Clinical and physiological risk factors for fecal incontinence in chronically constipated women

Fecal incontinence (FI) and chronic constipation (CC) are disabling symptoms that cause a significant public health problem. The pathophysiology of combined constipation and FI is not fully understood. Our aim was to delineate the clinical, physiological and anatomical factors that may contribute to the association of FI and CC.

A retrospective study was performed in a pelvic floor unit in a tertiary medical center. Consecutive female patients diagnosed with CC were included, and further divided into two groups according to the co-occurrence of FI. Demographic characteristics, anorectal physiology (obtained by manometry) and pelvic anatomical pathology (as assessed by dynamic pelvic ultrasound) were recorded and subsequently compared.

A total of 267 women were included in the study. Of those, 62 patients (23%) had an associated FI (CCFI). The CCFI group had higher body mass index (BMI) levels and a trend toward younger average age as compared to the group without FI (CCNFI). The number of vaginal and instrumental deliveries was similar in both groups. Anal resting and squeeze pressures were significantly lower in the CCFI group (64 ± 21 vs 48 ± 18, p = 0.004 and 141 ± 136.2 vs. 97.5 ± 38.6, p = 0.02, respectively). Rectal sensation abnormalities were common, but did not differ between both groups. Dyssynergic defecation and rectocele were more common in the CCNFI group (68% vs. 51%, p = 0.04 and 39% vs. 24%, p = 0/045, respectively.

Lower anal pressures and higher BMI were found among women with coexisting FI and CC. Pelvic floor anatomical and functional abnormalities are common in women diagnosed with CC and FI, but dyssynergia and diagnosis of significant rectocele, which cause obstructed defecation, were more common in the CCNFI group.