Arrhythmias & electrophysiologyCohort study
Bleeding and New Malignancy Diagnoses After Anticoagulation for Atrial Fibrillation: A Population-Based Cohort Study
- Population-based cohort study
- linked administrative data sets
- bleeding as time-varying covariate
- cause-specific regression models
Authors' conclusion
In anticoagulated patients with AF, bleeding was strongly associated with new cancer diagnoses. Antecedent bleeding was associated with cancer diagnosis at an earlier stage.
Study context
- Population
- People ≥66 years newly initiating warfarin or DOACs after atrial fibrillation (AF) diagnosis, 2008–2022; excluded valvular disease, chronic dialysis, VTE, previous cancer or previously documented bleedingmean age 77.4 y
- Participants
- 119,480 people
- Exposure
- Bleeding vs no bleeding after starting OAC for AF
- Bleedingn = 26,037
- Outcome
- Incident malignancy
- Follow-up
- 2 years after starting anticoagulation
Main finding
As reported in the abstract
2 years
Hazard ratio
4.0
95% CI 3.8–4.3
Bleeding vs Without bleeding
HR 4.0 (95% CI 3.8–4.3)
- Diagnosed with malignancy within 2 years (all participants)
- 5800 (4.9%)
Observational data: associations, not effects.
Further findings
| Outcome | HR (95% CI) | P value | |
|---|---|---|---|
| Any malignancy, by bleeding site · 2 years — gastrointestinal vs Without bleeding · gastrointestinal bleeds | 5.0 (4.6–5.5) | ||
| Any malignancy, by bleeding site · 2 years — genitourinary vs Without bleeding · genitourinary bleeds | 5.0 (4.4–5.7) | ||
| Any malignancy, by bleeding site · 2 years — respiratory vs Without bleeding · respiratory bleeds | 4.0 (3.5–4.6) | ||
| Any malignancy, by bleeding site · 2 years — intracranial vs Without bleeding · intracranial bleeds | 1.8 (1.4–2.2) | ||
| Any malignancy, by bleeding site · 2 years — nasopharyngeal vs Without bleeding · nasopharyngeal bleeds | 1.5 (1.2–2.0) | ||
| 0.20.5125Hazard ratio (log scale) |
| Outcome | Bleeding | Without bleeding | HR | P value |
|---|---|---|---|---|
| Cancers concordant with bleeding site — gastrointestinal vs Without bleeding | 15.4 | |||
| Cancers concordant with bleeding site — genitourinary vs Without bleeding | 11.8 | |||
| Cancers concordant with bleeding site — respiratory vs Without bleeding | 10.1 | |||
| Stage 4 at cancer diagnosis · earlier stage after bleeding | Not reported in the abstract | 31.3% | P = 0.029 |
- Stage 4 at cancer diagnosis: After bleeding 27.6%
Original publication
Bleeding and New Malignancy Diagnoses After Anticoagulation for Atrial Fibrillation: A Population-Based Cohort Study. Circulation. Published 20 February 2025. doi:10.1161/circulationaha.124.070865
Summarised from the published abstract; every number is checked against it