Anorectal biofeedback for neurogenic bowel dysfunction in incomplete spinal cord injury.

STUDY DESIGN: A case-control study of prospectively collected data was performed. OBJECTIVES: To compare anorectal biofeedback (BF) outcomes in patients with incomplete motor spinal cord injury (SCI) and neurogenic bowel dysfunction (NBD) with a group of functional anorectal disorder-matched control patients. SETTING: Neurogastroenterology Unit affiliated with a Spinal Injury Unit in a tertiary referral centre in Sydney, Australia. METHODS: All consecutive patients with SCI and NBD referred for anorectal manometry and BF were matched in a 1:2 ratio with age, gender, parity and functional anorectal disorder-matched control patients. Instrumented BF was performed in six nurse-guided weekly visits. Outcomes included changes in anorectal physiology measures, symptom scores and quality-of-life measures. RESULTS: Twenty-one patients were included. These were matched with 42 patient controls. Following BF, symptom scores improved significantly in both groups, as did effect of bowel disorder on quality of life. Improvement in these measures did not differ between the groups. Patients with SCI and NBD showed improvement in their sensory and motor anorectal function, including lowering of first sensation threshold and more effective balloon expulsion. CONCLUSIONS: Patients with incomplete motor SCI responded as well to anorectal BF as functional anorectal disorder-matched controls. Spinal cord-injured patients also showed improvement in anorectal sensorimotor dysfunction and balloon expulsion. These novel findings indicate that clinicians should not be dissuaded from considering behaviour-based therapeutic interventions such as anorectal BF in selected spinal cord-injured patients.

Altered temporal characteristics of the rectoanal inhibitory reflex in patients with abdominal distension.

The rectoanal inhibitory reflex (RAIR) is important in gas and stool evacuation. We examined RAIR features in patients with chronic constipation who exhibited bloating with and without abdominal distension, to determine whether alterations in RAIR may be a factor in the pathogenesis of abdominal distension. Seventy-five female patients with chronic constipation with or without abdominal distension were included in the study. The presence or absence of abdominal distension was assessed according to the Rome II questionnaire. All patients underwent both RAIR and rectal sensitivity testing, and specific RAIR parameters were analyzed. Patients were divided into two groups: abdominal bloating with distension (D, n = 55) and abdominal bloating without distension (ND, n = 20). D had a longer time to the onset of anal sphincter inhibition (latency of inhibition) (P = 0.03) compared with ND. In logistic regression analysis, a combination of age, latency of inhibition and the time measured from onset of inhibition to the point of maximum inhibition predicted abdominal distension (P = 0.002). There were no differences between groups for the time from point of maximum inhibition to recovery and for the percentage of internal anal sphincter relaxation. This is the first study to examine the role of RAIR in patients with abdominal distension. Female patients with constipation and abdominal distension exhibited differences in the temporal characteristics of, but not in the degree of, anal sphincter relaxation compared with patients without distension. Since this study was uncontrolled, further studies are necessary to determine the contribution of altered anorectal reflexes to abdominal distension.

Prolonged balloon expulsion is predictive of abdominal distension in bloating.

OBJECTIVES: Abdominal bloating and distension are common in patients with constipation. The precise mechanism of abdominal distension remains uncertain. We hypothesized that constipated patients with bloating plus distension exhibit a greater degree of anorectal dysfunction, potentially affecting gas evacuation, than those without distension. Therefore, our aim was to evaluate anorectal function and other clinical features in patients with constipation who exhibit bloating with and without distension. METHODS: In all, 88 female patients with abdominal bloating and either non-diarrhea irritable bowel syndrome (IBS) or functional constipation were included in the study. The presence or absence of abdominal distension was assessed according to the Rome II questionnaire, and all patients underwent comprehensive clinical assessment and anorectal function studies. RESULTS: Patients were divided into two groups: abdominal bloating with distension (D; n=53) and abdominal bloating without distension (ND; n=35). D featured a prolonged balloon expulsion time (P=0.005), a higher resting anal sphincter pressure (P=0.002), and a higher maximum anal sphincter squeeze pressure (P=0.015) than ND. They also experienced more bloating (P<0.001), more abdominal pain (P=0.004), harder stools (P=0.01), and more incomplete emptying (P=0.005). In logistic regression modeling, prolonged balloon expulsion time was a significant predictor of abdominal distension (P=0.018). CONCLUSIONS: This is the first study to show that prolonged balloon expulsion time predicts abdominal distension in patients with bloating and constipation. Hence, ineffective evacuation of gas and stool associated with prolonged balloon expulsion may be an important mechanism underlying abdominal distension.

Evidence for pelvic floor dyssynergia in patients with irritable bowel syndrome.

PURPOSE: Although functional constipation is known to often manifest concomitant features of pelvic floor dyssynergia, the nature of pelvic floor symptoms and anorectal dysfunction in non-diarrhea predominant irritable bowel syndrome is less clear. This study aims to compare anorectal sensorimotor function and symptoms of patients who have non-diarrhea predominant irritable bowel syndrome with those who have functional constipation. METHODS: We studied 50 consecutive female patients referred with constipation and 2 or more symptoms of pelvic floor dyssynergia, who also satisfied Rome II criteria for either non-diarrhea predominant irritable bowel syndrome (n = 25; mean age, 47 +/- 3 y) or functional constipation (n = 25; 49 +/- 3 y). Assessments included the Rome II Integrative Questionnaire, a validated constipation questionnaire, Hospital Anxiety and Depression scale, visual analog scores for satisfaction with bowel habit and for impact on quality of life, and a comprehensive anorectal physiology study. RESULTS: Both groups displayed physiological evidence of pelvic floor dyssynergia; but patients with non-diarrhea predominant irritable bowel syndrome exhibited a higher prevalence of abnormal balloon expulsion (P < .01) and less paradoxical anal contraction with strain (P = .045) than patients with functional constipation. These patients with irritable bowel syndrome also reported more straining to defecate (P = .04), a higher total constipation score (P = .02), lower stool frequency (P = .02), a trend toward harder stools (P = .06), and less satisfaction with bowel habit (P = .03) than patients with functional constipation. CONCLUSION: Patients with non-diarrhea predominant irritable bowel syndrome with symptoms of pelvic floor dyssynergia exhibit overall pelvic floor dyssynergia physiology similar to that of patients with functional constipation. Certain features, however, such as abnormal balloon expulsion, may be more prominent in the patients with irritable bowel syndrome. Therapeutic modalities, such as biofeedback, that are effective in patients with functional constipation with pelvic floor dyssynergia should therefore be considered in selected patients with irritable bowel syndrome with pelvic floor dyssynergia.

Long-term outcome of anorectal biofeedback for treatment of fecal incontinence.

BACKGROUND: Long-term outcome data for anorectal biofeedback (BF) for fecal incontinence (FI) is scarce. Our aims were to describe the long-term symptom profile, quality of life, and need for surgery in FI patients following BF. METHODS: One hundred and eight consecutive female patients with FI who completed an instrumented BF course were identified for long-term follow-up. In 61 of 89 contactable patients, outcome measures were assessed at short-term (end of BF), mid-term (9 months median), and long-term (7 years median) follow-up after treatment. KEY RESULTS: Long-term response rate (50% or more reduction in FI episodes/wk compared to before BF and not requiring surgical intervention) was seen in 33/61 (54%) patients. Thirteen of these had complete continence. Improvement was seen at short, mid, and long-term follow-up for patients' satisfaction and control of bowel function. In contrast, fecal incontinence severity index and quality of life measures, which improved in short and mid-term, were no different from baseline by long-term follow-up. Patients classified as short-term responders were far more likely to display a long-term response compared to short-term non-responders (68% vs 18%, P < .001). CONCLUSIONS & INFERENCES: Long-term symptom improvement was observed in more than half of FI patients at 7 year post BF follow-up. Quality of life improvements, however, were not maintained. Patients improving during the initial BF program have a high chance of long-term improvement, while patients who do not respond to BF should be considered early for other therapies.

The importance of a high rectal pressure on strain in constipated patients: implications for biofeedback therapy.

BACKGROUND: A subset of patients with chronic constipation display a relatively high manometric rectal pressure on strain. We hypothesized that these patients represent a unique phenotype of functional defecatory disorder (FDD) and would benefit from undergoing anorectal biofeedback (BF). METHODS: Of 138 consecutive patients with chronic constipation and symptoms of FDD, 19 were defined as having a high rectal pressure on strain, using a statistically derived cut-off of 78 mm Hg. This subset was compared with remaining patients in regard to baseline clinical profile and physiology, and outcome of BF. KEY RESULTS: There was a greater representation of males in the high rectal pressure group. Their constipation score, impact of bowel dysfunction on quality of life and satisfaction with bowel habits did not differ from the remaining patients. Eighty-four percent of patients in the high group successfully expelled the rectal balloon and 95% displayed paradoxical anal contraction on strain (P<.05 compared with the remaining patients). Following BF, 89% of patients in the high group reduced their rectal pressure to normal. End of BF treatment outcomes improved significantly, and to a similar degree, in both groups. CONCLUSIONS & INFERENCES: We have identified a subgroup of patients with dyssynergic symptoms but without a formal Rome III diagnosis of FDD, who were characterized by a high straining rectal pressure. Although these patients displayed some physiological differences to the patients with lower straining rectal pressure, they suffer similarly. Importantly, we have shown that these patients can respond favorably to anorectal BF.

Distension technique influences the relationship between colonic and rectal hypersensitivity in irritable bowel syndrome.

In irritable bowel syndrome (IBS), it remains unclear whether rectal hypersensitivity is a 'marker' of colonic hypersensitivity. Our aim was to examine the relation between colonic and rectal sensitivity in IBS patients, comprising phasic and ramp distension techniques. Twenty IBS patients and 12 healthy subjects (N) underwent stepwise ramp and random phasic barostat distensions in the colon and rectum in random order. The sensory threshold pressure (ramp distension) and the visual analogue scale score (VAS, phasic distension), for pain and non-pain, were recorded. Colonic thresholds were lower, and VAS scores were generally higher, for pain and non-pain sensitivities in IBS compared to N. Rectal thresholds were lower, and VAS scores were higher, for pain but not for non-pain, in IBS compared to N. In IBS, for phasic distension, there was good correlation between the colon and rectum for non-pain (e.g. at 16 mmHg, r=0.59, P=0.006) and pain (r=0.60, P=0.006) sensitivities. In contrast, there was no significant correlation between the colon and rectum for ramp distension. In conclusion, colonic and rectal sensitivity in IBS are correlated in response to phasic but not ramp barostat distensions. The rectum serves as a legitimate 'window' for evaluating colonic hypersensitivity in IBS, provided that phasic distensions are employed.

What is the optimum methodology for the clinical measurement of resting anal sphincter pressure?

UNLABELLED: There are conflicting recommendations from consensus groups with regard to the assessment of resting anal sphincter pressure. Our aims were to evaluate and compare the performance of three recognized techniques for the clinical measurement of resting anal sphincter pressure. METHODS: In each of 54 patients presenting for anorectal manometry, and suffering from constipation or fecal incontinence, three different techniques for assessment of resting anal pressure were undertaken, namely stationary, stationary pull-through and slow pull-through techniques. Resting anal sphincter pressures were compared between groups and between techniques. RESULTS: Mean resting anal sphincter pressure was lower with stationary, compared with stationary pull-through and slow pull-through, techniques (P < or = 0.002). Resting pressure was higher for constipation than incontinence regardless of technique used (P < 0.00001). The techniques were highly correlated with each other (P < 0.0001). The stationary pull-through technique conferred a minor advantage in the discrimination between constipation and incontinence. The stationary technique required significantly less time for completion (P < 0.0001). CONCLUSION: Resting anal sphincter pressure varies according to the specific technique employed, yet each technique is valid. The stationary pull-through technique confers a minor advantage in clinical discrimination of patients, but the stationary technique is more time-efficient. Standardized anal sphincter testing should be established to enable inter-laboratory comparisons.

Mebeverine alters small bowel motility in irritable bowel syndrome.

BACKGROUND AND AIM: Despite its widespread use in irritable bowel syndrome (IBS), limited clinical data exist on the effects of mebeverine hydrochloride on gastrointestinal motility. Human motor activity in the small bowel is more reproducible than that in the large bowel; therefore the aim of this study was to determine in the small bowel the effects of oral mebeverine in both IBS patients and in healthy controls. METHODS: Twelve IBS patients (11 females/1 male, 46 +/- 13 years old)-predominant constipation (IBS-C, n = 6) and predominant diarrhoea (IBS-D, n = 6)-and six healthy controls, underwent continuous 48 h ambulant recording of small bowel motor activity. One low energy (400 kcal) and one high energy (800 kcal) standard meal were administered in each consecutive 24-h period. Subjects received, in blinded fashion, placebo tablets in the first 24 h then mebeverine 135 mg q.d.s. in the second 24 h. RESULTS: Mebeverine had no effect on parameters of small bowel motility in controls. In contrast, in both IBS-C (P = 0.01) and IBS-D (P < 0.05) patients, phase 2 motility index was increased during mebeverine administration. Also, after mebeverine the proportion of the migrating motor complex cycle occupied by phase 2 was reduced in IBS-D (P = 0.01), while phase 2 burst frequency was reduced in IBS-C (P < 0.05). For phase 3 motor activity in IBS-C patients, the propagation velocity was decreased (P < 0.01), and the duration increased (P < 0.01). CONCLUSIONS: These findings suggest that mebeverine, in the initial dosing period, has a normalizing effect in the small bowel in IBS, enhancing contractile activity in a similar fashion to 'prokinetic' agents, as well as producing alterations in motor activity consistent with an 'antispasmodic' effect.

Effects of oral cisapride on small bowel motility in irritable bowel syndrome.

BACKGROUND: Cisapride has been reported to improve symptoms in patients with constipation-predominant irritable bowel syndrome. AIM: To compare the effects of a 24-h oral dose regimen of cisapride on interdigestive and post-prandial small bowel motor activity in irritable bowel syndrome patients with predominant constipation, irritable bowel syndrome patients with predominant diarrhoea and healthy subjects. METHODS: In 12 irritable bowel syndrome patients (11 females, aged 44 +/- 12 years)--constipation-predominant (irritable bowel syndrome-C, n = 5) and diarrhoea-predominant (irritable bowel syndrome-D, n = 7)--and six healthy subjects, small bowel motor activity was continuously recorded using an ambulatory technique over a 48-h period. Subjects received, in single-blind fashion, placebo tablets q.d.s. in the first 24 h then cisapride 10 mg q.d.s. in the second 24 h. Additional control groups were 13 healthy subjects (eight females, aged 39 +/- 13 years) and 10 irritable bowel syndrome patients (10 females, aged 49 +/- 14 years) who were studied in identical fashion but who did not receive cisapride. RESULTS: Cisapride increased migrating motor complex phase 2 motility index in both irritable bowel syndrome-D (P < 0.01) and irritable bowel syndrome-C (P < 0.05) patients, as well as in healthy subjects (P < 0.01). An increase in fasting discrete clustered contractions occurred in irritable bowel syndrome-D patients (P < 0.001) and in healthy subjects (P < 0.01), but not in irritable bowel syndrome-C patients; the proportion of discrete clustered contractions that were propagated, however, increased only in irritable bowel syndrome-D patients (P < 0.001). In addition, cisapride resulted in an increase in post-prandial motility index in irritable bowel syndrome patients (P < 0.05). Such motor alterations were not observed during the 48-h recording period in the healthy or irritable bowel syndrome patient control groups who did not receive cisapride. CONCLUSIONS: Oral cisapride influences interdigestive and post-prandial small bowel motor activity in both irritable bowel syndrome patients and healthy subjects; the effects of cisapride may be more marked in patients with predominant diarrhoea than in patients with predominant constipation.

Efficacy of cisapride therapy in functional dyspepsia.

AIM: To assess the efficacy of cisapride therapy in relieving symptoms of functional dyspepsia. METHODS: After a 2-week placebo run-in period, 61 out of 74 patients were eligible to enter a 4-week double-blind treatment phase, consisting of treatment with cisapride (10 mg) or placebo tablets t.d.s. Gastric emptying was assessed scintigraphically at entry to the study. Patients were stratified before treatment into those with or without active chronic (Helicobacter pylori) gastritis. Patients were also classified retrospectively into those with 'reflux-like' dyspepsia (n = 29) and those with 'motility-like' dyspepsia (n = 32). RESULTS: At the end of the active treatment phase, there was a similar significant (P < 0.001) reduction in total symptom score from baseline in both cisapride (8.9 +/- 0.5 to 5.8 +/- 0.6) and placebo (9.7 +/- 0.6 to 5.5 +/- 0.6) groups. Scores for heartburn and continual bloating were significantly reduced in the cisapride but not the placebo group; improvement was attributable to patients with normal, rather than delayed, rates of gastric emptying. For continual bloating, significant improvement also occurred in the cisapride subgroup without gastritis, but not in the subgroup with gastritis (mean symptom score reduction 0.48 +/- 0.18, P = 0.03). For global evaluation by the investigator and by the patient, the overall improvement rates were not statistically different between cisapride and placebo groups. In those with normal gastric emptying, however, there was a significant (P = 0.01) improvement in general well-being in the cisapride but not in the placebo group. CONCLUSIONS: We were unable to show major differences in the short-term efficacy of cisapride and placebo in functional dyspepsia. There were indications, however, of beneficial effects of cisapride over placebo in those with 'reflux-like' dyspepsia, and in those without gastroparesis.

Life stress and non-ulcer dyspepsia: a case-control study.

Sixty-two patients with persistent NUD symptoms were compared with healthy persons of comparable age, sex and social status on a variety of life stress, personality, mood state and coping measures. Highly threatening chronic difficulties were significantly more evident in the NUD group than controls (98 and 2% respectively), as were acute life events which remained highly threatening one week after their onset. Other psychological variables significantly related to NUD were high levels of anxiety and depressive symptoms, personality traits indicating neurotic or anxious tendencies, a tendency to use less mature stress-coping mechanisms and to have less high-quality emotional support. Multivariate analysis revealed the presence of highly threatening stressors to be by far the most important predictor of NUD status. The implications of these findings in relation to the significance of stress and other psychological variables in the aetiology and treatment of NUD are discussed.

Psychological symptom profiles in patients with chest pain.

Five-hundred and thirty-two patients with ischaemic-like chest pain referred for symptom-limited exercise thallium myocardial perfusion studies, were assessed on a range of psychosocial measures. Three groups of patients were identified on the basis of their perfusion studies: (1) normal thallium perfusion; (2) current myocardial ischaemia; and (3) past myocardial infarction (but no current ischaemia). There were no significant psychological differences between these groups on a wide range of measures which included depression, state and trait anxiety, Type A behaviour, personality, suppression of affect, locus of control, alexythymia, and hypochondriasis. Significant differences were identified, however, on measures of anger and coping style. Subjects with no current ischaemia (normal thallium perfusion and those with past myocardial infarction) had higher scores on 'immature coping' and 'anger in', than subjects with current myocardial ischaemia. These findings are discussed in the light of other published research.

Misuse of multivariate analysis of variance in behavioral research: the fallacy of the "protected" F test.

Researchers who examine multiple outcome variables sometimes invoke a multivariate analysis of variance approach known as the "protected F test" to control for experimentwise Type I error rate. Unfortunately, this procedure affords protection against experimentwise Type I error only in rare instances. The purpose of the present paper is to present the case against the protected F test and to discuss alternative methods of controlling for Type I error, including the Bonferroni adjustment and descriptive discriminant analysis. The latter approach is briefly elaborated as a truly multivariate solution for multivariate phenomena. The author cites multiple examples of proper and improper use of multivariate analysis of variance in research on child development.

Predictors of outcome of anorectal biofeedback therapy in patients with constipation.

BACKGROUND: Anorectal biofeedback therapy (BFT) is a safe and effective treatment in patients with constipation. Given the high prevalence of constipation and therefore high demand for BFT, there is a need to prioritise patients. AIMS: To explore clinical features and anorectal physiology which predict success or failure of BFT and to derive a statistical model which helps to predict the success of BFT. METHODS: A total of 102 patients with constipation referred for BFT were evaluated. All patients underwent comprehensive clinical and anorectal function assessment, including balloon expulsion testing. The BFT protocol consisted of a comprehensive 6-weekly visit programme comprising instruction on toilet behaviour and abdominal breathing, achieving adequate rectal pressure and anal relaxation, and balloon expulsion and rectal sensory retraining. Success of BFT was based on an improvement in global bowel satisfaction. RESULTS: Harder stool consistency (P=0.009), greater willingness to participate (P<0.001), higher resting anal sphincter pressure (P=0.04) and prolonged balloon expulsion time (P=0.02) correlated with an improvement in bowel satisfaction score. A longer duration of laxative use (P=0.049) correlated with no improvement in bowel satisfaction score. Harder stools, shorter duration of laxative use, higher straining rectal pressure and prolonged balloon expulsion independently predicted successful BFT. A model (S(i) = (p)∑ ß(j)X(ij), where ß represents a regression coefficient, X is a given predictive variable and S(i) is the weighted index score for each individual) incorporating these four variables enabled prediction of successful BFT, with sensitivity and specificity of 0.79 and 0.81, respectively. CONCLUSIONS: Important clinical and anorectal physiological features were found to be associated with outcome of anorectal biofeedback therapy in patients with constipation. This information and the predictive model will assist clinicians to prioritise patients for anorectal biofeedback therapy.

Relationships between pelvic floor symptoms and function in irritable bowel syndrome.

BACKGROUND: Pelvic floor dyssynergia (PFD) within irritable bowel syndrome (IBS) is often overlooked and the relationship between symptoms and physiology is relatively unexplored. Our aims were to determine relationships between clinical features and anorectal function in non-diarrhea predominant IBS (non-D IBS) patients and whether certain clinical or physiological features predict PFD in IBS. METHODS: Two groups of patients were evaluated. Group I: 32 female non-D IBS patients with >or=2 symptoms suggesting PFD underwent comprehensive symptom and anorectal function assessment. Group II: 32 female non-D IBS patients recruited from the community underwent symptom assessment. KEY RESULTS: Prevalence of PFD symptoms was similar in both groups. In group I patients, increased frequency of digitation was associated with a longer balloon expulsion time (P = 0.03). Higher scores for anal pain were associated with both a low resting anal pressure (P = 0.04) and a shorter duration of maximum squeeze (P = 0.03). Reduced perineal descent was associated with anxiety (P = 0.03) and depression (P = 0.01). A shorter duration of maximum squeeze was associated with higher parity (P = 0.02) and previous hysterectomy (P = 0.047). Duration of PFD symptoms was higher (P = 0.02) and maximum tolerated volume was lower (P = 0.05) in 22 patients with a physiological diagnosis of PFD compared to 10 without PFD. No symptoms independently predicted a physiological diagnosis of PFD. CONCLUSIONS & INFERENCES: Important relationships between certain PFD symptoms and disordered anorectal physiology have been demonstrated in these non-D IBS patients. However, symptoms alone could not predict PFD, and certain clinical features should therefore highlight the need for comprehensive anorectal function tests.

Colorectal responses to distension and feeding in patients with spinal cord injury.

The role of the central nervous system in enteroenteric motor reflexes remains controversial. Our aims were as follows: 1) to evaluate colorectal, rectocolic, gastrocolonic, and gastrorectal reflex responses in patients with cervical spinal cord injury (SCI) and 2) to compare these responses with those in healthy subjects. In six patients with SCI (5 male, 42 +/- 4 yr) and six healthy control subjects (5 male, 36 +/- 5 yr), 2-min phasic distensions were performed randomly via dual-barostat balloons in the colon and rectum. Continuous colonic and rectal balloon volumes were recorded during distensions and after a 1,000-kcal liquid meal. Mean balloon volumes were recorded before, during, and after phasic distensions and over 60 min postprandially. The colorectal response was similar in control subjects and SCI patients (rectal volume reduction = 28 +/- 11% and 15 +/- 5% in SCI patients and healthy subjects, respectively); the rectocolic response was variable. The gastrocolonic response was present in all subjects (colonic volume reduction = 49 +/- 4% and 44 +/- 3% in SCI patients and healthy subjects, respectively), with a time effect in the first 30 min (P < 0.0001) and a group effect in the second 30 min (P < 0.004). The gastrorectal response was present in four SCI patients and five healthy subjects (rectal volume reduction = 38 +/- 4% and 41 +/- 3% in SCI patients and healthy subjects, respectively), with a time effect in the first 30 min (P < 0.0001) but no group effect in the second 30 min. Intact neural transmission between the spinal cord and higher centers is not essential for normal colorectal motor responses to feeding and distension; however, a degree of central nervous system and neurohormonal modulation of these responses is likely.