The aim of this study was to investigate the influence of rate control on quality of life (QOL).
The RACE II (Rate Control Efficacy in Permanent Atrial Fibrillation II) trial showed that lenient rate control is not inferior to strict rate control in terms of cardiovascular morbidity and mortality. The influence of stringency of rate control on QOL is unknown.
In RACE II, a total of 614 patients with permanent atrial fibrillation (AF) were randomized to lenient (resting heart rate [HR] <110 beats/min) or strict (resting HR <80 beats/min, HR during moderate exercise <110 beats/min) rate control. QOL was assessed in 437 patients using the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) questionnaire, AF severity scale, and Multidimensional Fatigue Inventory-20 (MFI-20) at baseline, 1 year, and end of study. QOL changes were related to patient characteristics.
Median follow-up was 3 years. Mean age was 68 ± 8 years, and 66% were males. At the end of follow-up, all SF-36 subscales were comparable between both groups. The AF severity scale was similar at baseline and end of study. At baseline and at end of study there were no differences in the MFI-20 subscales between the 2 groups. Symptoms at baseline, younger age, and less severe underlying disease, rather than assigned therapy or heart rate, were associated with QOL improvements. Female sex and cardiovascular endpoints during the study were associated with worsening of QOL.
Stringency of heart rate control does not influence QOL. Instead, symptoms, sex, age, and severity of the underlying disease influence QOL. (Rate Control Efficacy in Permanent Atrial Fibrillation; NCT00392613)