Gender difference in subjective symptoms related to paroxysmal atrial fibrillation is also detected in postmenopausal women.
Atrial fibrillation (AF) is well known to be male-dominant. Female sex hormones may be involved, since very few premenopausal women experience AF. However, a possible gender difference in older subjects has not been fully elucidated yet. We retrospectively reviewed the symptoms of 133 patients (111 males and 22 females) with paroxysmal AF (PAF) from the medical records at our hospital from 1995 to 2000, and classified the patients according to the time of the attacks as day type, night type, or unspecific type. In females, the age at the first diagnosis of PAF was significantly higher (males: 57 +/- 1 year old, females: 65 +/- 2 years old; P = 0.006) and the proportion of cases younger than 61 years old was significantly smaller (63%, 32%; P = 0.007). As in previous reports, the female group had more cases with unspecific type (26.5%, 47.6%) or with long duration (> 24 hours) (16.9%, 37.5%). In contrast to these published results, fewer women (10.5%) had frequent attacks (more than twice a week) than men (39.8%). The incidence of regular alcohol consumption, one of the most important PAF triggers, was significantly higher in men than women (84.7%, 13.6%; P < 0.0001). Even when we focused on cases older than 60 years old, the female group still had more cases with unspecific type (53.3% versus 23.1%) or with long duration (27.3% versus 14.7%) than men, and fewer with frequent attacks (0% versus 51.7%) or regular alcohol consumption (6.7% versus 82.9%; P < 0.0001) than men. The gender difference in symptoms related to PAF may depend not only on sex hormones, but also on intrinsic or social gender differences.