Clinical Characteristics of Defecation Syncope Compared With Micturition Syncope

Abstract

Defecation syncope (DS) and micturition syncope (MS) are daily excretion-related syndromes that are both classified as situational. However, their clinical features seem to be very different, so the present comparative study aimed to clarify those of DS. The study population consisted of 20 consecutive patients with DS and 37 consecutive patients with MS. The DS patients were significantly older than the MS patients (63+/-15 vs 52+/-17 years, P=0.026). Gender was significantly different (P=0.026): women predominated in the DS group (60%) whereas men more commonly had MS (70%). The diurnal distribution of syncope differed (P=0.0054): 88% of MS episodes occurred between 6 pm and 6 am, whereas DS occurred almost equally throughout the 24 h. Syncope after drinking alcohol was less common with DS (10%) than with MS (60%) (P=0.0003), whereas gastrointestinal tract (GIT) symptoms as a premonitory sign were more common with DS (55%) than with MS (3%) (P<0.0001). Positive responses to head-up tilt testing did not differ between the DS and MS groups. DS tends to occur in elderly women and without any significant daily distribution. Alcohol-related syncope was uncommon in patients with DS, and preceding GIT symptoms may be important as predictors or triggering factors.