the development of the Smouldering Associated Worsening (SAW) Index. The SAW Index Study — led by an international steering committee of leading MS clinicians, researchers and patient advocates — is due to complete in 2027. Based on hundreds of hours of in-depth qualitative research with people with MS, the goal of the SAW Index is to provide neurologists with a comprehensive measurement framework that bridges the gap between lived experience and what clinical tools are currently able to detect.
According to the European Multiple Sclerosis Platform, people with MS experience an average of 14 symptoms within the first five years of diagnosis, with fatigue, sensory problems, sleep disturbances, cognitive impairment and balance problems among the most common. These are precisely the experiences the SAW Index is designed to surface, replacing static labels like “moderately affected” with measurement metrics grounded in the experience and words of people with MS.
The cost of this gap
These aspects of MS can be challenging to quantify and are associated with substantial societal and economic burdens. Lifetime productivity loss per person with MS ranges from €394,000 in France to €668,000 in Germany. The cost profile shifts significantly as the disease progresses: in mild MS, direct healthcare costs dominate; in severe MS, indirect costs become the primary driver. Indeed, lost wages, absenteeism, early retirement, disability payments and the growing burden on unpaid carers outweigh medical costs in many countries, placing growing long-term pressure on social insurance and disability systems.
Early identification of progression could change that trajectory, extending years of employment, preserving household income, and reducing long-term dependence on disability and social benefits. That is a cost-avoidance opportunity current measurement frameworks are missing.
Progress in motion
There is no single fix, but there is momentum.
MS care has advanced significantly in recent decades: diagnosis is happening earlier, treatment options have expanded and the focus is shifting from relapse control alone to slowing long-term disability progression. Furthermore, there is growing recognition of the importance of cognition, mental health, rehabilitation and the day-to-day realities that shape whether people living with MS can remain independent and active.
The challenge now is to ensure policy keeps pace with that progress, and better measurement is part of the answer. If Europe wants health spending to deliver lasting value, it should see these improvements not as costs to be managed, but as investments in independence, participation, productivity and more sustainable health systems.
Time to act
The European Parliament’s SANT Committee has called for a fully funded European neurological health plan — one with the scale and ambition of Europe’s Beating Cancer Plan, aligning health, research and societal action in a unified framework. MS offers a clear and immediate test case for what that ambition looks like in practice.
But ambitious plans require accurate data. If Europe is serious about a coordinated response to neurological disease, getting measurement right is not a secondary concern; it is the foundation on which everything else depends.
The people living with MS across the continent cannot wait for the tools that measure their disease to catch up with the science that understands it. Neither should policymakers.
