Anal sphincter structure and function relationships in aging and fecal incontinence.

Abstract

The objective of the study was to determine the effect of aging and continence status on the structure and function of the external (EAS) and internal (IAS) anal sphincters Young (YC) and older (OC) continent women were compared with older women with fecal incontinence (OI). Patients completed the Fecal Incontinence Quality of Life and Fecal Incontinence Severity Index and underwent anorectal manometry and transanal ultrasound. Nine YC, 9 OC, and 8 OI women participated. Aging was associated with a thickening of the IAS. Older incontinent women had a thinner EAS, had decreased maximum squeeze pressures, and were hypersensitive to rectal distention with decreased tolerable rectal volumes and urge to defecate at lower volumes. Thickening of the IAS occurs with aging. Thinning of the EAS and a corresponding drop in squeeze pressure correlated with fecal incontinence but not aging. Rectal hypersensitivity was associated with fecal incontinence rather than aging and may play a role in the mechanism of fecal incontinence.