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Introduction

Constipation is a common, frequently encountered gastrointestinal disorder affecting approximately one third of adults 60 years and older, with over half of nursing home residents affected. Constipation can have significant consequences: in susceptible and frail older people, excessive straining can trigger a syncopal episode and coronary or cerebral ischaemia. In severe cases, constipation can lead to anorexia, nausea and pain and ultimately can cause a stercoral ulcer, leading to perforation and death. Stercoral ulcers are due to hard, impacted faeces causing pressure necrosis of the distal colon, leading to ulceration and subsequent perforation of the intestinal wall.

Constipation often causes a reduction in the quality of life, with general health, vitality, social functioning and mental health all affected. Risk factors for constipation include female sex, older age, inactivity, low calorie intake, a low-fibre diet, polypharmacy, and low income. The incidence of constipation is three times higher in women, and women are twice as likely as men to see their primary care team for constipation.

Symptoms

Patients usually complain of ‘straining’ when opening their bowels, difficulty passing stools, incomplete evacuation or both. This is often associated with hard stools, abdominal bloating pain and distention. The stool frequency may be normal.

Primary constipation

Primary constipation includes the subtypes of normal transit, slow transit and disorders of defaecation, all of unknown causes. Histology of the colon of older adults shows more tightly packed collagen fibres and a reduced number of myenteric neurons, but these changes are not considered to be major contributors to the development of constipation.

Secondary constipation

Secondary causes of constipation include medication use, chronic disease processes and psychosocial issues. Opioids, calcium channel blockers, oral iron supplements, antacids and anticholinergics are common causes for medication-induced constipation, while hypothyroidism, hypercalcaemia, Parkinson’s disease and colorectal carcinoma can all cause secondary constipation.

Assessment

Patients should always be assessed for red flags that might indicate an underlying malignancy, such as:

·       persistent unexplained change in bowel habits

·       palpable mass in the lower right abdomen or the pelvis

·       persistent rectal bleeding without anal symptoms

·       narrowing of stool calibre

·       family history of colon cancer, or inflammatory bowel disease

·       unexplained weight loss, iron deficiency anaemia, fever, or nocturnal symptoms

·       severe, persistent constipation that is unresponsive to treatment.

NICE guidance NG12 gives primary care practitioners a clear framework when to refer a patient with suspected colorectal cancer on a two week wait (2ww) suspected cancer pathway referral.

When evaluating an older individual with constipation, taking a thorough drug and medical history and performing a physical examination are important. Abdominal examination might reveal abnormal bowel sounds, significant weight loss, cachexia, masses and/or sigmoid or colonic loading. When planning a rectal examination, the patient should be informed about its diagnostic importance and the fact that it might be uncomfortable. A chaperone should always be offered and consent documented. Examination of the anus might reveal abnormalities such as proctitis, haemorrhoids, prolapse, fissures or rectal cancer, while further up in the ampulla a rectal-digital examination can detect faecal impaction, masses, and gives the examiner the chance to evaluate anal tone.

Management

Non-pharmacological treatment is often the first step to help patients in the management of their complaint with adaptation of the patients’ medication a start to reduce symptoms.

Endocrinological/psychological/neurological causes of secondary constipation will need investigation and appropriate management. It might be worth discussing with the patient that there is no physiological necessity to have a daily bowel motion: a discussion around simple lifestyle changes might improve their perception of bowel regularity and a diary reporting on stool pattern and consistency may be helpful as well. The optimal time to have a bowel movement is often after waking and/or after meals, when the colon’s motor activity is particularly pronounced. A gradual increase in the intake of fluids and fibre should be suggested, but we should be careful in patients with cardiorenal issues not to cause overloading. A prospective study from Japan found that placing the patient’s feet on a small foot stool in front of the toilet, in conjunction with the upper body bent forward, improved anal pressure and reduced time of evacuation. Patients in care homes should be given adequate time and privacy for their bowel movements and should avoid bed pans.

Most patients will, at one stage, require a laxative to alleviate their symptoms when lifestyle interventions are ineffective: in patients with short-duration constipation a bulk forming laxative such as ispaghula husk should be initiated. If these are not helpful, an osmotic laxative such as macrogol should be next.

In chronic constipation, a bulk forming laxative should be initiated, with adequate hydration ensured (low fluid intake with bulk forming laxatives can cause impaction). If defaecation continues to be unsatisfactory, an osmotic laxative should be the next choice, with the addition of a stimulant laxative such as bisacodyl if the patient doesn’t improve. Once regular bowel movements occur, the laxatives can be slowly withdrawn.

If there is no response to the maximum tolerated dose of second line laxatives, refer to the local GI or older people’s outpatient team, or ask for guidance via the local advice and guidance process.

If the patient presents with faecal impaction, the appropriate escalating dose of a macrogol should be considered. In those with soft stools, or with hard stools after a few days’ treatment with a macrogol, an oral stimulant laxative should be started or added to the previous treatment. If the response continues to be underwhelming, rectal administration of bisacodyl (for soft stools) or glycerol (for hard stools) can be considered.

If there is still no response, a sodium acid phosphate with sodium phosphate enema may have to be considered. For hard stools, an overnight arachis oil enema, followed by a sodium acid phosphate with sodium phosphate enema the next morning might prove effective.

In patients with opioid-induced constipation, an osmotic laxative (or docusate sodium to soften the stools) and a stimulant laxative is recommended. Bulk-forming laxatives should be avoided.

If the patient’s presentation is getting worse or there is no response, then consult with one of your colleagues from gastroenterology. Further input from these teams might be needed for additional pharmacotherapy, endoscopy, anorectal manometry or other secondary/tertiary care investigations.

References:

Arco, S; Saldaña, E et al (2021). Functional Constipation in Older Adults: Prevalence, Clinical Symptoms and Subtypes, Association with Frailty, and Impact on Quality of Life. Gerontology DOI: 10.1159/000517212

British National Formulary: Constipation https://bnf.nice.org.uk/treatment-summaries/constipation/ accessed 14/7/2022

Gandell, D; Straus, SE et al (2013). Treatment of constipation in older people. Canadian Medical Association Journal, May 14, 185(8) DOI:10.1503/cmaj.120819

De Giorgio, R; Ruggeri, E et al (2015). Chronic constipation in the elderly: a primer for the gastroenterologist. BMC Gastroenterology 15:130 DOI 10.1186/s12876-015-0366-3

Gough, AE; Donovan, MN et al (2016). Perforated Stercoral Ulcer: A 10-year experience. Journal of the American Geriatrics Society.  Vol 64, No 4

Heidelbaugh, J; Martinez de Andino, N et al (2021). Diagnosing Constipation Spectrum Disorders in a Primary Care Setting. Journal of Clinical Medicine. (10) 1092. https://doi.org/10.3390/jcm10051092

Hull and East Riding Prescribing Committee (2019). Management of Constipation in Adults. https://www.hey.nhs.uk/wp/wp-content/uploads/2019/08/GUIDELINE-Constipation-guidelines-updated-may-19.pdf accessed 14/7/2022

Jamshed, N; Lee, Z; Olden, KW (2011). Diagnostic Approach to Chronic Constipation in Adults. American Family Physician. 84(3):299-306

Mounsey, A; Raleigh, M et al (2015). Management of Constipation in Older Adults. American Family Physician Volume 92, Number 6

National Institute for Health and Care Excellence (2021).  NG12 Suspected cancer: recognition and referral. https://www.nice.org.uk/guidance/ng12/chapter/Recommendations-organised-by-site-of-cancer#lower-gastrointestinal-tract-cancers accessed 14/7/2022

Rome Foundation (2016) Appendix A: Rome IV Diagnostic Criteria for FGIDs. https://theromefoundation.org/rome-iv/rome-iv-criteria/ accessed 14/7/2022

Schuster, BG; Kosar, L et al (2015). Constipation in older adults; Stepwise approach to keep things moving. Canadian Family Physician 61: February

Takano, S; Nakashma, M et al (2018). Influence of foot stool on defecation: a prospective study. Pelviperineology 2018; 37: 101-103

Villanueva Herrero JA, Abdussalam, A et al (2022). Rectal Exam. In StatPearls. StatPearls Publishing. https://pubmed.ncbi.nlm.nih.gov/30726041/