Survival Benefit of the Primary Prevention Implantable Cardioverter-Defibrillator Among Older Patients
Bibliographic record
Abstract
BACKGROUND: The impact of patient age on the risks of death or rehospitalization after primary prevention implantable cardioverter-defibrillator (ICD) placement is uncertain. METHODS AND RESULTS: Data from 5 major ICD trials were merged: the Multicenter Automatic Defibrillator Implantation Trial I (MADIT-I), the Multicenter UnSustained Tachycardia Trial (MUSTT), the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II), the Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation Trial (DEFINITE), and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). Median age at enrollment was 62 (interquartile range 53-70) years. Compared with their younger counterparts, older patients had a greater burden of comorbid illness. In unadjusted exploratory analyses, ICD recipients were less likely to die than nonrecipients in all age groups: among patients aged <55 years: hazard ratio 0.48, 95% posterior credible interval 0.33 to 0.69; among patients aged 55 to 64 years: hazard ratio 0.69, 95% posterior credible interval 0.53 to 0.90; among patients aged 65 to 74 years: hazard ratio 0.67, 95% posterior credible interval, 0.53 to 0.85; and among patients aged ≥75 years: hazard ratio 0.54, 95% posterior credible interval 0.37 to 0.78. Sample sizes were limited among patients aged ≥75 years. In adjusted Bayesian-Weibull modeling, point estimates indicate ICD efficacy persists but is attenuated with increasing age. There was evidence of an interaction between age and ICD treatment on survival (two-sided posterior tail probability of no interaction <0.01). Using an adjusted Bayesian logistic regression model, there was no evidence of an interaction between age and ICD treatment on rehospitalization (two-sided posterior tail probability of no interaction 0.44). CONCLUSIONS: In this analysis, the survival benefit of the ICD exists but is attenuated with increasing age. The latter finding may be because of the higher burden of comorbid illness, competing causes of death, or limited sample size of older patients. There was no evidence that age modifies the association between ICD treatment and rehospitalization.
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 | 0.001 | 0.005 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| 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".