TY - JOUR
T1 - Phenotypic variation in functional disorders of defecation
AU - Bharucha, Adil E.
AU - Fletcher, Joel G.
AU - Seide, Barb
AU - Riederer, Stephen J.
AU - Zinsmeister, Alan R.
N1 - Funding Information:
Supported in part by US Public Health Service/National Institutes of Health grants R01 HD38666 and R01 HD41129 and by General Clinical Research Center grant RR00585 from the National Institutes of Health in support of the Physiology Laboratory and Patient Care Cores.
PY - 2005/5
Y1 - 2005/5
N2 - Background & Aims: Although obstructed defecation is generally attributed to pelvic floor dyssynergia, clinical observations suggest a wider spectrum of anorectal disturbances. Our aim was to characterize phenotypic variability in constipated patients by anorectal assessments. Methods: Anal pressures, rectal balloon expulsion, rectal sensation, and pelvic floor structure (by endoanal magnetic resonance imaging) and motion (by dynamic magnetic resonance imaging) were assessed in 52 constipated women and 41 age-matched asymptomatic women. Phenotypes were characterized in patients by principal components analysis of these measurements. Results: Among patients, 16 had a hypertensive anal sphincter, 41 had an abnormal rectal balloon expulsion test, and 20 had abnormal rectal sensation. Forty-nine patients (94%) had abnormal pelvic floor motion during evacuation and/or squeeze. After correcting for age and body mass index, 3 principal components explained 71% of variance between patients. These factors were weighted most strongly by perineal descent during evacuation (factor 1), anorectal location at rest (factor 2), and anal resting pressure (factor 3). Factors 1 and 3 discriminated between controls and patients. Compared with patients with normal (n = 23) or reduced (n = 18) perineal descent, patients with increased (n = 11) descent were more likely (P ≤. 01) to be obese, have an anal resting pressure >90 mm Hg, and have a normal rectal balloon expulsion test result. Conclusions: These observations demonstrate that functional defecation disorders comprise a heterogeneous entity that can be subcharacterized by perineal descent during defecation, perineal location at rest, and anal resting pressure. Further studies are needed to ascertain if the phenotypes reflect differences in the natural history of these disorders.
AB - Background & Aims: Although obstructed defecation is generally attributed to pelvic floor dyssynergia, clinical observations suggest a wider spectrum of anorectal disturbances. Our aim was to characterize phenotypic variability in constipated patients by anorectal assessments. Methods: Anal pressures, rectal balloon expulsion, rectal sensation, and pelvic floor structure (by endoanal magnetic resonance imaging) and motion (by dynamic magnetic resonance imaging) were assessed in 52 constipated women and 41 age-matched asymptomatic women. Phenotypes were characterized in patients by principal components analysis of these measurements. Results: Among patients, 16 had a hypertensive anal sphincter, 41 had an abnormal rectal balloon expulsion test, and 20 had abnormal rectal sensation. Forty-nine patients (94%) had abnormal pelvic floor motion during evacuation and/or squeeze. After correcting for age and body mass index, 3 principal components explained 71% of variance between patients. These factors were weighted most strongly by perineal descent during evacuation (factor 1), anorectal location at rest (factor 2), and anal resting pressure (factor 3). Factors 1 and 3 discriminated between controls and patients. Compared with patients with normal (n = 23) or reduced (n = 18) perineal descent, patients with increased (n = 11) descent were more likely (P ≤. 01) to be obese, have an anal resting pressure >90 mm Hg, and have a normal rectal balloon expulsion test result. Conclusions: These observations demonstrate that functional defecation disorders comprise a heterogeneous entity that can be subcharacterized by perineal descent during defecation, perineal location at rest, and anal resting pressure. Further studies are needed to ascertain if the phenotypes reflect differences in the natural history of these disorders.
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U2 - 10.1053/j.gastro.2005.03.021
DO - 10.1053/j.gastro.2005.03.021
M3 - Article
C2 - 15887104
AN - SCOPUS:19044372135
SN - 0016-5085
VL - 128
SP - 1199
EP - 1210
JO - Gastroenterology
JF - Gastroenterology
IS - 5
ER -