Arrhythmias & electrophysiologyCohort study
Obesity Subphenotypes in Atrial Fibrillation
- nationwide atrial fibrillation (AF) cohort
- linked Clinical Practice Research Datalink, Hospital Episodes Statistic, and Office for National Statistics data
Authors' conclusion
In this large, nationwide AF cohort, being underweight at the time of AF diagnosis was associated with higher mortality, whereas being overweight and obese were paradoxically associated with lower all-cause mortality despite increased HF hospitalizations in obese patients.
Study context
- Population
- Adults with newly diagnosed AF (1998–2016) and a body mass index (BMI) measure within 12 months of diagnosisadults with newly diagnosed AF
- Participants
- 71,519 adults
- Exposure
- BMI categories vs normal weight
- Outcome
- All-cause mortality
- Follow-up
- Median 5.72 years
Main finding
As reported in the abstract
Each group vs normal weightHazard ratio (95% CI)
underweighthigher mortality with underweight
1.87(1.77–1.96)
overweightlower mortality with overweight
0.72(0.70–0.74)
obeselower mortality with obese
0.69(0.67–0.71)
- Patients who died
- 32,198 patients (45.0%)
Observational data: associations, not effects.
Secondary outcomes
Baseline characteristics
- Mean age
- 74.9 ± 11.3 years
- Females
- 44.9%
Heart failure (HF) hospitalization
- Obesity independently associated with increased HF hospitalization risk, whereas overweight was modestly protective
Myocardial infarction, bleeding and ischemic stroke hospitalization
- Obesity associated with lower adjusted myocardial infarction and bleeding hospitalization and no significant adjusted association with ischemic stroke
Cause-specific mortality
- Higher circulatory and neoplasm deaths among obese patients and higher respiratory deaths in underweight patients
Original publication
Obesity Subphenotypes in Atrial Fibrillation. JACC Adv. Published 5 August 2026. doi:10.1016/j.jacadv.2026.103103
Summarised from the published abstract; every number is checked against it