The push for ever-narrower definitions rests on a
seductive logic: identify the ‘true’ ME patient, and research will finally yield
answers. Reality, however, refuses to cooperate.

I know this field from both sides. After a severe bout
of pneumonia, I became so unwell that I lost my functional capacity and was
eventually labeled with ME (G93.3). 

Today, I conduct research on several
thousand patients with persistent physical symptoms. These experiences point
toward the same conclusion: patient suffering cannot be forced into increasingly
cramped diagnostic boxes.

When the whole body is examined

One of the world’s most comprehensive ME studies
presents a troubling picture [1]. More than 75
researchers examined patients from head to toe, mapping the immune system,
brain, metabolism, muscles, and nervous system. Hundreds of individuals with an
ME diagnosis, or suspected ME, were evaluated.

After a full medical review, only 17 individuals met
the strictest ME criteria.

These numbers conceal a serious consequence. Several
patients were found to have entirely different explanations for their symptoms,
including cancer. A Norwegian study confirms this pattern [2]. After
thorough hospital assessment of hundreds of patients, the majority received
different diagnoses.

This points to a fundamental problem. The symptoms we
call ME encompass a highly heterogeneous group of patients. The risk is
diagnostic overshadowing. We overlook treatable conditions because we are too
quick to apply the ME label, or because we fail to follow up those who already carry
it.

But what did the researchers find in those who
actually met the criteria?

No biological explanation. No clear disease mechanism.
No test that could confirm a diagnosis. They identified non-specific
abnormalities, but the most salient findings were in the brain. 

Patients
reported less energy, and the brain engaged the ‘brake’ more quickly during
exertion, a pattern also found in other studies [3]. In
practice, the researchers found exactly what they started with: the symptoms
themselves.

Patients do not fit into a single box

Clinical data confirm what physicians see every day.
Fatigue rarely occurs in isolation [4]. Patients
often carry a heavy load of pain, sleep problems, and life stressors [5]. Symptoms emerge
from the whole body at once, not just from a single organ [6].

A central symptom in this debate is ‘PEM’, or post-exertional
malaise. It is often presented as proof that ME is a unique biological disease.
The reality is different. PEM is reported across a range of conditions,
including fibromyalgia [7-9], depression,
and even in healthy individuals [10].

Recent data show that as many as 60 per cent of patients with
health anxiety report the same phenomenon. PEM is defined and measured
primarily through patients’ subjective reports. Even when researchers test
patients on exercise bikes in laboratory settings, they find no clear
biological marker that distinguishes ME from other conditions.

In practice, syndrome diagnoses such as ME and
fibromyalgia overlap substantially [9, 11]. Patients fall
along a spectrum of overall burden, not in separate, closed categories [12].
It is the total burden of their symptoms that explains why everyday life grinds
to a halt [5, 13], not the
label written in the medical record.

Diagnoses without a gold standard

ME, fibromyalgia, and chronic pain conditions differ
from many other diseases. They cannot be confirmed by blood tests or imaging.
These diagnoses rest entirely on the patients’ own descriptions and on criteria
established by a limited professional community [14-16].

The boundaries between these diagnoses are so fluid [17]
that the same patient often moves between different labels. Everything depends
on which symptoms are emphasised when the diagnosis is made [18, 19].

Physicians find themselves caught in a professional tug-of-war
[20]. As a
result, two patients with identical symptoms may leave the same clinic with entirely
different diagnoses, simply because they met two different doctors [21]. 

The
diagnosis becomes a sorting mechanism for symptoms [18] – not an explanation of what is actually
happening in the body.

When the diagnosis becomes the problem

One might assume that a diagnosis provides decisive
information. In truth, the label itself says little about the underlying
biology. It is the overall extent of the symptoms that drives the risk of
disability and costs [22], not the
name of the syndrome.

Yet the label carries a more troubling consequence.
Studies suggest that patients diagnosed with ME have a poorer prognosis than
those with identical symptoms who receive a different diagnosis [23]. 

This
paradox demands attention. The cultural expectations and the pervasive illness
narrative surrounding ME may, in themselves, become barriers to recovery.

When the debate is shaped by a desire to isolate ME as
a distinct disease, the consequences are serious. People are not passive
recipients of information [24]. When
patients are told that activity is dangerous and that the outlook is bleak, it
affects how the brain interprets signals from the body [25].

Expectations can generate pain, fatigue, and sleep
problems, as well as biological responses. Even asking people about symptoms
more frequently can lead them to report more symptoms [26]. The advice
to be cautious about activity is intended to protect, but the effect may be the
opposite. Symptoms are amplified and become entrenched.

From label to coping

My experience as a patient taught me how profoundly
disabling these symptoms can be. As a researcher, I have come to see that the
solution does not lie in narrower diagnostic boundaries [27].

We know that even the most severely affected – those
who have lain in darkened rooms, unable to take in nourishment – can recover [28]. What those
of us who found a way out had in common was a fundamental shift in how we
understood and responded to our symptoms.

Patients do not need a stronger illness identity [29]. They need
accurate knowledge about what actually drives recovery, and genuine hope that
change is possible. For the healthcare system, this requires a shift in focus:
away from diagnostic labels and toward function, coping, and the gradual restoration
of tolerance.

When the world’s most comprehensive investigations
fail to identify a single biological cause, the conclusion points in one
direction. ME is not an isolated island in medicine. It is a complex condition
that demands a holistic approach. The crucial question is not which label the
patient carries. It is how we help people reclaim their lives.

(Conflict of interest: Live Landmark is a participant in the Oslo Chronic Fatigue Network. She holds a secondary position in her own company, where she is – among other things – an instructor in the Lightning Process course. Landmark is a former patient diagnosed with post-viral fatigue syndrome/ME.)

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