Abstract 16923: The Impact of the Publication of Cardiovascular Safety Signals on the Prescribing of Varenicline: an Interrupted Time-Series Analysis
Bibliographic record
Abstract
Introduction: Concerns regarding the cardiovascular safety of varenicline, a smoking cessation drug, arose following the publication of a meta-analysis of randomized controlled trials in July 2011. The impact of this safety signal on the prescribing patterns of varenicline remains unknown. Hypothesis: Our hypothesis was that the reported increased risk of adverse cardiovascular events resulted in a decreased prescription rate of varenicline. Methods: This study was conducted using the Clinical Practice Research Datalink, a large primary care database from the United Kingdom (UK). An interrupted time-series analysis using segmented auto-regression was conducted to compare varenicline prescribing patterns in the pre-publication (January 2007-June 2011) and post-publication (July 2011-December 2012) study periods. The fitted model was used to estimate the predicted rate that would have been observed in the post-publication period in the absence of the published safety signal. Results: In the pre-publication period, the estimated prescription rate of varenicline increased by 27.4 (95% CI = 17.0, 37.7) prescriptions per month per 100,000 person-years (PYs), resulting in a rate of 2,464 prescriptions per 100,000 PYs in June 2011. The safety signal resulted in an estimated drop in the prescription rate of 513.4 (95% CI = -1020.9, -5.9) prescriptions per 100,000 PYs, representing a 21% decrease in the estimated prescription rate (R 2 = 0.82). In the post-publication period, there was a change in direction in the trend, with the prescription rate decreasing by 42.4 prescriptions per month per 100,000 PYs (95% CI = -92.9, 8.1) during this period. The differences between the observed and predicted rates are shown in the Figure. Conclusions: The publication of the meta-analysis suggesting an increased risk of adverse cardiovascular events associated with its use resulted in a significant decrease in the prescription rate of varenicline in the UK.
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 | 0.076 | 0.153 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.008 |
| Bibliometrics | 0.003 | 0.005 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.003 | 0.002 |
| Research integrity | 0.002 | 0.003 |
| Insufficient payload (model declined to judge) | 0.011 | 0.001 |
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".