Dihydropyridine calcium channel blockers and the progression of parkinsonism
Bibliographic record
Abstract
OBJECTIVE: A study was undertaken to test the association between dihydropyridine calcium channel blocker use and the time to important milestones of disease progression among patients with parkinsonism. METHODS: Data were obtained from Ontario's health care administrative databases. Within a cohort of hypertensive individuals older than 65 years who developed parkinsonism, we examined the effect of the length of exposure to less brain-penetrant dihydropyridines (amlodipine) and more brain-penetrant dihydropyridines (eg, nifedipine, felodipine) on parkinsonism milestones as measured by time to requiring drug treatment for parkinsonism, nursing home admission, and death. RESULTS: Among 4,733 hypertensive individuals with parkinsonism, longer treatment with any dihydropyridine was associated with a decreased risk of each of the 3 outcomes. There was no difference, however, between amlodipine (adjusted hazard ratio [HR], 0.46; 95% confidence interval [CI], 0.42-0.50 for initiation of drug treatment; HR, 0.68; 95% CI, 0.63-0.73 for application for nursing home admission; and HR, 0.75; 95% CI, 0.70-0.80 for death) and nonamlodipine dihydropyridines (adjusted HRs [95% CIs], 0.45 [0.39-0.53], 0.74 [0.67-0.81], and 0.74 [0.64-0.85] for the 3 milestones, respectively). INTERPRETATION: We found no specific beneficial effect of treatment with brain-penetrant dihydropyridines on delaying parkinsonism progression milestones. Dihydropyridine calcium channel blockers are unlikely to have a clinically significant effect on the course of parkinsonism, particularly Parkinson disease, in the doses used to treat hypertension.
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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 | 0.002 |
| 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 | 0.001 |
| 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".