Effects of Rhythm Control versus Rate Control on Atrial Fibrillation and Frailty Development in Older Patients: Protocol for the Cardioversion of Atrial Fibrillation and Frailty in the Elderly (CAFFE) Study, an Observational, Prospective Cohort Study.

BACKGROUND

Atrial fibrillation (AF), highly prevalent in older individuals, is associated with frailty and disability. AF therapy is based on rhythm control (RhythmC) to restore sinus rhythm or rate control (RateC) to lower the heart rate. Published guidelines do not indicate a preference for one over the other for older people.

OBJECTIVE

This study aims to evaluate whether RhythmC is more effective than RateC in hindering the progression of frailty and disability.

METHODS

The Cardioversion of Atrial Fibrillation and Frailty in the Elderly (CAFFE) study is a prospective, multicenter, observational cohort study that includes 4 groups of patients: (1) adults age 75 years or older undergoing RhythmC treatment; (2) adults aged 65 to 74 years undergoing RhythmC treatment; (3) adults 65 years or older undergoing RateC treatment; and (4) adults 65 years or older without overt chronic conditions as the control group (n=40 in each group). At baseline, all participants will undergo a Comprehensive Geriatric Assessment (CGA) and analyses of inflammation and metabolomics. At home, a device will evaluate each participant's heart rhythm, activity profile, and sleep. After 1 month, the CGA will be repeated.

RESULTS

The CAFFE study was funded as a Research Project of National Interest by the Italian Ministry of University and Research (October 2023). Ethical committee final approval was given in June 2024. In October 2025, the coordinating center had enrolled 31 of 40 patients with AF (mean age 78, SD 9 years; 8 [25.8%] women; mean CHA2DS2-VA score 4.2, SD 1.2; 13 [43.3%] robust participants). All centers are now completing the enrollment (103/160 participants), and the analysis of inflammatory mediators has started. The results are expected to be published in summer 2027.

CONCLUSIONS

The CAFFE study will evaluate the effectiveness of AF management strategies in older patients. If RhythmC can slow the progression of frailty and disability, specific clinical trials should more definitively address this knowledge gap.