Rhythm control should be started earlier in women vs men

Early initiation of rhythm control for atrial fibrillation (AF) appears to be favourable, but women should start rhythm control treatment earlier than men to get the best possible outcomes, according to a study presented at the annual meeting of the European Heart Rhythm Association (EHRA).

Initiated within a year of AF diagnosis, rhythm control treatment lowered the incidence of the primary composite outcome of cardiovascular death, ischaemic stroke, hospitalization for heart failure, or myocardial infarction, regardless of sex, said one of the investigators Assistant Professor Pil-sung Yang of CHA University, Seongnam, South Korea.

Compared with rate control, rhythm control treatment within 1 year reduced the risk of the primary composite outcome by 21 percent in women (weighted incidence rate, 8.68 vs 10.3 per 100 person-years; hazard ratio [HR], 0.79, 95 percent confidence interval [CI], 0.69–0.90; p<0.001) and by 23 percent in men (weighted incidence rate, 6.33 vs 8.32 per 100 person-years; HR, 0.77, 95 percent CI, 0.67–0.88; p<0.001). [Yang PS, et al, EHRA 2022]

However, the optimal initiation time is not the same for men and women, Yang noted.

For rhythm control to be effective, treatment should be started within 6 months after AF diagnosis in female patients and after 11 months after AF diagnosis in their male counterparts, he added.

Moreover, Yang and colleagues found a sex-specific difference in the optimal timing of rhythm control therapy in terms of individual outcomes. For example, rhythm control therapy effectively reduced hospitalization for heart failure when initiated within 2 months of AF diagnosis in women and within 9 months in men.

On the other hand, rhythm control therapy proved effective for ischaemic stroke prevention when initiated immediately in men and within 11 months in women.

The analysis used data from the Korean National Health Insurance Service database and included 22,635 AF patients treated with rhythm control (antiarrhythmic drugs or ablation) or rate control. The investigators used propensity overlap weighting.

While initiation of rhythm control has been reported to yield positive outcomes in patients with new-onset AF when started early, such as in the pivotal EAST-AFNET 4 trial, the findings of the recent study highlight the importance of a sex-specific approach to early rhythm control therapy, Yang said. [N Engl J Med 2020;383:1305-1316]

Sex-related differences have been found in various aspects of AF, including age at diagnosis, clinical manifestations, management, and prognosis. These dissimilarities, according to Yang and colleagues, may dictate different approaches to management and could translate to differences in outcomes. [J Am Heart Assoc 2022;doi:10.1161/JAHA.121.023055; Circulation 2019;140:e125-e151; Eur Heart J 2020;42:373-498]

Nevertheless, like with other cardiovascular therapies, women tend to be treated more conservatively and less aggressively than male patients, they added. [Heart 2018;104:2010-2017; N Engl J Med 2008;358:2667-2677]