CARDIOPULMONARY EXERCISE TEST PERFORMANCE IN MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME: SYSTEMATIC REVIEW AND META-ANALYSIS
Bibliographic record
Abstract
PURPOSE/HYPOTHESIS: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is characterized by a waxing and waning set of disabling symptoms that occur in response to physical activity. Symptomatology is thought to be associated with decremented performance on CPET, however study results have been mixed. The purpose of this systematic review and meta-analysis was to compare CPET performance between individuals with ME/CFS and matched control subjects. NUMBER OF SUBJECTS: Eighteen studies including n = 975 people who met clinical criteria for ME/CFS (eg, Oxford, Holmes, Fukuda, Canadian Consensus Criteria, and International Consensus Criteria) and n = 500 control subjects who were matched for sex and age. MATERIALS AND METHODS: Articles that reported CPET measurements at either peak exertion or ventilatory anaerobic threshold (VAT) were included in the quantitative analysis. Medline Complete, CINAHL, Academic Search Complete, SPORTDISCUS, and PsycINFO was searched on 5 December 2018 using keywords ((SU exercise tests) OR (exercise physiology) OR (cardiopulmonary system)) AND ((SU myalgic encephalomyelitis) OR (SU chronic fatigue syndrome)). Hand searches of the reference sections of identified papers were also completed. The systematic review revealed 18 articles that were included in the quantitative analysis. Measurements of volume of oxygen consumed (VO2), heart rate (HR), workload (WL), respiratory exchange ratio (RER) obtained during a single CPET were abstracted for maximal exertion and VAT. Standardized mean difference (d) and 95% confidence interval (95% CI) were calculated for each variable. Two-sample t test were conducted to assess the statistical significance of raw mean differences between groups. Statistical significance was determined at α ≤ 0.05. RESULTS: Clinical criteria used to identify ME/CFS and ramping protocols varied across studies. No significant difference in maximal RER was identified between groups (d: −.07; 95% CI: −0.20 to 0.06; P = .293). At maximal exertion, significant differences favoring the matched control subjects were identified for VO2 (d: −1.13; 95% CI: −2.16 to −1.01; P < .0001) HR (d: −1.65; 95% CI: −2.11 to −1.52; P < .0001), and WL (d: −4.26; 95% CI: −4.48 to −4.02; P < .0001). Subjects with ME/CFS had higher maximal RPE than matched control subjects (d: 0.93; 95% CI: .55 to 1.29; P < .0001). At VAT, significant differences favoring the matched control subjects were identified for VO2 (d: −1.53; 95% CI: −1.75 to −1.31; P < .0001), HR (d: −2.12; 95% CI: −2.28 to −1.96), and WL (d: −6.50; 95% CI: −6.84 to −6.18). CONCLUSIONS: People with ME/CFS demonstrated lower VO2, HR, and WL at maximal exertion and VAT compared to age and sex matched control subjects. The magnitude of differences between groups was greater at VAT than maximal exertion. CLINICAL RELEVANCE: People with ME/CFS demonstrate objectively verifiable impairments in VO2, HR, and WL on CPET, which may relate to observed functional disability.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.002 | 0.001 |
| Bibliometrics | 0.000 | 0.002 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".