Prevalence of faecal incontinence: obstetric and constipation-related risk factors; a population-based study

Patients suffering from faecal incontinence may be reluctant to seek medical advice and the true prevalence is uncertain. The aim of the study was to determine the prevalence of faecal incontinence and to correlate this with possible risk factors.

A standardized questionnaire was posted to 955 subjects randomly selected from a local Sydney electoral role of 68 821 voters.

The response rate was 71% (M:F = 259:359). The overall prevalence of faecal incontinence, defined as answering in the affirmative to at least two of three questions which incorporated stool leakage, wearing a pad because of bowel incontinence and frequent incontinence of flatus, was 15% and was more prevalent in men (20%) than women (11%) (P < 0.015). The prevalence of urinary stress incontinence in women was 31%, and similarly 31% for urge incontinence. In men the prevalence of stress and urge urinary incontinence was 4% and 12%, respectively. Overall, there was a significant association between faecal incontinence and a sensation of incomplete rectal evacuation (P < 0.001), obstructed defaecation (P < 0.001), and subjective patient assessment of being constipated (P < 0.001). In women there was a significant association between faecal incontinence and episiotomy (P < 0.01), forceps delivery (P < 0.01), perineal tears (P < 0.01) and hysterectomy (P < 0.049). There was also a strong association between stress urinary incontinence and parity (P < 0.001), episiotomy (P < 0.001), forceps (P < 0.01), perineal tears (P < 0.01) and hysterectomy (P < 0.003). Using logistic regression models, independent risk factors for faecal incontinence were gender (male, odds ratio (OR) = 3.9, 95% confidence interval (CI) = 2.0-7.5), constipation (OR = 27.1, 95% CI = 12.3-59.5), straining (OR = 0.24, 95% CI = 0.1-0.6) and episiotomy (OR = 2.9, 95% CI = 1.4-6.0).

A higher prevalence of faecal incontinence than previously reported was observed, particularly in males. The prevalence of urinary incontinence was consistent with other studies. Faecal and urinary incontinence are important community health problems in both sexes.