Constipation and Weight Loss

Question 1

Social risk factors for constipation

Answer 1

-Low fibre diet or low calorie intake.
-Difficult access to toilet, or changes in normal routine or lifestyle.
-Lack of exercise or reduced mobility.
-Limited privacy when using the toilet.
-Low educational levels or socio-economic deprivation.
-A family history of constipation.

Question 2

Psychological risk factors for constipation

Answer 2

-Anxiety and/or depression.
-Somatization disorders.
-Eating disorders.
-History of sexual abuse

Question 3

Physical risk factors for constipation

Answer 3

-Female sex.
-Older age.
-Pyrexia, poor fluid intake/dehydration, immobility.
-Sitting position on a toilet seat (compared with the squatting position for defecation)

Question 4

Definition of constipation

Answer 4

-Defecation that is problematic because of infrequent and/or hard stools, difficulty passing stools (often involving straining), or the sensation of incomplete emptying or anorectal blockage.

-The Rome IV diagnostic criteria for constipation include spontaneous bowel movements occurring fewer than three times a week.

-Stools are often dry, hard, or lumpy, and may be abnormally large or small. Excessive straining, lower abdo pain, discomfort, distention, bloating

-In practice constipation is often defined as passage of stools less frequently than the person’s normal pattern/ defecation that is unsatisfactory because of infrequent stools (< 3 times weekly), difficult stool passage (with straining or discomfort), or seemingly incomplete defecation.

Question 5

Definition of chronic constipation

Answer 5

Symptoms which are present for at least three months.

Question 6

Definition of faecal loading/ impaction

Answer 6

Retention of faeces to the extent that spontaneous evacuation is unlikely

Question 7

Definition of overflow faecal incontinence

Answer 7

Leakage of liquid stool from the proximal colon around impacted faeces, where small quantities of stool may be passed frequently and without sensation

Question 8

Definition of function (primary or idiopathic) constipation

Answer 8

Chronic constipation without a known cause
=Dssynergistic defaecation
=Slow transit
=IBS

Question 9

Definition of dyssynergistic defaecation

Answer 9

Paradoxical contraction or inadequate relaxation of pelvic floor muscles during defecation.

Question 10

Definition of slow transit constipation

Answer 10

Prolonged delay in passage of stool through the colon and/or poor propulsion during defecation

Question 11

Definition of secondary/ organic constipation

Answer 11

Constipation caused by medication or an underlying medical condition, including endocrine, metabolic, neurological or primary diseases of the colon, for example stricture, malignancy, or proctitis

Question 12

Prevalence of constipation

Answer 12

-2-3x higher in women
-More common in elderly
-Higher prevalence in institutional settings (nursing homes and hospital)
-More common in pregnancy
-2x likely in black patients and deprived socio-economic groups

Question 13

Medications causing secondary constipation

Answer 13

-Aluminium-containing antacids; iron or calcium supplements.
-Analgesics, such as opiates (up to 80% of patients, even with concomitant use of laxatives) and nonsteroidal anti-inflammatory drugs (NSAIDs).
-Antimuscarinics, such as procyclidine and oxybutynin.
-Antidepressants, such as tricyclic antidepressants.
-Antipsychotics, such as amisulpride, clozapine, or quetiapine.
-Antiepileptic drugs, such as carbamazepine, gabapentin, oxcarbazepine, pregabalin, or phenytoin.
-Antihistamines, such as hydroxyzine.
-Antispasmodics, such as dicycloverine or hyoscine.
-Calcium-channel blockers, such as verapamil.
-Diuretics, such as furosemide

Question 14

Organic causes of secondary constipation

Answer 14

-Endocrine and metabolic diseases
-Myopathic conditions
-Neurological conditions
-Structural abnormalities
-Other

Question 15

Endocrine and metabolic diseases causing secondary constipation

Answer 15

-Diabetes mellitus (with autonomic neuropathy)
-Hypercalcaemia and hyperparathyroidism.
-Hypermagnesaemia.
-Hypokalaemia.
-Hypothyroidism
-Uraemia

Question 16

Myopathic conditions causing secondary constipation

Answer 16

-Amyloidosis.
-Myotonic dystrophy.
-Scleroderma

Question 17

Neurological conditions causing secondary constipation

Answer 17

-Autonomic neuropathy.
-Cerebrovascular disease
-Hirschsprung’s disease
-Multiple sclerosis.
-Parkinson’s disease
-Spinal cord injury, tumours

Question 18

Structural abnormalities causing secondary constipation

Answer 18

-Anal fissures, strictures, haemorrhoids
-Colonic strictures (for example following diverticulitis, ischaemia, or surgery).
-Inflammatory bowel disease
-Obstructive colonic mass lesions (for example due to colorectal cancer)
-Rectal prolapse or rectocele.
-Postnatal damage to pelvic floor or third-degree tear

Question 19

Other causes of secondary constipation

Answer 19

-IBS
-Slow transit constipation
-Pelvic or anal dyssynergia

Question 20

Complications of chronic constipation

Answer 20

-Faecal loading and impaction.
-Progressive faecal retention, distension of the rectum, and loss of sensory and motor function.
-Overflow diarrhoea
-Acute urinary retention
-Haemorrhoids or anal fissure.

Question 21

Complications of chronic faecal loading and impaction

Answer 21

-Faecal incontinence, which can be embarrassing and distressing.
-Chronic dilatation of the colon may cause megacolon.
-Bowel obstruction, perforation, or ulceration.
-Recurrent urinary tract infections, obstructive uropathy.
-Rectal bleeding.
-Rectal prolapse.

Question 22

Non-specific symptoms of constipation in elderly

Answer 22

-Confusion or delirium, functional decline.
-Nausea or loss of appetite.
-Overflow diarrhoea.
-Urinary retention

Question 23

History suggesting faecal loading or impaction

Answer 23

-Hard, lumpy stools, which may be large and infrequent (for example passed every 7–10 days), or small and relatively frequent (for example passed every 2–3 days).
-Having to use manual methods to extract faeces.
-Overflow faecal incontinence, or loose stool

Question 24

Questions to ask in context of constipation

Answer 24

-Red flags: sudden change in bowel habit, rectal bleeding or bloody stools, weight loss, abdominal pain, IDA
-What the person means by constipation and normal pattern of defecation
-Duration, frequency, consistency (Bristol Stool Chart), nocturnal symptoms
-Associated symptoms (rectal discomfort, excessive straining, feeling incomplete evacuation or blockage, rectal bleeding, abdominal pain or distention)
-Fever, nausea, vomiting, weight loss, appetite
-Urinary symptoms (incontinence, retention, dyspareunia)
-History of colorectal cancer/IBD
-How symptoms affect quality of life and daily functioning, self-help measures

Question 25

Questions to assess risk factors in constipation

Answer 25

-Diet (fibre, fluid intake)/ lifestyle/ level of activity/ mobility
-Toileting habits (feeling hurried or being disturbed when trying to defecate; withholding or ignoring the urge to defecate; access to the toilet at home or work, and level of privacy)
-Associated psychological or mental health conditions
-Any drug treatment or clinical features of an underlying organic cause of secondary constipation, and manage appropriately

Question 26

Questions to assess faecal loading/ impaction

Answer 26

-A history of faecal incontinence, for example is underwear regularly soiled, excessive wiping, or loose stools.

-Whether the person has needed to use manual measures to relieve constipation:
=A finger having to be inserted into the vagina suggests a rectocele.
=A finger in the rectum to push away a flap suggests a rectal ulcer.
=Pressure behind the anus may assist defecation if the levator muscles are weak.
=Digital rectal evacuation of faeces confirms severe faecal loading and/or impaction

Question 27

Examination in constipation

Answer 27

-Assess for signs of weight loss and general nutritional status.
-Perform an abdominal examination to check for abdominal pain, distension, masses, or a palpable colon (suggesting retained faecal masses).
-Perform a digital rectal examination

Question 28

What is checked in a PR examination in constipation?

Answer 28

-Anal fissures, haemorrhoids, skin tags, rectal prolapse, rectocele, skin erythema or excoriation (this may be a sign of faecal leakage).
-Resting anal sphincter tone; rectal mass lesions and retained faecal masses, which may also be felt on external peri-anal palpation. Note: a faecal mass can be distinguished from a tumour or cyst, as firm pressure exerted by a finger will typically leave a palpable indentation in hard faeces.
-Pelvic floor dysfunction (if appropriate) — while asking the person to ‘bear down’, there may be paradoxical contraction of the anal sphincter on straining.
-Leakage of stool; rectal or anal pain

Question 29

Overview in management of constipation

Answer 29

-Investigate and exclude any secondary causes, consider red flag symptoms
-Exclude any faecal impaction
-Advice on lifestyle measures
=Increasing dietary fibre
=Ensuring adequate fluid intake
=Ensuring adequate activity levels
-First-line laxative: bulk-forming laxative first-line, such as ispaghula
-Second-line: osmotic laxative, such as a macrogol

Question 30

Initial self-management advice for constipation

Answer 30

-Eating a healthy, balanced diet and having regular meals:
=whole grains, fruits (and their juices) high in sorbitol, and vegetables.
=Food Fact Sheets
=Fibre intake should be increased gradually (to minimize flatulence and bloating) — adults should aim to consume 30 g of fibre per day.
=Drinking an adequate fluid intake, especially if there is a risk of dehydration.

-Increasing activity and exercise levels, if these are below the national recommended levels.

-Helpful toileting routines:
=Advise on a regular, unhurried toilet routine, giving time to ensure that defecation is complete.
=Advise on responding immediately to the sensation of needing to defecate.
=Ensure that people with limited mobility have appropriate help to access the toilet and adequate privacy.
=Ensure the person has access to supported seating if they are unsteady on the toilet.

Question 31

Management of short-duration constipation (less than 3 months)

Answer 31

-Faecal impaction= enemas, suppositories or disimpaction.

-Advise on lifestyle measures, such as increasing dietary fibre, ensuring adequate fluid intake, and activity levels.

-Oral laxatives using a stepped approach:
=Bulk-forming laxative first-line, such as ispaghula.
-If stools remain hard or difficult to pass, add or switch to an osmotic laxative, such as a macrogol.
=If a macrogol is ineffective or not tolerated, offer treatment with lactulose second-line.
=If stools are soft but difficult to pass, or there is a sensation of inadequate emptying, add a stimulant laxative.

-If the person has opioid-induced constipation:
=Do not prescribe bulk-forming laxatives.
=Offer an osmotic laxative and a stimulant laxative.
=Advise the person to gradually reduce and stop laxatives once the person is producing soft, formed stool without straining at least three times per week.

Question 32

Management of chronic constipation

Answer 32

-Same as short-duration
-Consider treatment with prucalopride if at least two laxatives from different classes have been tried at the highest tolerated recommended doses for at least 6 months, and failed to relieve symptoms, where invasive treatment (such as suppositories, enemas, rectal irrigation and/or manual disimpaction) is being considered.

Question 33

Mechanism of action of prucalopride

Answer 33

The prokinetic prucalopride (a selective, high-affinity, serotonin [5HT4] receptor agonist) stimulates gastrointestinal motility

Question 34

Management of faecal loading/ impaction

Answer 34

-If there are hard stools, consider prescribing a high dose of an oral macrogol.
-If there are soft stools, or ongoing hard stools after a few days of treatment with an oral macrogol, consider starting or adding an oral stimulant laxative.

-If the response to oral laxatives is inadequate or too slow, consider prescribing:
=A suppository such as bisacodyl for soft stools; glycerol alone, or glycerol plus bisacodyl for hard stools.
=A mini enema such as docusate (softener and weak stimulant) or sodium citrate (osmotic).

=A sodium phosphate or arachis oil retention enema (placed high if the rectum is empty but the colon is full).
=For hard stool it can be helpful to give the arachis oil enema overnight before giving a sodium phosphate (large volume) or sodium citrate (small volume) enema the next day.
=Enemas may need to be repeated several times to clear hard, impacted faeces.

Question 35

Reasons for reduced energy intake in weight loss

Answer 35

-Malabsorption
-Psychiatric causes
-Loss of appetite

Question 36

Reasons for increased energy expended in weight loss

Answer 36

-Malignancy
-Chronic inflammatory conditions
-Organ failure

Question 37

Management of weight loss

Answer 37

-Dietary advice
-Oral nutritional supplements
-NG feeding
-PEG feeding
-PEJ
-Jejunostomy
-TPN

Question 38

Laxative advice

Answer 38

-Laxatives should not be stopped suddenly, and weaning may take several months. The rate of laxative dose reduction should be guided by the frequency and consistency of stools.
-Laxative doses should be reduced gradually, for example after 2–4 weeks when regular bowel movements are comfortable, with soft formed stools.
=This is to minimize the risk of requiring rescue laxative treatment for recurrent faecal loading and/or impaction.
=If a combination of laxatives has been used, reduce and stop one laxative at a time, starting with stimulant laxatives, if possible. Note: it may be necessary to also adjust the dose of other laxatives used to maintain regular bowel movements.
-Relapses are common and should be treated early with increased doses of laxatives.
-Laxatives may need to be continued long term for people with a medical condition or taking a medication (if it cannot be reduced or stopped) causing secondary constipation.