Autonomic and cerebrovascular abnormalities in mild COPD are worsened by chronic smoking
Bibliographic record
Abstract
Patients with chronic obstructive pulmonary disease (COPD) may develop hypercapnia and hypoxia, two main determinants of cerebral blood flow. The current authors tested whether cerebrovascular regulation was altered in mild COPD, modified by manoeuvres acutely improving autonomic cardiovascular modulation or influenced by smoking habit. In 15 eucapnic normoxic mild COPD patients (eight smokers) and 28 age-matched controls (14 smokers), midcerebral artery blood flow velocity (MCFV), end-tidal carbon dioxide tension (P(ET,CO2)), arterial oxygen saturation (S(a,O2)), ECG and blood pressure at rest were monitored during progressive hypercapnic hyperoxia, isocapnic hypoxia, slow breathing and oxygen administration. MCFV, arterial baroreflex and dynamic MCFV-blood pressure relationships were compared by phase analysis. COPD and control smokers showed higher MCFV (when corrected for P(ET,CO2)), lower cerebrovascular resistance index and lower sensitivity to hypercapnia than nonsmokers, with equal sensitivity to S(a,O2) and similar phase analysis. Arterial baroreflex was depressed in all COPD patients. Slow breathing and oxygen administration improved baroreflex sensitivity and reduced MCFV in all COPD patients. Patients with mild chronic obstructive pulmonary disease show autonomic dysfunction. Chronic smoking induces cerebral vasodilation and impairs cerebrovascular control. All abnormalities can be partly corrected by improving the cardio- and cerebrovascular autonomic modulation, suggesting that functional autonomic abnormalities are already present at an early stage of disease.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".