E3 PreliminaryPreliminaryPEM ?ObservationalPeer-reviewedMachine draft
Looking for idiopathic intracranial hypertension in patients with chronic fatigue syndrome.
Higgins, Nicholas, Pickard, John, Lever, Andrew · Journal of observational pain medicine · 2013
Quick Summary
This study looked at whether some ME/CFS patients with severe headaches might actually have a separate condition called idiopathic intracranial hypertension (IIH)—increased fluid pressure around the brain. Researchers tested 20 ME/CFS patients with prominent headaches and found that 8 of them had elevated pressure levels, suggesting they had undiagnosed IIH. This raises the possibility that some people diagnosed with ME/CFS might benefit from testing and treatment for this other condition.
Why It Matters
ME/CFS patients with headaches represent a significant subgroup that may be suffering from an undiagnosed, treatable condition. If IIH occurs in some ME/CFS patients, targeted diagnostic testing and treatment could improve outcomes. This work highlights the importance of thorough investigation in ME/CFS and the potential overlap between different conditions that present with overlapping symptoms.
Observed Findings
- 8 of 20 ME/CFS patients with prominent headaches had CSF opening pressures ≥20 cm H₂O
- 3 patients had pressures ≥25 cm H₂O
- Mean CSF opening pressure was 19 cm H₂O across the study group
- 40% of tested patients showed evidence of elevated intracranial pressure
Inferred Conclusions
- Some patients clinically diagnosed with ME/CFS may have unrecognized idiopathic intracranial hypertension
- The two conditions may be related, though the nature of any relationship remains unclear
- Headache-prominent ME/CFS cases warrant investigation for raised intracranial pressure
Remaining Questions
- What proportion of the broader ME/CFS population has elevated intracranial pressure, not just those with prominent headaches?
- Is elevated intracranial pressure a contributor to ME/CFS symptoms, a separate comorbidity, or unrelated?
- What are the appropriate diagnostic criteria and treatment protocols for ME/CFS patients found to have elevated CSF pressure?
- Do ME/CFS patients with normal CSF pressure have different outcomes or symptom profiles compared to those with elevated pressure?
What This Study Does Not Prove
This study does not prove that IIH causes ME/CFS or vice versa—elevated pressure and ME/CFS could be coincidental findings. The small sample size, lack of control group, and selection of patients with especially prominent headaches limits generalizability to all ME/CFS patients. The study cannot determine what percentage of the overall ME/CFS population might have undiagnosed IIH.
Tags
Symptom:PainFatigue
Biomarker:Neuroimaging
Method Flag:Weak Case DefinitionNo ControlsSmall SampleExploratory Only
Metadata
- PMID
- 36698380
- Review status
- Machine draft
- Evidence level
- Early hypothesis, preprint, editorial, or weak support
- Last updated
- 8 April 2026