Weight Loss Does Not Improve Persistent Atrial Fibrillation Symptoms in Older Adults: LOSE-AF Trial
UK: A structured low-calorie diet and behavioral support program led to significant and sustained weight loss in older adults with overweight and persistent atrial fibrillation (AF), but did not improve AF symptoms or reduce the burden of the condition compared with usual care, according to findings from the LOSE-AF randomized clinical trial published in JAMA.
The study was led by Matteo Sclafani from the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK, and colleagues. The researchers noted that while obesity is a well-established risk factor for AF and weight loss is recommended in current clinical guidelines, existing evidence has largely been derived from younger populations. Whether similar benefits extend to older adults has remained uncertain, particularly because weight loss in this age group may increase the risk of frailty.
The multicenter, open-label randomized clinical trial was conducted at two UK hospitals between 2018 and 2025. It enrolled 118 adults aged 60–85 years with persistent atrial fibrillation (AF) and a BMI of at least 27 kg/m², who were randomized to an 8-month low-calorie diet with behavioral support (n=59) or usual care (n=59).
The primary outcome was the change in Atrial Fibrillation Severity Scale (AFSS) symptom score at eight months. Secondary outcomes included AF burden, physical performance, cardiac remodeling, blood pressure, lipid profile, and the need for repeat rhythm-control procedures.
Key findings include:
- The intervention group achieved significantly greater weight loss than the usual care group, with an average weight reduction of 9.7% compared with 3.1%.
- At eight months, participants in the intervention group weighed an adjusted mean of 92.6 kg versus 99.4 kg in the control group, representing an average difference of 6.9 kg.
- Despite the greater weight loss, AF symptom severity did not differ significantly between the two groups.
- The dietary intervention also did not significantly improve AF burden, physical performance, cardiac imaging measures, blood pressure, lipid profile, or the need for repeat cardioversion or AF ablation.
- No serious adverse events related to the intervention were reported, indicating that the weight-loss program was safe in this older population.
The authors noted several limitations, including the open-label design, although blinded outcome assessment helped reduce bias. The COVID-19 pandemic also affected recruitment and limited some secondary assessments. Additionally, the moderate weight loss achieved through diet and lifestyle changes may have been insufficient to influence cardiovascular risk factors or AF outcomes.
Overall, the findings suggest that while a low-calorie diet and behavioral support safely produced significant weight loss in older adults with overweight and persistent AF, it did not improve AF symptoms, reduce arrhythmia burden, or lessen the need for further rhythm-control interventions. The researchers conclude that moderate lifestyle-based weight loss alone is unlikely to be an effective treatment strategy for persistent AF in this population.
Reference:
Sclafani M, Spartera M, Esmati Y, et al. Weight Loss in Older Patients With Persistent Atrial Fibrillation: The LOSE-AF Randomized Clinical Trial. JAMA. 2026;336(3):205–214. doi:10.1001/jama.2026.5787
Next Story