Early rhythm control beneficial vs. rate control in AF, but effect may decrease with age
In patients younger than 75 years with atrial fibrillation and concomitant CV conditions, an early rhythm control strategy was associated with better CV outcomes compared with a rate control strategy, researchers reported.
However, the benefits of an early rhythm control strategy were less pronounced in patients aged 75 years or older.
“Early initiation of a rhythm control, compared with a rate control strategy within 1 year of the diagnosis, was associated with less frequent CV events in patients younger than 75 years,” Boyoung Joung, MD, PhD, professor and director of the Heart Rhythm Center and vice president of Severance Hospital, Yonsei University, South Korea, told Healio. “The protective association between early rhythm control and CV outcomes exhibited a linear decrease with advancing age. Although attenuated with increasing age, a trend toward better CV outcomes for early rhythm control was consistently observed without affecting safety outcomes in elderly patients with AF.”
Outcome differences by age
In a retrospective study, Joung and colleagues analyzed data from 31,220 adults with AF undergoing rhythm control with antiarrhythmic drugs or ablation or rate control therapy, using the Korean National Health Insurance Service database. The median age of the cohort was 69 years; median follow-up was 48.9 months. Treatments were initiated within 1 year of an AF diagnosis. Researchers compared risk for a composite outcome of CV death, ischemic stroke, hospitalization for HF or MI between treatment groups, stratified by age.
The findings were published in JACC: Clinical Electrophysiology.
Compared with rate control, early rhythm control was associated with a 20% lower risk for the primary composite outcome in patients younger than 75 years (HR = 0.8; 95% CI, 0.72-0.88; P < .001). For adults younger than 75 years, there was also lower risk for ischemic stroke (HR = 0.79; 95% CI, 0.68-0.9) and admission for HF (HR = 0.79; 95% CI, 0.69-0.9) with early rhythm control compared with rate control.
The protective benefits waned with increasing age; with a 6% lower risk with early rhythm control among adults aged 75 years or older (HR = 0.94; 95% CI, 0.87-1.03; P for interaction = .045). Researchers also observed trends for lower risk for ischemic stroke (HR = 0.79; 95% CI, 0.68-0.9) and acute MI (HR = 0.63; 95% CI, 0.41-0.97) among older adults who underwent early rhythm control. There were no between-group differences in safety outcomes.
“The protective association of early AF rhythm control was attenuated with advancing age,” Joung told Healio. “The benefits for early rhythm control relative to rate control were more prominent in younger patients. These results support more aggressive early rhythm control in younger adults and call for shared decision-making regarding the benefits of early rhythm control therapy in older adults with AF.”
Joung said further research is needed to identify patient populations who are better candidates for the early rhythm control therapy.
“Moreover, we must identify the effect of early rhythm control on individual CV outcomes,” Joung said.
Data ‘support a rhythm control strategy’
In a related editorial, Dominik Beer, DO, an internist at Geisinger Heart Institute in Wilkes Barre, Pennsylvania, and Hugh Calkins, MD, professor of medicine at Johns Hopkins Hospital and past president of the Heart Rhythm Society, called the findings timely and important, despite the limitations of a nonrandomized study.
“We are pleased that in addition to the EAST-AFNET 4 trial, we have additional data supporting the rhythm control strategy,” Beer and Calkins wrote. “Throughout our careers, we have been advocates for sinus rhythm, and thanks to the work of Kim et al, we have more data to support a rhythm control strategy, especially in patients younger than 75 years. The authors are to be congratulated for the considerable time and effort required to carry out and publish these important results.”