Effect of biofeedback therapy on anorectal physiological parameters among patients with fecal evacuation disorder

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DOI 10.1007/s12664-017-0731-y ORIGINAL ARTICLE Effect of biofeedback therapy on anorectal physiological parameters among patients with fecal evacuation disorder Abhai Verma 1 & Asha Misra 1 & Uday C Ghoshal 1 Received: 25 September 2016 /Accepted: 20 January 2017 # Indian Society of Gastroenterology 2017 Abstract Background Though biofeedback therapy is often effective in patients with fecal evacuation disorder (FED), a common cause of chronic constipation (CC) in tertiary practice, data on anorectal physiological parameters following it are scanty. Methods Consecutive patients with FED with CC diagnosed by abnormalities in at least two of the three tests (anorectal manometry, defecography, and balloon expulsion test [BET]) undergoing biofeedback (two sessions per day, 30 min each, for 2 weeks) during a 3-year period were analyzed. Clinical evaluation, anorectal manometry (ARM), and BET were performed at the beginning and after biofeedback. Results Incomplete evacuation 42/43 (98%), straining 40/43 (93%), and feeling of outlet obstruction 35/43 (81%) were the most common symptoms among these 43 patients (median age 44 years, range 18 76, 30 [71%] male). All the three tests (defecography, BET, and ARM) were abnormal in 17 (40%) patients and the others had two abnormal tests. Improvement in physiological parameters was noted following biofeedback (median residual anal pressure during defecation 99 mmhg (range 52 148) vs. 78 mmhg (37 182), p = 0.03; maximum intra-rectal pressure 60 mmhg (90 110) vs. 76 mmhg (31 178); p = 0.01; defecation index 1.1 (0.1 23.0) vs. 3.2 (0.5 29.0); p = 0.001). Dyssynergia on ARM and BET got corrected in 22/34 (65%) and 18/30 (60%) patients. At a 1- month follow up, 23/37 (62%) patients reported satisfactory symptomatic improvement. Conclusions Biofeedback not only improves symptoms but also anorectal physiological parameters in patients with FED. * Uday C Ghoshal udayghoshal@gmail.com 1 Department of Gastroenterology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow 226 014, India Keywords Anorectal physiology. Chronic constipation. Defecography. Manometry. Treatment Introduction Chronic constipation may be broadly classified into constipation-predominant irritable bowel syndrome (IBS-C) and functional constipation, either of which may be associated with slow colon transit and fecal evacuation disorder (FED) [1, 2]. These disorders often overlap with each other in a variable degree [2, 3]. Unlike slow transit constipation (STC) and IBS-C, in which pharmacotherapy is the cornerstone of management, FED is primarily managed by biofeedback [4]. FED is characterized by either deficient pelvic floor support or abnormal contraction of pelvic muscles [3]. Surgery for structural defects such as rectocele and/or trained coordinated exercise of pelvic muscles are the cornerstone of treatment for FED depending upon the predominant pathophysiology [5]. Biofeedback [6] involves real-time training of coordinated contraction of pelvic muscles and relaxation of anal sphincters to evacuate the rectum. In the process, patient is given live feedback about the status of the rectal emptying and also about coordinated contraction of pelvic muscles and relaxation of anal sphincters. Various studies have shown varied results of biofeedback in patients suffering from FED [7 21]. These studies have wide variations in inclusion and diagnostic criteria of FED, severity of disease, and most importantly the end point of intervention. The objective end point of treatment is difficult to define in FED. Some studies have evaluated complete spontaneous bowel movement (CSBM) per week as the objective end point for biofeedback for FED [2, 19, 20] whereas others have looked at the changes in manometric parameters. In the present study, we have

evaluated the effect of biofeedback therapy on physiological parameters as assessed by manometry in patients with FED. Methods Study protocol Prospectively maintained data of consecutive patients undergoing biofeedback in the Gastrointestinal Pathophysiology and Motility Laboratory in a multi-level teaching hospital in northern India during a 5-year period (June 2010 to June 2015) were retrospectively analyzed. Patients Those presenting with chronic constipation and diagnosed as FED based on standard criteria (Rome III) [22] were included in the study. Patients undergoing major pelvic surgery in the past, reporting active bleeding per rectum, anal fissure, or any major spinal deformity, were excluded. All the patients underwent a flexible sigmoidoscopy to rule out any organic pathology. Other contributing causes of constipation like hypothyroidism, uncontrolled diabetes, and hypercalcemia were also investigated, and patients were excluded if these disorders were not controlled. Information about bowel habit including stool frequency per week, predominant consistency (Bristol scale), straining including its duration, feeling of incomplete evacuation, manual assistance during defecation, and use of enemas and suppositories was collected using a standard questionnaire. Before and after completing all the sessions of biofeedback, patients were asked about overall satisfaction of their bowel habits. Diagnosis of FED FED was diagnosed based on highresolution anorectal manometry, BET, and barium defecogram, which were performed using standard techniques described earlier [3]. Anorectal manometry (ARM) was performed either by water perfusion (G S Hebbard, Australia) or solid-state catheters (Sandhill Scientific, Milwaukee, WI, USA). An abnormal result in any of the three tests, such as anorectal manometry (anal basal sphincter pressure >100 mmhg and/or squeeze pressure >167 mmhg, defecation index DI 1.4), defecography (lack of opening of the anorectal angle by >15 and/or perineal descend 4 or 2 cm rectocele), and BET ( 200 g added weight needed to expel a balloon filled with 50 ml of water), was noted. However, FED was diagnosed according to the Rome III criteria in the presence of chronic constipation and abnormal result in at least two of the above-mentioned three tests [22]. Patients who showed dyssynergic pattern of defecation were classified into four types. Type I is an adequate increase in rectal pressure (>40 mmhg) with paradoxical simultaneous rise in anal pressure, type II is an inadequate increase in rectal pressure (<40 mmhg) accompanied by a paradoxical simultaneous increase in anal pressure, type III is an adequate increase in rectal pressure ( 40 mmhg) accompanied by a failed reduction in anal pressure ( 20% baseline pressure), and type IV is an inadequate increase in rectal pressure of (<40 mmhg) accompanied by a failed reduction in anal pressure ( 20% baseline pressure). Biofeedback protocol Patients who fulfilled criteria for FED and did not respond to standard treatment were treated with biofeedback. Pressure-based visual biofeedback was performed by one of the authors (AM) using water perfused high-resolution manometry system (G S Hebbard, Australia). Each patient underwent two sessions of biofeedback per day (forenoon and afternoon) lasting for 30 min each, for 14 consecutive days. Normal physiology of defecation and the abnormality in the index patient was explained in details before treatment. Biofeedback therapy was performed in the left lateral position. Subject was first asked to take a deep diaphragmatic breath and then pushdown, as one would do during defecation. Immediate feedback, verbal as well as visual as seen on the screen, was given to the subject. Biofeedback therapy was performed with the manometry catheter alone without a balloon, twice daily for about 30 min for 2 weeks. Patients were asked to expel the catheter. During one 30-min session, the push down maneuver with catheter in rectum was done for approximately 10 15 times. No sensory training was given. Patients were given a stool diary and were asked to fill it before and after biofeedback. This diary comprised of important points about bowel habits like frequency, consistency (Bristol scale), straining, feeling of incomplete evacuation, use of manual maneuvers, use of laxatives and enemas, and overall satisfaction. During biofeedback treatment, patients were allowed to take laxatives on demand. Non-pharmacological measures like physical exercise, increased water intake, and high fiber diet were also emphasized upon. Patients were also informed about the value of the use of Indian type toilet and posture. ARM and BET were repeated at the end of the 15-day biofeedback protocol to look for changes in various physiological parameters. Patients undergoing ARM using water perfusion and solid-state catheter were subjected to ARM using the same system after biofeedback. Patients were also asked to report about overall satisfaction in their bowel symptoms at the completion of treatment and at 1 month of follow up. Statistical analysis Data were checked for normal distribution using the Shapiro-Wilk test. Categorical and continuous data were presented as proportion and mean, standard deviation, median, and range depending upon their distribution. Paired continuous data were analyzed using paired t test or Wilcoxon signed-rank test depending on distribution. Categorical variables were analyzed using a chi-square test, with Yates correction as applicable. P-values of <0.05 were considered significant.

Results Patient profile The total number of patients identified during the study period was 43 (median age 44 years, range 18 to 76 years) of which 30 (70%) were males. Median BMI for males and females was 21.7 (17.3 36.0) and 19.9 (16.4 27.3), respectively. Most of them complained about constipation for long duration (median 56 months, range 8 120 months). All patients were euthyroid at the time of biofeedback therapy and their blood sugars were also within normal limits. No patient reported complete relief of symptoms with laxatives. Median stool frequency per week was 14 (range 2 70). The important and characteristic symptoms of FED and their frequency are shown in Table 1. Feeling of incomplete evacuation and straining were the most common symptoms. All the patients fulfilled Rome III criteria for IBS. Eleven (25%) patients reported bleeding per rectum at least once in the last 6 months. On investigation, these patients were found to have either hemorrhoids or solitary rectal ulcer syndrome (SRUS). Although all the patients complained about constipation but when enquired about consistency of stool using Bristol stool chart, only nine (21%) had type 1 3 stools. Diagnosis of FED was made based on the abnormal test results on BET plus ARM in 8 (18%), defecography plus BET in 12 (28%), defecography and ARM in 6 (14%), and on all the three tests in 17 (40%). All the patients completed the above-mentioned biofeedback protocol. ARM and BET was repeated at the end of therapy for all the patients. Anorectal manometry and BET The pre- and postbiofeedback manometric parameters are depicted in Table 2. There was significant reduction in basal sphincter pressure and anal pressure during defecation. Also, the maximal intra-rectal pressure during defecation increased significantly after biofeedback (Fig. 1). There was no difference in the sensory parameters following biofeedback. Defecation index (DI), defined as ratio of maximum intra-rectal pressure during defecation to residual anal pressure, was calculated and values 1.4 were considered as abnormal [23, 24]. It is an important parameter as values of >1.4 are needed for normal defecation. Therefore, improvement in DI translates into better relief of Table 1 Clinical spectrum of patients with fecal evacuation disorder Symptom Number (%) Stool consistency Bristol 1 3 9 (21%) Bristol 4 8 (19%) Bristol 5 7 26 (60%) Straining 40 (93%) Incomplete evacuation 42 (98%) Outlet obstruction 35 (81%) Manual assistance 16 (37%) symptoms. Median pre-biofeedback DI was 1.1 (range 0.1 to 23.0), which improved to 3.3 (range 0.5 to 29; p-value = 0.001) after biofeedback (Fig. 2). BET normalized from 7/43 (16.2%) to 18/37 (48.6%) of patients after biofeedback (p = 0.004).We classified all the patients into various types of dyssynergia and found that type I dyssynergia was commonest (Fig. 3). Due to small numbers of patients classified into other types of dyssynergia, they were grouped into a single group (non-type I). Overall dyssynergia was reversed in 32/43 (74%) patients (20/26 in type I and 14/17 in non-type I; p =0.6). Follow up On follow up (available in 37, 83% patients), straining (40/43 vs. 10/37, p=0.001), incomplete evacuation (42/43 vs. 18/37, p=0.002), outlet obstruction (35/43 vs. 4/37, p=0.001), and manual assistance for defecation (16/43 vs. 3/37, p=0.002) improved at 1-month. Overall satisfaction regarding bowel symptoms at 1 month was found to be 23/37 (62%). Discussion The present study shows the beneficial effects of biofeedback on objective physiological parameters in patients with FED. Most of the important parameters, which were abnormal in FED, like dyssynergic pattern, basal and residual sphincter pressures, and intra-rectal pressure during defecation and abnormal balloon expulsion test improved with biofeedback. There is paucity of data about FED and biofeedback therapy for this group of disorder from India. Our study is the first one from the country showing efficacy of biofeedback therapy on physiological parameters in patients with FED. In a recent study from India, Shah et al. [2] reportedthat 40% of all the subjects with primary constipation were having dyssynergic defecation (DD) on ARM. The clinical efficacy of biofeedback in this study was 70% as judged by complete spontaneous bowel movement (CSBM). However, only 20 patients completed more than four sessions of biofeedback. Moreover, ARM was not repeated at the end of biofeedback; so changes in objective physiological parameters could not be ascertained. In the present study, we have used a more stringent biofeedback protocol and also demonstrated improvement in physiological parameters at the end of this protocol. Rao et al. [20] compared the biofeedback therapy with the sham feedback in patients with DD. This is the only randomized controlled trial available in the literature comparing biofeedback with sham feedback therapy and standard therapy. Although in this study the number of CSBMs per week did improve significantly with biofeedback, global bowel satisfaction score showed no significant improvement when compared to standard therapy. They also showed improvement in all the motor and sensory physiological parameters as assessed by anorectal manometry. In the present study, we

Table 2 Effect of biofeedback on anorectal parameters Parameter Pre-biofeedback Post-biofeedback p-value Basal sphincter pressure (mmhg) 77 (52 128) 71 (42 105) 0.01 Squeeze pressure (mmhg) 167 (75 248) 141 (81 246) 0.22 Anal pressure during defecation (mmhg) 99 (52 148) 78 (37 182) 0.03 Intra-rectal pressure during defecation (mmhg) 60 (9 110) 76 (31 178) 0.01 Balloon distension first sensation (cc) 40 (20 80) 40 (20 250) 0.66 Balloon distension urge to defecate (cc) 100 (40 200) 100 (60 250) 0.73 Balloon distension pain (cc) 250 (80 400) 250 (80 400) 0.39 have not included any sham therapy but improvement in pressure parameters is almost similar. In a study by Chiaroni et al. [9], biofeedback was compared to laxatives in patients with FED. The primary outcome variable in this study was patient s perception of symptom improvement graded from zero to four. They used five sessions of biofeedback in a week with each session lasting for 30 min, using EMG instrument. At 6 and 12 months, 80% patients reported major improvement in symptoms with biofeedback as compared to 22% with laxatives. Almost similar results have been shown in the present study (62% reporting overall improvement at 1 month). However, the long-term follow up is not available in the present study. The phenotype of constipation appears to be one of the major determinants of success of biofeedback. In a study, comparing efficacy of biofeedback in patients with DD and STC [8], 71% and 8% patients reported improvement in their bowel habits, respectively. Also, 50% patients, who had features of both types of constipation, reported symptomatic improvement with biofeedback. Moreover, patients in the DD experienced greater improvements in stool frequency, laxative use, straining, and bloating than patients in the STC group. Although there are few studies which show that biofeedback is also effective in STC, they have been criticized for their lack of strict differentiation between DD and STC [10, 12, 25]. Because in real-life situations, most patients show some overlap of both the phenotypes; whatever improvement might have occurred in the STC group may be actually due to underlying dyssynergia. Presence of IBS along with DD does not affect the overall response [19]. However, if the CTT is delayed in presence of IBS and DD, then response to biofeedback is poor [19]. In the present study, CTT was not evaluated. There is wide variation in studies on biofeedback for constipation in the type of intervention, duration of therapy, and outcome measures. Among them, the most important factor, which needs discussion, is the outcome measure to determine success. Most have used one of the three factors as primary outcome: (i) anorectal Fig. 1 High-resolution anorectal manometry plots of patients with fecal evacuation disorder before and after biofeedback treatment with threedimensional reconstruction (indicated by B3-D^) of ano-rectum. The dotted black lines on the plots indicate the time points where 3-D reconstruction was made. Following biofeedback, during attempted defecation, though intra-rectal pressure increased but anal sphincter pressure reduced (reversal of dyssynergic pattern). a, b Before biofeedback. c, d After biofeedback. RP resting pressure, SqP squeeze pressure, AD attempted defecation

In conclusion, the present study demonstrates that biofeedback is effective in patients with DD. It not only improves the overall satisfaction about bowel symptoms but also reverses the dyssynergic pattern of defecation. More prospective studies with long-term follow up are needed on this issue. Acknowledgement The authors thank Mr. Raghunath of the Gastrointestinal Pathophysiology and Motility Laboratory at SGPGI, Lucknow, for his technical support. Compliance with ethical standards AV, AM, and UCG declare that they have no con- Conflict of interest flict of interest. Fig. 2 Defecation index before and after biofeedback treatment among patients with fecal evacuation disorders physiological parameters, (ii) CSBM as assessed by stool diaries, and (iii) global satisfaction in bowel symptoms. Many studies have used multiple outcome measures without stating clearly which was the primary outcome measure. A meta-analysis [26] failed due to the differences between study populations, the heterogeneity of the different samples, and the large range of different outcome measures. In the present study, we compared anorectal parameters to ascertain success of biofeedback because it is more objective and quantifiable. This objective parameter is supplemented by the subjective global satisfaction about the bowel symptoms. The present study is the first one from India reporting effect of biofeedback on anorectal physiological parameters. However, it has got a few limitations. First, there is lack of data on long-term follow up. Second, there is no objective clinical end point in our study. Fig. 3 Pie chart showing number of patients in various categories of dyssynergia Ethics statement The authors declare that the study was performed in a manner to conform with the Helsinki Declaration of 1975, as revised in 2000 and 2008, concerning Human and Animal Rights. References 1. Bharucha AE, Pemberton JH. Locke GR 3rd American Gastroenterological Association technical review on constipation. Gastroenterology. 2013;144:218 38. 2. Shah N, Baijal R, Kumar P, et al. Clinical and investigative assessment of constipation: a study from a referral center in western India. Indian J Gastroenterol. 2014;33:530 6. 3. Ghoshal UC, Verma A, Misra A. Frequency, spectrum, and factors associated with fecal evacuation disorders among patients with chronic constipation referred to a tertiary care center in northern India. Indian J Gastroenterol. 2016;35:83 90. 4. Rao SS, Benninga MA, Bharucha AE, Chiarioni G, Di Lorenzo C, Whitehead WE. ANMS-ESNM position paper and consensus guidelines on biofeedback therapy for anorectal disorders. Neurogastroenterol Motil. 2015;27:594 609. 5. Bharucha AE, Rao SS. An update on anorectal disorders for gastroenterologists. Gastroenterology. 2014;146:37 45.e2. 6. Rao SS. Biofeedback therapy for constipation in adults. Best Pract Res Clin Gastroenterol. 2011;25:159 66. 7. Binnie NR, Papachrysostomou M, Clare N, Smith AN. Solitary rectal ulcer: the place of biofeedback and surgery in the treatment of the syndrome. World J Surg. 1992;16:836 40. 8. Chiarioni G, Salandini L, Whitehead WE. Biofeedback benefits only patients with outlet dysfunction, not patients with isolated slow transit constipation. Gastroenterology. 2005;129:86 97. 9. Chiarioni G, Whitehead WE, Pezza V, Morelli A, Bassotti G. Biofeedback is superior to laxatives for normal transit constipation due to pelvic floor dyssynergia. Gastroenterology. 2006;130:657 64. 10. Chiotakakou-Faliakou E, Kamm MA, Roy AJ, Storrie JB, Turner IC. Biofeedback provides long-term benefit for patients with intractable, slow and normal transit constipation. Gut. 1998;42:517 21. 11. Dailianas A, Skandalis N, Rimikis MN, Koutsomanis D, Kardasi M, Archimandritis A. Pelvic floor study in patients with obstructive defecation: influence of biofeedback. J Clin Gastroenterol. 2000;30:176 80. 12. Emmanuel AV, Kamm MA. Response to a behavioural treatment, biofeedback, in constipated patients is associated with improved gut transit and autonomic innervation. Gut. 2001;49:214 9. 13. Glia A, Gylin M, Gullberg K, Lindberg G. Biofeedback retraining in patients with functional constipation and paradoxical puborectalis contraction: comparison of anal manometry and

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