Researchers Identify Early Diagnostic Patterns Before ME/CFS Diagnosis in Children & Young People

New research published in Scientific Reports has identified patterns of medical diagnoses that commonly appear in the year before a formal diagnosis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) in children and young people.

The large German study suggests that certain symptoms and conditions—ranging from fatigue and pain disorders to post-COVID illness—may serve as early indicators of ME/CFS, potentially helping clinicians recognize the condition sooner.

A Large-Scale Real-World Data Study

The study, titled “ICD-10 Diagnoses prior to ME/CFS diagnosis in children and young people suggest potential early diagnostic indicators,” analyzed health insurance data from more than 7 million individuals aged 6–27 years.

Researchers identified 6,077 young people who were newly diagnosed with ME/CFS between 2020 and 2022. Each case was matched with five similar individuals without ME/CFS to compare which medical diagnoses were documented in the year prior.

Most of those diagnosed were:

Female

Between 18–24 years old

Diagnosed in 2022, reflecting a rise in awareness following the COVID-19 pandemic

What Conditions Appeared Before ME/CFS?

Researchers found 48 diagnostic categories that were significantly associated with a later ME/CFS diagnosis.

The most common patterns appeared in three major areas:

Mental and behavioral health

Respiratory illnesses

Musculoskeletal conditions

Frequently Recorded Diagnoses

Among the most common diagnoses in the year before ME/CFS were:

Fatigue (strongly associated)

Pain disorders

Depression

Somatoform disorders (physical symptoms without a clear medical explanation)

Upper respiratory infections

Laboratory testing and repeated medical consultations

Fatigue stood out as one of the strongest predictors—unsurprising given that it is a hallmark symptom of ME/CFS.

Pain disorders and irritable bowel syndrome were also common, reflecting the overlapping symptom patterns seen in ME/CFS and other functional or chronic pain conditions.

Strong Associations with Fibromyalgia and Cognitive Impairment

Although less common, some diagnoses showed particularly strong associations with later ME/CFS:

Fibromyalgia

Mild cognitive impairment

Neurasthenia

Sleep disorders

These findings reinforce the neurological and systemic nature of ME/CFS and the cognitive difficulties frequently reported by patients.

COVID-19 and Post-Viral Illness

Importantly, several COVID-related diagnostic codes were linked to later ME/CFS.

The strongest association was seen with:

Post-COVID-19 condition (Long COVID) — nearly four times higher odds of a later ME/CFS diagnosis.

COVID testing and COVID-related medical documentation were also more common among those later diagnosed with ME/CFS.

At the same time, prior routine vaccinations in general were not associated with increased risk—and in some cases were negatively associated—supporting existing evidence that vaccines themselves are not a driver of ME/CFS.

What This Means

ME/CFS remains a complex and often delayed diagnosis. There is no single biomarker, and symptoms overlap with many other conditions.

This study suggests that in the year before diagnosis, patients often experience:

Repeated fatigue complaints

Pain and musculoskeletal issues

Cognitive symptoms

Post-viral illness

Increased healthcare utilization

Some of these may represent:

Early manifestations of ME/CFS

Overlapping conditions

Misdiagnoses

Or comorbid illnesses

The researchers emphasize that these findings show association—not causation. More prospective studies are needed to determine whether these diagnoses are true early warning signs or part of a broader diagnostic journey.

Why Earlier Recognition Matters

For many patients, ME/CFS diagnosis can take years. Earlier identification could:

Reduce unnecessary testing

Prevent mislabeling of symptoms

Improve care coordination

Allow for earlier pacing and symptom management strategies

As awareness of ME/CFS grows—particularly in the wake of COVID-19—studies like this help clarify real-world diagnostic patterns and may support improved clinical recognition.

The full study is available in Scientific Reports.