January 23, 2026, 5:22 am | Read time: 14 minutes

Multiple sclerosis is an inflammatory disease of the central nervous system. It affects the brain and spinal cord of those affected. MS is characterized by relapses that can vary in severity and duration. Because multiple sclerosis can also present with countless different symptoms, it is often referred to as the “disease with a thousand faces.” According to the German Multiple Sclerosis Society, about 2.8 million people worldwide live with the autoimmune disease, with 280,000 in Germany. Approximately 15,000 new diagnoses are made each year.¹ “The number of affected individuals seems to be increasing,” Dr. Thilmann explained in a FITBOOK interview, suggesting various reasons for this trend. The expert also discussed in detail what makes multiple sclerosis so difficult to diagnose, how MS progresses, and the challenges faced by patients and treating physicians.

The Number of Ms Cases is Rising

FITBOOK: Why are the numbers of MS cases increasing?
Dr. Patrick Thilmann: “The scientific explanation for this increase is unclear. However, it is suspected that earlier diagnosis today means more cases are being detected.”

Improvements in Diagnosis

What has changed to allow earlier diagnosis today?
“Previously, a second relapse was required under diagnostic criteria to diagnose multiple sclerosis. After the first symptoms, one would wait for new symptoms to appear before making a definitive diagnosis. Today, it is known that individuals with certain abnormalities are highly likely to develop MS, leading to adjustments in the diagnostic criteria.”

Are there other explanations for why MS seems to be more common?
“It is suspected that environmental influences play a role in the increased occurrence of the disease today compared to the past. These could also explain why MS is now appearing in regions where it was previously rare. One hypothesis is that certain genes, which increase susceptibility to multiple sclerosis, have become more widespread. For example, there is a theory that so-called susceptibility genes, which increase disease susceptibility, were spread by the Vikings. Consequently, globalization may have further mixed these genes, bringing them to regions of the world previously unaffected.”

Possible Causes of the Disease

What are the causes of multiple sclerosis?
“Much is still unclear regarding the causes. On one hand, hereditary factors play a role. However, it is also clear that certain circumstances increase the likelihood of developing multiple sclerosis. A large military study in the U.S., which conducted systematic examinations of recruits, found that individuals who had an Epstein-Barr virus infection had a higher likelihood of developing MS. The virus appears to promote the development of multiple sclerosis. A similar connection with previous viral infections can be observed in cerebrospinal fluid: a positive so-called MRZ reaction (measles, rubella, varicella zoster) is specific for the presence of MS. Viruses seem to act as a trigger, meaning the immune system may react to these viruses. However, because the reaction is misguided, it eventually attacks the body itself.”

MS attacks the patient’s body. How can that be imagined?
“The attack on the body looks like this: the myelin sheath of the nerves, or the nerve covering, is damaged and eventually destroyed. This leads to the typical relapses associated with MS.”

Risk Factors for MS

You just mentioned that multiple sclerosis can be inherited. Can parents pass on the susceptibility to the disease to their children?
“In medical treatment, we repeatedly find that in some cases there is a familial clustering of MS. Indeed, the risk increases if the mother or father is already affected. If both parents are affected, the risk increases further. The situation with identical twins is interesting, as they do not necessarily both have to develop multiple sclerosis. Environmental factors also seem to play a role.”

Research is still working to solve existing MS puzzles. What is already known about environmental influences as risk factors for multiple sclerosis?
“Here, the classic lifestyle factors should be mentioned. Smoking is a risk factor: smokers have a higher likelihood of developing the disease and often experience a more unfavorable disease course. Obesity also plays a role. Finally, nutrition is of some importance. For example, a healthy vitamin D level has a protective effect. Studies also show that participants experience fewer relapses when given certain fatty acids, such as propionic acid.”

Nutrition – Both a Risk Factor and Part of Therapy

That brings us to living with MS and the treatment of multiple sclerosis. Is nutrition a key factor?
“We generally recommend a healthy diet to patients. An important aspect here is salt consumption. Classic table salt, for example, has an inflammatory effect. Furthermore, studies have indicated the negative impact of dairy products, particularly fresh milk, on MS. What exactly is behind this is still unclear, but studies show that patients with high milk consumption have higher disease activity. Research is ongoing in this area to determine whether certain foods not only negatively affect the disease course but also represent a risk factor for the onset of the disease.”

Symptoms of Multiple Sclerosis

Early Symptoms Are Often Subtle

Let’s take a step back: What are typical symptoms of multiple sclerosis?
“The most common symptom we see is numbness. Numbness is also a complaint that many patients initially overlook. Many of us know the feeling of limbs ‘falling asleep’ and do not immediately think of a serious illness. Early symptoms are often not taken seriously. Additionally, the complaints occur in the context of relapses, meaning they may last seven to ten days and then subside and disappear completely. This leads to most affected individuals not going to the doctor right away, as they do not fear anything serious and assume it is merely a temporary occurrence.”

Does MS always start so seemingly harmlessly, without lasting effects?
“Indeed, there are also patients who experience damage after the first relapse. Some affected individuals report, for example, that one hand still feels strange after the relapse, lacking fine motor skills—especially compared to the other hand.”

How else can the disease manifest in its early stages?
“The second most common symptom with which multiple sclerosis begins is optic neuritis. This leads to ‘veil vision’ in the affected eye. This means one sees as if through frosted glass, colors are not perceived as vividly, and reading becomes difficult. Red appears pale, and the eye muscle causes pain when moving the eye. With these complaints, affected individuals are more likely to see a doctor than when a hand tingles or is numb.”

Movement and Coordination Disorders Up to Paralysis Possible

MS also involves motor impairments, right?
“When there are inflammations in the cerebellum or brainstem, movement and coordination disorders can result. This can cause problems with grasping or writing, which can become uncoordinated. Patients may notice they walk unsteadily. One of my patients reported suddenly feeling dizzy, typically during movement. If the motor fibers are affected, meaning the nerve cells that transmit signals to the muscles, a patient can also develop paralysis. Typically, the legs are affected.”

Disease of a Thousand Faces

How else can multiple sclerosis manifest, in your experience?
“Multiple sclerosis is also referred to as the ‘disease of a thousand faces,’ indicating the wide range of symptoms. I have only listed a fraction so far. Many MS patients suffer from pain, and there are also individuals who develop bladder issues and/or sexual dysfunctions. Memory can also be affected over time. However, this is not dementia but rather partial performance disorders. Affected individuals may notice they suddenly have problems with multitasking or difficulties with attention and concentration. Many patients also suffer from fatigue syndrome, whose symptoms are very subjective and difficult to measure. The resulting impairment in the daily lives of those affected should not be underestimated. In summary, multiple sclerosis is very diverse in its manifestations and symptoms.”

Treatment Options

During an Acute Relapse

What does MS treatment look like?
“An acute relapse is typically treated with cortisone. Patients usually receive a high dose in the form of an infusion over five days. This can effectively manage a relapse, and the symptoms associated with it disappear more quickly.”

After a Relapse or Between Relapses

And when the relapse is over, what happens next?
“After the relapse, we perform MRI scans of the head and spine to get a picture of the inflammation sites. We determine how many sites the patient has and where they are located. We also consider individual factors such as the patient’s age, how long they have had MS, how many relapses they have had, and what they were like. This guides potential treatment.”

What might an MS treatment look like?
“Take the example of a patient who had their first relapse, with a few inflammation sites visible in the brain and no sites in the spinal cord. In such cases, there was a tendency to administer weakly effective medication. However, there is now evidence that it seems better to treat MS patients from the start with more effective and potent medications, as this leads to a more favorable long-term disease course. Therefore, there is a tendency today to forgo mildly effective medications.”

So, do you always start with stronger medications now?
“This cannot be generalized, as it also depends on the patient’s wishes. There are clearly cases where patients respond well to weaker medications and manage well with them. However, if a patient has sites in the brain and lesions in the spinal cord—factors known to be associated with a poorer disease course and earlier onset of disabilities—it is advisable to treat them with stronger medications from the start. In this case, you do not want to wait for more severe symptoms to appear, such as the patient losing the ability to walk. In general, I can say that the trend is toward stronger medication. But this is always an individual decision, considering the patient’s needs.”

Consider Individual Needs in Treatment

What options are there to tailor treatment to patient needs?
“There are many different options. It is important to discuss the patient’s life situation and future wishes. This involves fundamental questions, such as whether family planning is complete or if there is still a desire for children, especially in the case of young women. Or the professional situation of MS patients. If they travel a lot for work, they may not be able to come to the practice for an infusion every four weeks. In such cases, the method of administration can be adjusted. Besides infusions, there are also injections or tablets. Concerns about side effects also play a role in therapy design and medication selection. Many factors must be considered when choosing the appropriate treatment method. From a medical perspective, it is also about convincing the patient of the necessity of treatment.”

More on the topic

Study on multiple sclerosis Certain vitamin could slow down the onset of MS

Studies on Multiple Sclerosis Unexpected Warning Signs Emerge About 5 Years Before MS Diagnosis

Doctors Often Need to Persuade Patients

Does this mean you sometimes have to convince MS patients of a particular treatment or even treatment in general?
“Yes, definitely. Especially at the beginning. After a relapse, a patient often has no more symptoms. Sometimes someone is symptom-free for one or two years. We, doctors, know that the disease smolders in the background even in phases without pain or other symptoms. This often needs to be explained to patients: Even if they currently have no symptoms, it does not mean the disease is dormant. It is about providing education.”

What exactly do you educate multiple sclerosis patients about?
“I try to convey to patients that there are effective and very well-tolerated medications available today. When I think back to my early days with patients in 1996, research has made great strides. There are entirely new and better treatment options. This is also reflected in current studies: Patients treated today have a much better course than those treated 30 years ago. This is due to a variety of possible medications, which also allow for a change if the current medication does not have the desired effect. In the past, due to a lack of options, one often had to stick with a treatment even if it was ineffective. Today, we can better respond to situations and developments. The earlier diagnosis and early treatment with stronger medications are also significant. Therefore, it can be said that multiple sclerosis has lost some of its terror over the decades.”

Monitoring the Disease Course

Are there patients who refuse to be convinced and treated? How do you handle such cases?
“Yes, such cases exist, of course. It is always the individual’s decision, which I believe should be accepted by the healthcare provider. I offer to accompany the patient on this path as well. An exact documentation of the disease course should still be carried out. A new method here is, for example, special blood tests. In such cases, we also perform an MRI every six months to detect disease activity. If this follow-up examination shows new sites, I seek another conversation with the patient. I then try to convey the benefits of medication on the further course of the disease.”

Lifestyle Adjustments

Are there lifestyle changes you recommend to MS patients?
“Absolutely, it involves the previously mentioned lifestyle factors that are being researched as possible contributors to the disease. It is clear that they negatively influence the course of an existing MS disease. For example, one should stop smoking and follow a low-salt (presumably anti-inflammatory) diet. In our practice, we try to provide information beyond the basics: We offer nutritional counseling and provide recommendations for regular physical activity. It is also important to us to inform women about MS and pregnancy. Additionally, I find it important to pass on new research findings, such as the significance of adequate vitamin D supply for MS patients, which was highlighted about ten years ago.”

You mentioned exercise as part of MS therapy. How important is exercise? And can people who were active before the diagnosis continue their sports as usual?
“Exercise is known to be health-promoting and can protect against various diseases or slow their progression. This applies to cancer, Parkinson’s, and even dementia. The same is true for multiple sclerosis. Therefore, exercise is a clear recommendation for MS patients. Those who were already active before the diagnosis should continue. Initially, there are no restrictions to fear. Patients can often continue their sports as usual for many years, contributing to a more favorable course of their disease.”

Possible Effects on Mental Health

What effects can the diagnosis of MS and living with the disease have on the mental health of those affected?
“The diagnosis is usually a shock at first. Many associate this disease with a life in a wheelchair. Here, it is our task as doctors to clarify that MS is not a disease that necessarily leads to severe disabilities. It is important to alleviate fears and provide patients with a perspective. However, there are also patients who still develop fears and require psychotherapeutic treatment to learn to cope with the disease.”

Learning to cope with the disease, what does that mean?
“For many, the uncertainty of not knowing when the next symptoms will appear is burdensome. Especially at the beginning, many patients worry about unclear symptoms, fearing they might be a new relapse. Additionally, they do not yet know their disease and the associated symptoms well enough. We try to help by taking all concerns and even mild symptoms seriously and always clarifying whether there is a connection with MS.”