THE PRIMARY CARE MANAGEMENT OF CHRONIC CONSTIPATION. Dr Richard Stevens GP in Oxford and editor-in-chief of the Digest and Eurodigest

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1 THE PRIMARY CARE MANAGEMENT OF CHRONIC CONSTIPATION Dr Richard Stevens GP in Oxford and editor-in-chief of the Digest and Eurodigest Introduction Bowel functions are private. When bowels misfunction, privacy can become secrecy, guilt and shame. Constipation is often not taken seriously and perceived as self-inflicted. These feelings of blame, felt by sufferers, compound an existing reluctance to seek help. Constipation is believed to affect around one in every seven adults in the UK. 1 This figure could be an underestimate given the reluctance of people to talk about their bowels. This potentially overlooked condition has both a significant effect on physical and emotional wellbeing, as well as a significant economic footprint on the NHS. If constipation is a ghastly, guilty secret, then faecal incontinence is even more so. The fact that constipation and faecal incontinence co-exist is counter intuitive and often poorly appreciated by both health care professionals and patients. Faecal incontinence affects 1-10% of the general population 2 and in one study, almost half (47%) of men with faecal incontinence described concurrent constipation. 3 Patients feelings of contamination and unworthiness are tangible, and accordingly the condition significantly impacts on quality of life. 2 Chronic constipation can be associated with lifestyle issues as well as long-term co-morbidities. Active investigation, together with a vigilant approach for faecal incontinence, will enable physicians to take a holistic view of the patients predicament. Definition The Rome III consensus provides the most recent definition of functional constipation. Its principle use is to provide consistency across research studies and, although it may therefore be cumbersome for everyday clinical practice, it can be a useful tool in defining what chronic constipation is. Functional Constipation Symptoms 3 months, onset 6 months prior to diagnosis that must include 2 of the following: Straining* Lumpy or hard stools * Sensation of incomplete evacuation * Sensation of anorectal obstruction/blockage * Manual manoeuvres to facilitate defecation (e.g. digital evacuation, support of the pelvic floor) * <3 defecations/week

2 Loose stool rarely present without the use of laxatives Insufficient criteria for IBS-C * 25% of defecations. Rome III also gives a standard definition of irritable bowel syndrome (IBS) where constipation predominates (IBS-C), which requires recognising and distinguishing from functional constipation and of course, different management. Patients sometimes self-declare that they are constipated but do not meet the Rome criteria - self-perceived constipation (SPC). 4 These patients are dissatisfied with their bowel function and seek medical help. Management primarily consists of managing the presenting symptoms, as well as their expectations. At risk groups Certain groups are more at risk of chronic constipation: Women - Are believed to suffer more with chronic constipation (with a 2:1 ratio of women to men affected by the condition). This difference might be exaggerated owing to a greater reluctance of men to seek professional advice. However women may also be at a greater risk of constipation following childbirth where injury to the pelvic floor has occurred. Age - Increasing age is a risk factor for constipation and may be a result of medication, immobility and blunting of the appreciation of the urge to defaecate. High laxative use - as often found in institutionalised patients where diet and low exercise levels may also contribute. Patients with neurogenic bowel dysfunction, for example, spinal cord injury, multiple sclerosis may also suffer from chronic constipation. Causes Although not something that is normally considered, it is important to appreciate that the process of passing a stool involves a coordinated sequence of manoeuvres. This inter-related sequence involves: Relaxation of the puborectalis muscles Descent of the pelvic floor with straightening of the anorectal angle Inhibition of segmental colonic peristalsis Contraction of the abdominal wall muscles Relaxation of the external anal sphincter with expulsion of faeces To arrive in the sigmoid colon and rectum, faeces need to have been propelled along the length of the bowel. This process can be affected by the characteristics

3 of the faeces (low residue, hardness and low bulk), and/or the propulsive mechanisms (slow colonic transit). The former may be affected by diet, water intake and other lifestyle factors. The exact cause of the latter is not known, but it is likely that it is a disorder of the enteric nervous system especially the colonic pacemaker cells (the interstitial cells of Cajal) that regulate the muscular activity of the bowel. 5 Causes of chronic constipation include: Blockages and obstructions colorectal cancer, stricture, compression by an external mass. Painful anal conditions haemorrhoids, fissures. Muscular Pelvic floor weakness, rectocele, rectal prolapse. Endocrine/metabolic thyroid disease, diabetes mellitus, high calcium levels. Psychological/emotional depression, cognitive impairment, habit. Drugs many drugs have constipation as a side-effect. Neurological Multiple sclerosis, Parkinson s disease, autonomic neuropathy, spinal cord injury, cerebrovascular accident, spina bifida. Neurogenic bowel Although most cases of chronic constipation are functional in nature, there remains a significant proportion that experience the condition as a result of nerve damage or deterioration. Bowel function is influenced by the activity of both upper and lower motor neuron pathways and disruption of these produces a different pattern of bowel dysfunction. Neurogenic bowel dysfunction (NBD) is a familiar presence in patients with chronic constipation. Damage to the spinal cord through trauma, or conditions such as Multiple Sclerosis and Parkinson s disease can lead to damage of the nerve tissue innervating the colon and rectum causing NBD. 6

4 Figure 1: Types of patients with NBD. Adapted from Consensus review of best practice of transanal irrigation in adults. 7 There is a direct inverse correlation between the degree of NBD and quality of life. 8 General practitioners will be aware of those patients with spinal injury resulting in hemi- or total paresis, but those that acquire spinal neural damage and problems of a neurogenic bowel through illnesses, especially as comorbidity is also likely. This may be less obvious, owing to an insidious onset, and it is therefore important to be mindful of the possibility, which may not be volunteered, and be prepared to make a direct enquiry. There are two distinct patterns of NBD: Spastic bowel: Interruption of the upper motor neuron pathways - leads to a loss of voluntary control of the bowel but with intact spinal reflexes. This sort of injury leads to constipation, but stimulation of the rectum, either by the presence of stool or the introduction of a stimulant agent in the rectum, leads to spontaneous evacuation. Flaccid bowel: Disruption of lower motor neurons leads to a loss of muscle tone (which can be noted on examination), resulting in constipation with a high risk of faecal incontinence. Careful evaluation allows for distinguishing between types of neurogenic bowel, so individual bowel management plans can be made. A targeted history and examination can differentiate between neurogenic and functional constipation. History and examination

5 A detailed and sensitive history is needed to eliminate the modifiable causes of chronic constipation. Although the majority of cases are likely to result in a label of idiopathic constipation, or the result of modifiable lifestyle issues, this should not always be assumed. The Rome III criteria can be used to distinguish chronic functional constipation from IBS-C and other conditions including self-perceived constipation. Chronic constipation is often present with faecal incontinence. Normal or liquid stool passes round a colonic blockage resulting in overflow diarrhoea. Abdominal, rectal and anal examinations are important particularly to detect faecal impaction and obstruction. A case finding approach should always be employed. Treatable causes, such as faecal impaction, should always be actively managed. Management Constipation and faecal incontinence can be deeply personal issues and management needs to take the patient s needs and preferences into account. Sensitive management and a partnership between doctor and patient are the keys to success. Lifestyle advice Laxatives Adjustments to diet, water intake and activity can help but only when there is a deficiency in them to start with. Notoriously difficult to implement without a good patient-doctor relationship. Bulking agents e.g. ispagula husk. Needs adequate water intake to be effective. Osmotic and softening agents attract fluid into the gut lumen softening the stool e.g. lactulose, Movicol. Stimulant laxatives increase colonic peristalsis e.g. Bisacodyl, docusate, senna. Prucalopride In general, long-term use should be avoided if possible. A relatively new agent that works as a serotonin (5HT) agonist on the enteric nervous system. The NICE guidance suggests it is appropriate for use in women in whom conventional treatments have failed after a six

6 Linaclotide Suppositories, enemas Rectal irrigation Referral to secondary care month trial and in whom invasive procedures are being contemplated. 9 Primarily indicated in IBS-C in the UK. Requires the clinical skill to distinguish from functional constipation. Must be aware of IBS sub types. Rescue treatments that can be effective but are not recommended for longterm management if possible. Rectal irrigation can, after appropriate training, be self-administered thus giving the patient a degree of control and autonomy. Can be a preemptive way of managing severe constipation and faecal incontinence in neurogenic patients. Refractory cases may need specialist input for investigations such as colonoscopy or anal manometry. Treatments such as biofeedback and sacral nerve stimulation may only be available in secondary care. Surgery (e.g. subtotal colectomy) should be the last resort. The pathway of escalating interventions from advice about diet (especially increasing the amount of soluble fibre), exercise and hydration to laxative treatments with osmotic and then stimulant agents is well known to GPs. But around 50% of patients will report treatment failure on laxatives. 10 A number will end up on long-term treatment for which little is known about the long-term effects. Treatment failures need a thoughtful and tailored approach. A patient with, for example slow colonic transit, would not be helped by softening or osmotic laxatives or indeed lifestyle measures - and may have taken these steps themselves before consulting a doctor. Management of severe or refractory constipation Some patients will end up with severe or refractory constipation and require management in primary care. Often these patients have a neurogenic bowel as a result of trauma or disease. Bowel management will be a key element of their care and can take up a considerable amount of nursing time. All the treatments mentioned above could be tried together with; stimulation of the gastrocolic reflex, abdominal massage, digital rectal stimulation and digital evacuation of stool. Personal choice and acceptability are important considerations.

7 Rectal irrigation can play a part in the long-term management of the neurogenic bowel and in severe constipation. With training, rectal irrigation can be selfadministered using a prescribed kit and bowel management can be selfadministered by the patient or carer. Trials have shown an increase in efficacy and improved quality of life with rectal irrigation over conventional therapies. 7,11 NICE guidance recommends transanal irrigation (TAI) when conservative measures have failed on cost efficiency grounds and there are clear benefits for the patients who can then at least maintain a degree of autonomy and dignity. 2 Although the initial product-related costs are relatively high compared to standard therapies, there are longer-term benefits especially when labour and indirect costs are taken into account. 12 TAI should certainly be considered before referral for surgical intervention. Figure 2: Adapted from Consensus Review of Best Practice of Transanal Irrigation in adults. 7 Burden of care Constipation and its attendant problems are common. The economic cost to the NHS for non-elective care for constipation is estimated at 59 million annually. 13 An improvement in the care given through the application of evidence-based measures, combined with a thoughtful approach to any under lying causes rather than a reflex laxative prescription, will provide an opportunity for improving outcomes, reducing costs and improving the patient experience. All of which are of primary interest to commissioners of health care. Summary Constipation is a common problem in primary care. It can often be associated with faecal incontinence of some degree. Shame and stigma surround the area and sensitive, direct questioning may be necessary. Most cases will have functional constipation, but in a significant number there may be a different diagnosis or co-morbidity causing the symptoms. It is important therefore to remain alert to modifiable causes.

8 Poor diet, water intake and immobility should be corrected as far as possible. There is a hierarchy of treatments that can be tried. Self-management and titration of doses against symptoms are goals. For severe and refractory cases the labour costs (usually nursing time) can be high. Self-management with, for example, rectal irrigation systems can free resources as well as promoting self-care and wellbeing. NICE CKS Constipation in adults Set realistic expectations for the results of treatment of chronic constipation. Advise people about lifestyle measures increasing dietary fibre (including the importance of regular meals), drinking an adequate fluid intake, and exercise. Adjust any constipating medication, if possible. Laxatives are recommended: If lifestyle measures are insufficient, or whilst waiting for them to take effect. For people taking a constipating drug that cannot be stopped. For people with other secondary causes of constipation. As 'rescue' medicines for episodes of faecal loading. If laxative treatment is indicated: Start treatment with a bulk-forming laxative. It is important to maintain good hydration when taking bulk-forming laxatives. This may

9 be difficult for some people (for example the frail or elderly). If stools remain hard, add or switch to an osmotic laxative. Use macrogols as first choice of an osmotic laxative. Use lactulose if macrogols are not effective, or not tolerated. If stools are soft but the person still finds them difficult to pass or complains of inadequate emptying, add a stimulant laxative. Adjust the dose, choice, and combination of laxative according to symptoms, speed with which relief is required, response to treatment, and individual preference. The dose of laxative should be gradually titrated upwards (or downwards) to produce one or two soft, formed stools per day. If at least two laxatives (from different classes) have been tried at the highest tolerated recommended doses for at least 6 months, consider the use of prucalopride in women only. References 1. NHS Choices. Constipation. Constipation at < 2. NICE. Faecal incontinence: The management of faecal incontinence in adults CG49). (2007). 3. Burgell, R. E., Bhan, C., Lunniss, P. J. & Scott, S. M. Fecal Incontinence in Men: Coexistent Constipation and Impact of Rectal Hyposensitivity. Dis. Colon Rectum 55, (2012). 4. Bellini, M. et al. Management of chronic constipation in general practice. Tech. Coloproctology 18, (2014). 5. Frattini, J. & Nogueras, J. Slow Transit Constipation: A Review of a Colonic Functional Disorder. Clin. Colon Rectal Surg. 21, (2008). 6. Hinds, J. P., Eidelman, B. H. & Wald, A. Prevalence of bowel dysfunction in multiple sclerosis. A population survey. Gastroenterology 98, (1990).

10 7. Emmanuel, A. V. et al. Consensus review of best practice of transanal irrigation in adults. Spinal Cord 51, (2013). 8. Krogh, K. et al. Colorectal function in patients with spinal cord lesions. Dis. Colon Rectum 40, (1997). 9. NICE. Prucalopride for the treatment of chronic constipation in women. (2010). 10. Johanson, J. F. & Kralstein, J. Chronic constipation: a survey of the patient perspective. Aliment. Pharmacol. Ther. 25, (2007). 11. Christensen, P. et al. A randomized, controlled trial of transanal irrigation versus conservative bowel management in spinal cord-injured patients. Gastroenterology 131, (2006). 12. Christensen, P., Andreasen, J. & Ehlers, L. Cost-effectiveness of transanal irrigation versus conservative bowel management for spinal cord injury patients. Spinal Cord 47, (2009). 13. Data on file. Hospital Episodic Statistical data 2012/2013.