Relationships between fatigue, cognitive function, and upright activity in a randomized trial of oxaloacetate for myalgic encephalomyelitis/chronic fatigue syndrome. — CFSMEATLAS
Relationships between fatigue, cognitive function, and upright activity in a randomized trial of oxaloacetate for myalgic encephalomyelitis/chronic fatigue syndrome.
Vernon, Suzanne D, Rond, Candace, Sun, Yifei et al. · Frontiers in neurology · 2025 · DOI
Quick Summary
This study tested whether a compound called oxaloacetate (OAA) could help people with ME/CFS feel less fatigued and think more clearly. Over 90 days, people taking OAA showed better cognitive improvement and slightly more ability to stay upright compared to those taking a placebo. The results suggest that fatigue and thinking problems are closely linked in ME/CFS, and treating one may help improve the other.
Why It Matters
This study is important because it examines how fatigue, cognitive dysfunction, and physical activity interconnect in ME/CFS—three hallmark symptoms that profoundly impact quality of life. By testing a metabolic intervention and demonstrating differential treatment responses, the research supports the exploration of targeted metabolic approaches and highlights the need for multidimensional outcome measures in future ME/CFS trials.
Observed Findings
Oxaloacetate group showed significantly better cognitive improvement at day 60 (p=0.034) compared to placebo
Upright activity time increased significantly in the OAA group at day 30 (p=0.044)
Higher baseline fatigue was strongly associated with reduced cognitive gains in OAA-treated participants (β=-0.34, p<0.0001) but not in controls
At day 90, Global and Fatigue-Only Responders were more common in the OAA group, while Cognitive-Only Responders were more common in controls (p=0.10)
Oxaloacetate supplementation produced modest improvements in multiple dimensions (cognition, activity, fatigue) compared to placebo
Inferred Conclusions
Oxaloacetate may have metabolic and neuroprotective effects that preferentially improve cognitive function in ME/CFS patients
The strong coupling between fatigue and cognitive gains in OAA-treated participants suggests a targetable phenotype that warrants further investigation
Multidimensional assessment of fatigue, cognition, and physical activity is essential for detecting treatment effects in ME/CFS that single-outcome measures might miss
Metabolic interventions represent a promising avenue for ME/CFS research despite the current modest effect sizes
Remaining Questions
What This Study Does Not Prove
This study does not prove that oxaloacetate is an effective treatment for ME/CFS, as the responder rate differences did not achieve statistical significance and effect sizes were modest. It also does not establish mechanisms by which OAA may work or whether the observed fatigue-cognition coupling is causal versus correlational. The small sample size and short 90-day duration limit generalizability and long-term conclusions.
What is the mechanism by which oxaloacetate improves cognitive function and upright activity in ME/CFS?
Do the cognitive and activity improvements persist beyond 90 days, and what is the optimal dosing and duration of treatment?
Why does fatigue-cognition coupling occur specifically in OAA-treated participants, and can this interaction be used to identify responders prospectively?
What are the longer-term safety and efficacy profiles of oxaloacetate in ME/CFS, and how do effects compare to other metabolic or mitochondrial-targeting interventions?