Age and anorectal sensibility in normal women

Long-term anorectal function in rectal cancer patients treated with chemoradiotherapy and endorectal brachytherapy

AIM

The aim was to study anorectal function in long-term survivors after combined, curatively intended, chemoradiotherapy and endorectal brachytherapy for low rectal cancer.

METHODS

This was a case-control design. We compared anorectal function by anal manometry, anal functional lumen imaging probe (EndoFLIP) and rectal bag distension in rectal cancer patients (RCPs) and healthy, normal subjects (NSs). Symptoms were assessed by the low anterior resection syndrome (LARS) and Wexner faecal incontinence scores.

RESULTS

Thirteen RCPs (12 men, median age 68 years, range 52-92) after 60 Gy radiotherapy, 5 Gy endorectal brachytherapy and oral tegafur-uracil with complete clinical response (median time since treatment 2.8 years, range 2.2-5.6) were compared to 15 NSs (14 men, median age 64 years, range 47-75). RCPs had lower than normal anal resting pressure, 38.6 mmHg (range 8.8-67.7) versus 58.8 mmHg (25.7-105.2) (P < 0.003), and squeeze pressure, 117 mmHg (55.2-203) versus 188 mmHg (103-248) (P < 0.01). Squeeze-induced pressure increase recorded by EndoFLIP was also lower in RCPs (q > 7.56, P < 0.001) as was the anal canal resistance to increasing distension (q = 3.13, P < 0.05). No differences in median rectal volume at first sensation (72 [22-158] vs. 82 [36-190] ml, P = 0.4) or at urge to defaecate (107 [42-227] vs. 132 [59-334] ml, P = 0.2) were found. However, maximum tolerable rectal volume was lower in RCPs (145 [59-319] vs. 222 [106-447] ml, P < 0.02). The median (range) low anterior resection syndrome score was 27 (0-39) for RCPs and 7 (0-23) for NSs (P < 0.001), while the Wexner score was 0 (0-5) versus 0 (0-4) (P = 0.56).

CONCLUSION

Radiotherapy combined with endorectal brachytherapy for rectal cancer causes long-term anorectal symptoms, impaired anal sphincter function and reduced rectal capacity.

Fecal Incontinence in the Elderly

Fecal incontinence can be a challenging and stigmatizing disease with a high prevalence in the elderly population. Despite effective treatment options, most patients do not receive care. Clues in the history and physical examination can assist the provider in establishing the diagnosis. Direct inquiry about the presence of incontinence is key. Bowel disturbances are common triggers for symptoms and represent some of the easiest treatment targets. We review the epidemiology and impact of the disease, delineate a diagnostic and treatment approach for primary care physicians to identify patients with suspected fecal incontinence and describe appropriate treatment options.

Cortical processing to anorectal stimuli after rectal resection with and without radiotherapy

BACKGROUND

Bowel dysfunction is common after surgery for rectal cancer, especially when neoadjuvant radiotherapy is used. The role of sensory function in the pathogenesis remains obscure, and the aim of the present study was to characterize the sensory pathways of the brain-gut axis in rectal cancer patients treated with resection ± radiotherapy compared with healthy volunteers.

METHODS

Sensory evaluation by (neo)rectal distensions was performed and sensory evoked potentials (SEPs) were recorded during rapid balloon distensions of the (neo)rectum and anal canal in resected patients with (n = 8) or without (n = 12) radiotherapy. Twenty healthy volunteers were included for comparison. (Neo)rectal latencies and amplitudes of SEPs were compared and spectral band analysis from (neo)rectal and anal distensions was used as a proxy of neuronal processing.

RESULTS

Neorectal sensation thresholds were significantly increased in both patient categories (all p < 0.008). There were no differences in (neo)rectal SEP latencies and amplitudes between groups. However, spectral analysis of (neo)rectal SEPs showed significant differences between all groups in all bands (all p < 0.01). On the other hand, anal SEP analyses only showed significant differences between the delta (0-4 Hz), theta (4-8 Hz) and, gamma 32-50 Hz) bands (all p < 0.02) between the subgroup of patients that also received radiotherapy and healthy volunteers.

CONCLUSIONS

Surgery for rectal cancer leads to abnormal cortical processing of neorectal sensation. Additional radiotherapy leads to a different pattern of central sensory processing of neorectal and anal sensations. This may play a role in the functional outcome of these patients.

Effect of gender on the etiology of fecal incontinence: Retrospective analysis of a tertiary referral center in Turkey

BACKGROUND/AIMS

Anorectal diseases, including fecal incontinence, are prevalent and have an enormous impact on the quality of life. Therefore, investigating their etiological factors may help to reduce the incidence and/or the severity of the underlying diseases.

MATERIALS AND METHODS

Referral complaints (constipation, strained defecation, and incontinence) and medical and anorectal manometry records of 883 (562 female/321 male, ages 45.17±1.00 and 48.41±0.63 years, respectively) patients were evaluated retrospectively. Maximal resting pressure (MRP) and maximal squeeze pressure (MSP) measured by stationary pull-through technique, volume of rectoanal inhibitory reflex, and sensory threshold to rectal balloon distention (ST) were obtained by water perfusion system. Data were compared according to referral complaints, age, gender, parity, and underlying diseases.

RESULTS

Incontinence was the most frequent referral complaint in 61.2% of females and 67.6% of males. MRP and MSP were significantly lower in incontinent females than in the other groups. In incontinent males, MSP was lower than the strained defecation group, and ST was higher than the constipation group. Age was negatively correlated with MRP for both of the genders and in all groups. Obstetric trauma (85%) and number of parity (3.40±2.59) were significantly higher in incontinent females. Moreover, the most prevalent underlying disease was diabetes in incontinent females (13.7%) and neurological diseases, including traumas, in incontinent males (41.5%).

CONCLUSION

Increasing awareness of labor safety, controlling diabetes mellitus, and preventing obstetric traumas may reduce the prevalence of fecal incontinence.

Increased yield pressure in the anal canal during sacral nerve stimulation: a pilot study with the functional lumen imaging probe

BACKGROUND

Sacral nerve stimulation (SNS) is a well-established treatment for fecal incontinence but its mode of action remains obscure. Anal sphincter function is usually evaluated with manometry but resistance to distension may be a more appropriate parameter than luminal pressure. The functional lumen imaging probe allows detailed description of distension properties of the anal canal. Our objective in this study was to characterize the impact of SNS on distension properties of the anal canal in patients with idiopathic fecal incontinence.

METHODS

We studied 10 women (median age 64 [44-79] years) with idiopathic fecal incontinence at baseline and during SNS. The luminal geometry of the anal canal was examined with the FLIP at rest and during squeeze and the distensibility of the anal canal was investigated during filling of the bag.

KEY RESULTS

All patients were successfully treated with SNS and the mean Wexner Incontinence Score was reduced from 14.9 ± 4 to 7.1 ± 4.8 (P<.001). The pressure required to open the narrowest point of the anal canal during distension (yield pressure) increased from 14.5 ± 12.2 mmHg at baseline to 20.5 ± 13.3 mmHg during SNS (P<.01). The pressure-strain elastic modulus increased non-significantly from 2.2 ± 0.5 to 2.9 ± 1.6 kPa, indicating increased stiffness of the anal canal.

CONCLUSION AND INFERENCES

The yield pressure and the resistance to distension increased in response to SNS for idiopathic fecal incontinence. This will inevitably increase the resistance to flow through the anal canal, which may contribute to the benefits of sacral nerve stimulation.

Does Sacral Nerve Stimulation Improve Continence Through Enhanced Sensitivity of the Anal Canal? A Pilot Study

BACKGROUND

It has been suggested that the effects of sacral nerve stimulation against fecal incontinence involve neuromodulation at spinal or supraspinal levels.

OBJECTIVE

This study aims to investigate the afferent sensory pathways from the anorectum before and during sacral nerve stimulation.

DESIGN

This is an explorative study.

PATIENTS

Fifteen women with idiopathic fecal incontinence (mean age, 58 ± 12.2 years) were selected.

INTERVENTIONS

Cortical evoked potentials were recorded during repeated rapid balloon distension of the rectum and the anal canal both before and during temporary sacral nerve stimulation. Stimuli applied were individualized according to the subjective urge to defecate.

MAIN OUTCOME MEASURES

The main outcomes measured were 1) stimulus intensity, 2) latencies and amplitudes of cortical evoked potentials, and 3) spectral content in predefined frequency bands of cortical evoked potentials.

RESULTS

The median Wexner fecal incontinence score improved from 15.5 ± 3.6 before to 6.7 ± 5 during sacral nerve stimulation (p < 0.001). Sacral nerve stimulation did not affect the threshold for urge to defecate during rectal distension (p = 0.64) but reduced the threshold from stimulation of the anal canal by 50% (p = 0.03). No statistically significant differences were found in latencies, amplitudes, or spectral analysis.

LIMITATIONS

This is a pilot study of limited size.

CONCLUSIONS

In patients with idiopathic fecal incontinence, sacral nerve stimulation reduced the threshold for urge to defecate elicited from the anal canal, whereas supraspinal responses remained unaltered. This may suggest that sacral nerve stimulation, at least in part, acts via somatic afferent fibers enhancing anal sensation.

Sacral nerve stimulation changes rectal sensitivity and biomechanical properties in patients with irritable bowel syndrome

BACKGROUND

Sacral nerve stimulation (SNS) has been demonstrated to alleviate symptoms and improve quality of life in selected patients with irritable bowel syndrome (IBS). The mechanisms of action, however, remain unknown. The aim of the study was to evaluate the effects of SNS on rectal sensitivity and biomechanical properties in patients with IBS.

METHODS

Twenty patients with diarrhea-predominant (n = 11) or mixed (n = 9) IBS were treated with SNS in a controlled, randomized crossover trial. They were randomized to either 1 month of SNS (ON) or placebo (OFF) with the opposite setting for the next month. Sensory and biomechanical parameters were assessed by multimodal rectal stimulation at the end of each period. IBS-specific symptoms were evaluated at baseline and at the end of each treatment period.

KEY RESULTS

Cold stimuli were better tolerated in the ON period (19.9 °C[± 0.6]) compared to the OFF period (21.8 °C[± 0.6]; p = 0.03). Significantly lower cross-sectional areas were needed to elicit sensory responses in the ON period (1545 mm(2) [± 95]) compared to the OFF period (1869 mm(2) [± 92]; p = 0.015). The association between reduced sensory threshold and improvement of constipation was of borderline significance (p = 0.05). Wall stiffness was significantly lower in the ON period (192 mmHg[± 10]) compared to the OFF period (234 mmHg[± 10]; p = 0.004). Reduced wall stiffness was significantly associated with improved overall GSRS-IBS symptom score (p = 0.01). Reduced sensory threshold to stretch (p = 0.02) and reduced wall stiffness (p < 0.001) were predictors of the GSRS-IBS symptom score.

CONCLUSIONS & INFERENCES

SNS for diarrhea-predominant and mixed IBS relaxes the rectal wall, while making it more sensitive to stretch and less sensitive to cold. Reduced wall stiffness and increased sensitivity to stretch are associated with improved GSRS-IBS symptom score.

A randomised, controlled study of small intestinal motility in patients treated with sacral nerve stimulation for irritable bowel syndrome

Background

Irritable bowel syndrome (IBS) is among the most common gastrointestinal disorders worldwide. In selected patients with severe diarrhoea-predominant or mixed IBS subtypes sacral nerve stimulation (SNS) alleviates IBS-specific symptoms and improves quality of life. The mode of action, however, remains unknown. The present study aimed to evaluate the effect of SNS on small intestinal motility in IBS patients.

Methods

Twenty patients treated with SNS for severe diarrhoea-predominant or mixed IBS were included in a randomised, controlled, crossover study. The neurostimulator was turned ON or OFF for the first one month and then to the opposite setting for the next month. Gastrointestinal transit patterns were investigated with the Motility Tracking System-1 (MTS-1) at the end of each the ON and OFF period. Primary endpoint was change in the velocity of the magnetic pill within the small intestine. Statistical testing was performed with Wilcoxon’s rank sum test and Fisher’s exact test.

Results

The median velocity of the magnetic pill through the small intestine in the fasting state was not significantly different between periods with and without SNS (Group ON-OFF: median change 0 m/h (range -1.07, 0.63), Group OFF-ON: median change 0.27 m/h (range -0.59, 1.12)) (p = 0.25). Neither, was the median velocity of the magnetic pill through the small intestine in the postprandial state significantly different between periods with and without SNS (Group ON-OFF: median change -0.13 m/h (range -0.46, 0.23), Group OFF-ON: median change 0.015 m/h (range -0.48, 0.59)) (p = 0.14).

Conclusion

Even though SNS may reduce symptoms of diarrhoea-predominant and mixed IBS, it has no detectable effect on small intestinal transit patterns.

Trial registration

Clinical.trials.gov, (NCT00919672).

Fecal incontinence in the elderly: FAQ

Fecal incontinence (FI) is a common gastrointestinal (GI) complaint in patients aged 65 years and older. This evidence-based review article discusses the epidemiology, pathophysiology, evaluation, and management of FI in the geriatric population. We emphasize aging-related changes leading to and impacting evaluation and treatment of this symptom while incorporating the core geriatric principles of functional status and management aligned with patient preference and goals of care.

Sigmoid compliance and visceral perception in spinal cord injury patients

Intestinal motor and sensory dysfunctions in traumatic complete or incomplete spinal cord injury (SCI) are frequent and result in altered mechanisms of defecation. The aim of this study is to investigate sigmoid compliance and perception in chronic SCI patients. Sigmoid responses to fixed-tension distentions were assessed using a tensostat in six patients (six men, 42 ± 4 years) with chronic complete transection of the spinal cord (high-SCI; five tetraplegic C5-C7 and one paraplegic T4-T6) and impaired evacuation (i.e. constipation). A group of 10 healthy individuals (six men, 25 ± 1 years) served as controls. SCI patients had higher sigmoid compliance at the highest distention level than the controls (10.3 ± 2.4 vs. 5.1 ± 0.8 ml/mmHg; P<0.05). Perception scores at first sensation were higher in SCI patients (2.3 ± 0.7 vs. 1.1 ± 0.1; P<0.05), but were not different at the highest distention levels (3.7 ± 0.8 vs. 3 ± 1; NS). The most commonly reported sensation by patients was distention/bloating and was referred less commonly to the hypogastrium compared with distention/bloating in controls. An increased sigmoid compliance can be detected in constipated SCI patients. The preservation of some degree of visceral sensations, although abnormally referred, could imply the occurrence of sensory input remodeling at the spinal level.

Anorectal function after long-term transanal colonic irrigation

AIM

The increased use of transanal colonic irrigation (TAI) warrants study of its effects on anorectal function after long term use.

METHOD

Anorectal physiology tests were performed in 12 patients with chronic idiopathic constipation (CC) and 10 with idiopathic faecal incontinence (FI) [median 55 years (range 21-70)] before and after a median 68 (range 32-113) months use of TAI.

RESULTS

In CC median, urge rectal volume increased from 121 (70-264) to 268 ml (69-484) (P = 0.05) whereas rectal compliance, volume at first sensation, maximum tolerable rectal volume, anal sensory level, median anal resting and squeeze pressures were unaltered. In FI median, urge volume increased from 125 (range 50-221) to 158 ml (range 97-287) (P = 0.033) and maximum tolerable volume increased from 156 (80-321) to 253 ml (162-332) (P = 0.047). Median anal resting pressure decreased from 48 (29-100) to 32 cmH(2) O (12-79) (P = 0.011) and anal squeeze pressure decreased from 69 (30-107) to 38 cmH(2) O (30-70) (P = 0.017). Rectal compliance, volume at first sensation and anal sensory level were unaltered.

CONCLUSIONS

As rectal compliance was unaltered, it is likely that the increased rectal tolerable volume is explained by patients adapting to irrigation rather than by changes in the property of the mechanical rectal wall. As anal sphincter function was deteriorated only in FI, we suggest that this is because of the natural history of FI rather than any effect of long term TAI.

Faecal incontinence in older people

Faecal incontinence in older people is a distressing and socially isolating symptom and increases the risk of morbidity, mortality and dependency. Many older individuals with faecal incontinence will not volunteer the problem to their general practitioner or nurse and, regrettably, health care providers do not routinely enquire about the symptom. Even when older people are noted by health care professionals to have faecal incontinence, the condition is often managed passively, especially in the long-term care setting where it is most prevalent. The importance of identifying treatable causes of faecal incontinence in older people, rather than just managing passively, is strongly emphasized in national and international guidance, but audit shows that adherence to such guidance is generally poor. This article describes epidemiology, causes, assessment, diagnosis and treatment of faecal incontinence in older people.

Rectal hyposensitivity: evaluation of anal sensation in female patients with refractory constipation with and without faecal incontinence

Rectal hyposensitivity (RH) is commonly found in patients with intractable constipation, faecal incontinence or both. Anal sensation may also be blunted in these conditions. We aimed to determine whether RH is associated with anal hyposensitivity, which may reflect a combined viscero-somatic neuropathy. One hundred and fifty-eight female patients with chronic constipation underwent physiological investigation including rectal sensation to volumetric balloon distension, and distal anal mucosal sensation to electrostimulation. Data were also obtained from 32 healthy female volunteers. Anal mucosal electrosensory thresholds were significantly higher in patients compared with volunteers (median: 2.4 mA, range: 0.4-19.6 vs 1.1 mA, range: 0.1-4.2, respectively), although the patient group was older (P < 0.0001), but there was no difference (P = 0.572) in the incidence of blunted anal sensation between those with normal rectal sensation (n = 113, 20% abnormal) and RH (n = 45, 24% abnormal). Irrespective of rectal sensory function, there was a strong association between symptom duration (P = 0.012) and anal hyposensitivity. One-fifth of constipated female patients had evidence of diminished anal sensation. However, the presence of RH was not associated with an increased frequency of anal hyposensitivity, thereby suggesting that different aetiopathogenic mechanisms underlie the development of anal and rectal hyposensitivity. Further studies in carefully selected, homogenous patient populations are necessary to elucidate these mechanisms.

Age effects on anorectal pressure in anal continent women with lower urinary tract dysfunction

The objective of this paper is to evaluate age and associated factors affecting anorectal pressure profilometry in anal-continent women with lower urinary tract symptoms. One hundred and ten anal-continent women (mean age, 47.7+/-12.8 years; range, 23-87 years) with lower urinary tract symptoms voluntarily participated in this study after undergoing a complete urogynecological evaluation including a multichannel urodynamic study. Anorectal pressure was evaluated by using a radial four-channel manometry with a water-filled catheter, which was placed 10 cm into the anorectum above the anal verge. We divided the anorectal pressure profile into five segments and four axes to clarify the axis-specific defect or site-specific damage in the sphincter profile. The aging process had a negative effect on the peak resting pressure from the 41 to 100th percentile of the anorectal pressure profile at 12 o'clock, 3 o'clock, and 6 o'clock (P<0.05). With voluntary squeezing, aging had negative effects on the peak squeeze pressure from the 41 to 100th percentile of the anorectal pressure profile at 3 o'clock, and 61 to 80 percentile at 12 o'clock (P<0.05). There is a trend where anorectal pressure reduces as a woman ages, especially at the anal sphincter area in women with lower urinary tract symptoms. The anterior and left sides of the anorectal sphincter seem to be the most vulnerable in the aging process.

Update of tests of colon and rectal structure and function

This review deals with the indications, methods, strengths, and limitations of anorectal testing in clinical practice. In chronic constipation, anal manometry and a rectal balloon expulsion test, occasionally supplemented by defecography, are useful to identify a functional defecatory disorder, because symptoms may respond to pelvic floor retraining. In patients with fecal incontinence, diagnostic testing complements the clinical assessment for evaluating the pathophysiology and guiding management. Manometry measures anal resting and squeeze pressures, which predominantly reflect internal and external anal sphincter function, respectively. Defecation may be indirectly assessed by measuring the recto-anal pressure gradient during straining and by the rectal balloon expulsion test. Endoanal ultrasound and magnetic resonance imaging (MRI) can identify anal sphincter structural pathology, which may be clinically occult, and/or amenable to surgical repair. Only MRI can identify external sphincter atrophy, whereas ultrasound is more sensitive for internal sphincter imaging. By characterizing rectal evacuation and puborectalis contraction, barium defecography may demonstrate an evacuation disorder, excessive perineal descent or a rectocele. Dynamic MRI can provide similar information and also image the bladder and genital organs without radiation exposure. Because the measurement of pudendal nerve latencies suffers from several limitations, anal sphincter electromyography is recommended when neurogenic sphincter weakness is suspected.

Relation between anal electrosensitivity and rectal filling sensation and the influence of age

PURPOSE

The aim of this study was to assess the effect of age and sex on the rectal filling sensation and anal electrosensitivity and to explore the relation between anal electrosensitivity and the parameters of the rectal filling sensation.

METHODS

Anal mucosal electrosensitivity and anorectal manometry, including the rectal filling sensation test were performed in 19 control subjects; 10 were younger than 60 years and 9 were older than that. Altogether, there were 11 men and 8 women.

RESULTS

Anal electrosensitivity did not differ between the two age groups. Women had a significantly lower electrosensitivity 4 and 5 cm from the anal verge than men, as well as a significantly shorter anal high-pressure zone. The rectal filling sensation did not differ between sexes. In the older age group, the rectal volumes required to induce filling sensations were smaller than those observed in the younger age group, but rectal pressures were comparable; as a consequence, rectal compliance was lower in older subjects. Anal electrosensitivity at different anal levels did not correlate with the rectal volume or pressure parameters of successive rectal filling sensations. The pressure recorded in the proximal anal canal at the consecutive rectal filling sensations strongly correlated with the rectal balloon pressure needed to elicit them.

CONCLUSIONS

The zones of high anal electrosensitivity and high pressure seem to coincide. The fact that both are shorter in females did not influence the parameters of the rectal filling sensation. Lower rectal volumes but comparable rectal pressures were needed to induce the rectal filling sensation in the older age group. Rectal sensation did not correlate with anal electrosensitivity, probably because the receptors are not stimulated by the type of anal stimulation used or because different receptors are involved. Hence, the rectal filling sensation test cannot be replaced by the simpler anal electrosensitivity test.

Day-to-day reproducibility of anorectal sensorimotor assessments in healthy subjects

The reproducibility of tests widely utilized to assess anorectal sensorimotor functions is not well established. Our aims were to assess the intra-individual day-to-day reproducibility of these parameters in healthy subjects. Anal sphincter pressures were assessed by perfusion manometry on two separate days in 19 healthy subjects. Rectal pressure-volume (p-v) curves and sensory thresholds were assessed in 12/19 subjects by inflating a highly compliant polyethylene balloon from 0 to 32 mmHg in 4 mmHg steps. Subjects also rated intensity of perception by visual analogue scale (VAS) during phasic distentions 8, 16 and 24 mmHg above operating pressure, in randomized sequence. Resting and squeeze anal pressures and rectal compliance were highly reproducible (r(s) > or = 0.7) in the same subject on separate days. Pressure thresholds for urgency appeared less reproducible than thresholds for initial perception and the desire to defecate. VAS scores were highly reproducible only during the 24-mmHg distention. Thus, anal pressures and rectal compliance are highly reproducible within healthy subjects on separate days, while sensory thresholds are reproducible to a variable degree, dependent on the intensity of stimulation and the perception being assessed.

Constipation and fecal incontinence in the elderly

Although constipation and fecal incontinence are common symptoms in the elderly, relatively little research has been done to differentiate physiologic changes in rectoanal function resulting from aging and pathologic changes resulting from diseases occurring as patients age. Certain physiologic changes occur in many older patients and may predispose them to the development of constipation or fecal incontinence. These symptoms need the same thoughtful evaluation and management in the elderly as in younger patients. Results of therapy often can be good, leading to alleviation of suffering and the ability to lead a fuller life.

Flatus and faecal incontinence: prevalence and risk factors at 16 weeks of gestation

OBJECTIVE

To evaluate the prevalence of anal incontinence at 16 weeks of gestation and to identify possible maternal and obstetrical risk factors.

DESIGN

Cross sectional study and cohort study.

SETTING

Department of Obstetrics and Gynaecology, Aarhus University Hospital, Denmark.

PARTICIPANTS

Cross sectional study: 7,557 women attending antenatal care. Cohort study: a subgroup of 1,726 pregnant women with one previous delivery at our department.

RESULTS

The prevalence of anal incontinence within the preceding year was 8.6%. Incontinence of liquid and solid stools was reported in 2.3% and 0.6%, respectively. Isolated flatus incontinence at least once a week was reported in 4.2%. The risk of flatus incontinence at least once a week was increased with age > 35 years (OR 1.6; 95% CI 1.1-2.4) and with previous lower abdominal or urological surgery (OR 1.5, 95% CI 1-1-2.1) in a logistic regression model controlling for maternal factors. Increasing parity did not increase the risk. The risk of flatus incontinence was increased after anal sphincter tear and birthweight > 4,000 g in a logistic regression model controlling for maternal and obstetric variables. Episiotomy was insignificantly associated, while spontaneous perineal tear > 3 cm and a number of other intrapartum factors were not associated. CONCLUSION True faecal incontinence is rare among younger women. However, an age > 35 years and previous lower abdominal or urological surgery increased the risk of flatus incontinence in contrast to increasing parity. This suggests that childbirth plays a minor role compared with age. However, when analysing obstetric variables separately, a birthweight > 4,000 g, and anal sphincter tears were significant risk factors for flatus incontinence.

The role of the barostat in human research and clinical practice

BACKGROUND

The barostat is a recently developed device used to study the physiology and pathophysiology of the motor and sensory functions of the gastrointestinal tract. It can monitor volume changes while maintaining a set constant pressure and deliver controlled distensions of gastrointestinal organs. Simultaneously, motility and visceral perception may be assessed. The barostat has contributed to the understanding of physiological processes in the gastrointestinal tract with regard to regulation of tone, compliance, enteric reflexes, sensation and processing of signals to and from the gut. In addition, the barostat has been used to study various gastrointestinal disorders. In functional bowel disorders, objective abnormalities in visceral sensitivity and enteric reflexes have been demonstrated. Numerous other diseases, gastrointestinal in origin as well as systemic diseases affecting the gut, have been studied. In the near future, the barostat may become a clinically useful tool for the objective diagnosis of motor and sensitivity disorders of the gut and for monitoring the effectiveness of therapy.

Influence of age on rectal tone and sensitivity to distension in healthy subjects

Hypersensitivity to rectal distension is frequently observed in patients with irritable bowel syndrome (IBS). However, few data are available about the influence of age on rectal sensory thresholds and tone. The aim of this study was to measure rectal sensory thresholds and tone with a barostat in 12 healthy subjects (aged 86 +/- 4 years, eight females, four males) as compared with 12 young healthy male controls (26 +/- 1 years). Isobaric phasic distensions were performed in the fasted state (increment of 4 mmHg, steps of 5 min, interval of 5 min). Rectal tone changes were then measured as changes in volume of the barostat bag, the pressure being kept constant. After a baseline recording of 1 h, a 1000-kcal meal was served and the tone recorded until return to baseline. Rectal sensory thresholds were significantly higher in aged subjects. First sensation, sensation of urge to defaecate and sensation of pain were triggered at 21.1 +/- 3.2 mmHg, 30.4 +/- 5.4 mmHg and 40.5 +/- 5.0 mmHg, respectively, in aged subjects, vs 13.3 +/- 4.6 mmHg (P < 0.05), 20.7 +/- 1.0 mmHg (P < 0.001) 31.3 +/- 1.7 mmHg (P < 0.001) in controls. Rectal compliance was not significantly different between the two groups. Mean barostat bag volume was 104 +/- 13 mL in fasting aged subjects and 125 +/- 23 mL in controls (NS). After the meal, the barostat bag volume decreased by 69 +/- 11% during 85 +/- 17 min in aged subjects and 75 +/- 14% during 89 +/- 15 min in young controls (NS). Rectal sensory thresholds triggered by distension are increased in aged healthy subjects while compliance and tone are not different. Age should be considered as a confounding factor when studying rectal sensitivity and further studies in aged patients with IBS should include a group of control subjects within the same range of age as studied patients.

Epidemiology and natural history of pelvic floor dysfunction

Pelvic floor dysfunction, including urinary incontinence, anal incontinence, and pelvic organ prolapse, is extremely common, affecting at least one-third of adult women. A minority of patients sustaining these conditions volunteer their symptoms. Risk factor identification and the development of tactics for prevention are significant priorities for future research. Understanding both the specific predisposing factors that place an individual woman at risk and the precise events of the labor and delivery process that initiate injury and dysfunction is important for primary prevention. Defining the relative importance of various promoting and decompensating factors is essential for secondary prevention.

No correlation between perineal position and pudendal nerve terminal motor latency in healthy perimenopausal women

BACKGROUND

Significant associations between perineal descent and pudendal nerve latency have previously been described in fecally incontinent patients. This has led to the hypothesis that pelvic floor muscle and nerve injury initiated by childbirth might progress and cause fecal incontinence.

PURPOSE

The study contained herein was undertaken to test whether changes in perineal position and pudendal nerve latency were associated in a population of healthy middle-aged women.

METHODS

A cross-sectional study of 144 women were selected randomly from the Danish National Register; they had a mean age of 50 (range, 45-57) years and a mean parity of 2 (range, 0-6). Perineal position at rest and during simulated defecation and pudendal nerve terminal motor latency were measured. All examinations were performed by one of the authors (AMR) and without the knowledge of parity.

RESULTS

The perineal position both at rest and during straining was significantly lowered, and the pudendal nerve terminal motor latency was significantly prolonged with increasing numbers of vaginal deliveries (data not shown). There was, however, no association between pudendal nerve terminal motor latency and perineal position at rest (correlation coefficient, r = -0.15, P = 0.1) or during simulated defecation (r = -0.08, P = 0.4).

CONCLUSION

Small but significant effects of vaginal deliveries were detected in a random population of healthy perimenopausal women. However, because perineal descent and pudendal nerve latency were not associated, our findings do not support the hypothesis that damage induced by vaginal delivery to the pudendal nerves and pelvic floor will progress.