Relationships between fatigue, cognitive function, and upright activity in a randomized trial of oxaloacetate for myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Background: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating condition characterized by fatigue, cognitive impairment, and reduced physical function. Oxaloacetate (OAA), a metabolic compound with potential mitochondrial and neuroprotective effects, has shown promise in reducing fatigue symptoms in ME/CFS. However, the interrelationships between fatigue, cognitive performance, and physical activity and their responsiveness to treatment remain poorly understood in ME/CFS.

Methods: This 90-day randomized, double-blind, controlled trial evaluated the effects of 2,000 mg/day OAA or a control of 2,000 mg rice flour in 82 adults with ME/CFS. Self-reported fatigue (Chalder Fatigue Questionnaire), cognitive function (DANA Brain Vital), and upright activity time (UP Time) were assessed at baseline and three follow-up visits. Linear mixed-effects models examined associations between fatigue severity and cognitive/physical function, with treatment group interactions. Responder status at the last visit (Visit 4) was classified based on ≥15% fatigue reduction and/or ≥10% cognitive improvement.

Results: The OAA group showed greater cognitive improvement over time, with a significant between-group difference at Visit 3, 60 days into the trial, (p = 0.034) and trends at other visits. Higher fatigue was significantly associated with reduced cognitive gains in the OAA group (β = −0.34, p < 0.0001), but not in controls. UP Time increased modestly in the OAA group, reaching significance at Visit 2, day 30 (p = 0.044), though fatigue was not a strong predictor of UP Time in either group. At Visit 4, day 90, Global and Fatigue Only Responders were more frequent in the OAA group, while Cognitive Only Responders were more frequent in controls, though group differences did not reach statistical significance (p = 0.10).

Conclusion: OAA supplementation was associated with improved cognitive performance and small improvement in UP Time in ME/CFS participants receiving OAA. Fatigue–cognition coupling was particularly strong in OAA-treated participants, suggesting a potentially targetable phenotype. These findings underscore the importance of multidimensional outcome measures in ME/CFS clinical trials and support the need for more research and trials of metabolic interventions in ME/CFS.

Source: Vernon Suzanne D. , Rond Candace , Sun Yifei , Roundy Shad , Bell Jennifer , Rond Bella , Kaufman David L. , Cash Alan B. , Yellman Brayden , Bateman Lucinda. Relationships between fatigue, cognitive function, and upright activity in a randomized trial of oxaloacetate for myalgic encephalomyelitis/chronic fatigue syndrome. Frontiers in Neurology, Volume 16 – 2025. DOI=10.3389/fneur.2025.1691147 ISSN=1664-2295 https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2025.1691147/full (Full text)

RESTORE ME: a RCT of oxaloacetate for improving fatigue in patients with myalgic encephalomyelitis/chronic fatigue syndrome

Background: The energy metabolite oxaloacetate is significantly lower in the blood plasma of ME/CFS subjects. A previous open-label trial with oxaloacetate supplementation demonstrated a significant reduction in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)-related fatigue.

Methods: In this follow-up trial, 82 ME/CFS subjects were enrolled in a 3-month randomized, double-blinded, controlled study, receiving either 2,000 mg of oxaloacetate or control per day. The primary endpoints were safety and reduction in fatigue from baseline. Secondary and exploratory endpoints included functional capacity and general health status.

Results: Anhydrous enol-oxaloacetate (oxaloacetate) was well tolerated at the tested doses. Oxaloacetate significantly reduced fatigue by more than 25% from baseline, while the control group showed a non-significant reduction of approximately 10%. Intergroup analysis showed a significant decrease in fatigue levels in the oxaloacetate group (p = 0.0039) with no notable change in the control group. A greater proportion of subjects in the oxaloacetate group achieved a reduction in fatigue greater than 25% compared to the control group (p < 0.05). Additionally, 40.5% of the oxaloacetate group were classified as “enhanced responders,” with an average fatigue reduction of 63%. Both physical and mental fatigue improved with oxaloacetate supplementation.

Conclusion: Oxaloacetate is well tolerated and effectively helps reduce fatigue in ME/CFS patients.

Clinical trial registration: https://clinicaltrials.gov/study/NCT05273372.

Source: Alan B. Cash, Suzanne D. Vernon, Candace Rond, Saeed Abbaszadeh, Jen Bell, Brayden Yellman, Lucinda Bateman, David Kaufman. RESTORE ME: a RCT of oxaloacetate for improving fatigue in patients with myalgic encephalomyelitis/chronic fatigue syndrome. Front. Neurol., 26 November 2024. Sec. Experimental Therapeutics. Volume 15 – 2024 | https://doi.org/10.3389/fneur.2024.1483876 https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2024.1483876/full (Full text)