THE EFFECT OF BIOFEEDBACK THERAPY (BFT) ON ANAL SPHINCTER AND PUBORECTALIS MUSCLES IN PATIENTS WITH FECAL INCONTINENCE

Background and Aims: Normal values for high resolution manometry (HRM), which is used to diagnose defecatory disorders (DD), are limited.A small proportion of asymptomatic people have a prolonged balloon expulsion time (BET).Our aims were to (i) define normal values for rectoanal HRM pressures, (ii) relationship of these parameters with age and BMI, and (iii) compare rectoanal pressures in asymptomatic women with normal and prolonged BET.Methods: Anorectal pressures were assessed with HRM (Medtronic Inc) during rest, squeeze, and evacuation (before and during rectal distention) in 198 healthy people, including 160 women (age 42 ± 1y; BMI 25.8 ± 0.3, Mean ± SEM) and 38 men (age 39 ± 2 years, BMI 25.6 ± 0.9) who did not have Rome 3 criteria for functional bowel disorders.Data for 62 women have been published (Am J Gastro 2012).Parameters were compared in 139 women with normal and 21 with prolonged (>60s) BET.Associations were evaluated with Spearman rank correlations.Wilcoxon's rank-sum test compared HRM parameters in women with normal and prolonged BET.Results: Data are summarized in Table 1.Age was associated with lower resting pressure and shorter squeeze duration, and (ii) greater rectal pressure and rectoanal gradient during evacuation, in women but not in men.BMI was correlated with greater rectal and anal pressures in women and a greater rectoanal gradient in in men.With one exception, correlations between age and anorectal parameters were not significant in men.Compared to women with a normal BET, women with a prolonged BET had a lower (p<0.01)rectoanal gradient during evacuation (-42 ± 3 vs -59 ± 6 mmHg).Conclusions:The normal values for anorectal pressures measured with HRM were mostly comparable to our previous study.Confirming previous studies, age was associated with more pronounced effects on anal resting than squeeze pressure, and in women than in men.This suggests that in women, age has more pronounced effects on internal than external anal sphincter function.During evacuation also, the rectal pressure and rectoanal gradient were greater in older than younger women.Hence, the 10%tile value for rectoanal gradient during evacuation was -110mmHg in younger and -71mmHg in older women.Only when the gradient is more negative than these values is it abnormal, limiting the utility of HRM for diagnosing DD.BMI is positively correlated with rectal and anal pressures during evacuation in women with a normal BET.A small fraction of healthy asymptomatic women have a prolonged BET and a lower (ie, more negative) rectoanal gradient.These features may reflect asymptomatic pelvic floor dysfunction or the inability to simulate defecation in the lab.These individuals should be excluded when generating normal values for anorectal manometry, as in this study.Normal Values in High Resolution Manometry