TITLE:
Risk factors for internal anal sphincter dysfunction in Japanese adults
AUTHORS:
Tatsuya Abe, Toru Kono, Yoshikazu Hachiro, Masao Kunimoto, Hiroyuki Furukawa
KEYWORDS:
Fecal Incontinence; Internal Anal Sphincter; Anorectal Manometry; Maximal Resting Pressure
JOURNAL NAME:
Open Journal of Gastroenterology,
Vol.3 No.1,
February
17,
2013
ABSTRACT: Purpose: The internal anal sphincter provides most
of the resting anal tone and is the main muscle responseble for continence.
This study was designed to estimate the prevalence of, and identify risk
factors associated with, internal anal sphincter dysfunction in Japanese
adults. Methods: Anorectal manometry was performed in 1193 women and 1124 men
aged 20 years or older. The maximal resting pressure, measured by a rapid
pull-through technique, was defined as the highest resting pressure recorded.
Internal anal sphincter dysfunction was defined as a maximal resting pressure
less than 30 mmHg. Potential risk factors were assessed through self-reports,
interviews, physical examinations, and medical record reviews. Multivariate
logistic regression analysis was used to identify independent risk factors for
internal anal sphincter dysfunction. Results: Significant differences in maximal resting pressure were seen between women (58.1 ± 24.9 mmHg) and men (68.8 ± 23.5 mmHg, P lence of internal anal sphincter
dysfunction was 10.4% (15.5% in women, 5.1% in men). In a multivariate
logistic regression model, age, mental disease, pelvic organ prolapse repair,
and fecal incontinence were independently associated with a greater risk of internal anal sphincter dysfunction in women and men. Conclusions: Internal anal
sphincter dysfunction is a common problem for women and men. Several of the
identified risk factors are preventable or modifiable, and may direct future
research in fecal incontinence therapy.