Causes of Constipation

Main Point Constipation is a SYMPTOM Constipation is not a diagnosis

Definition Persistent, difficult, infrequent or seemingly incomplete defaecation Normal frequency ? - variable – 3 times per day to once per 3 days Normal consistency ? – Excessive straining, hard stools, lower abdominal fullness, sense of incomplete evacuation – Subjective Psychosocial factors

Causes How many can you think of ??? Subdivide into Recent and Chronic

Recent Constipation A recent and persistent change in bowel habit needs to be investigated unless there is an obvious cause (new drug, illness etc) Especially if – Older person – Excessive straining, feeling of incomplete emptying – Anaemia / rectal bleeding

Recent Constipation Colonic Obstruction – Neoplasm – Stricture – Ischaemia – Diverticular – Inflammatory

Recent Constipation Anal Sphincter Spasm – Anal fissure – Painful haemorrhoids Medications – Suggestions? Situational – Illness, bedfast, immobile, hospitalisation – Terminal reservoir syndrome / faecal impaction

Chronic Constipation Bowel Irritable bowel syndrome – Constipation predominant, alternating Slow transit Rectal evacuation disorders – Pelvic floor dysfunction – Anismus – Rectal mucosal prolapse – Rectocoele

Irritable Bowel Syndrome Chronic abdominal pain Altered bowel habit No apparent cause Other symptoms – GI: Dyspepsia, nausea, bloating, excess gas, pain – Urinary sx, fibromyalgia sx, sexual dysfunction All age groups; F:M = 2:1

Chronic Constipation Bowel Irritable bowel syndrome – Constipation predominant, alternating Slow transit Rectal evacuation disorders – Pelvic floor dysfunction – Anismus – Rectal mucosal prolapse – Rectocoele

Chronic Constipation Neurological - Central Parkinson’s Disease Multiple Sclerosis Spinal cord injury Neurological – Peripheral Diabetes Mellitis Autonomic neuropathy

Chronic Constipation Endocrine Hypothyroidism / Panhypopituitism Hypercalcaemia Hypokalaemia Pregnancy (but not in Older People)

Chronic Constipation Psychiatric Depression Eating disorders, anorexia nervosa Muscle Systemic sclerosis (Scleroderma) Myotonic dystrophy

Medications Analgesics – Paracetamol, Codeine, Opioids Anticholinergics – Antidepressants (Amitriptylline) – Antipsychotics (Chlorpromazine) – Parkinson’s disease drugs – Oxybutinin Antihistamines Antispasmodics

Medications Cations – Aluminium, Iron, Bismuth Antihypertensives – Calcium channel blockers (Verpamil) Cancer Drugs Chronic laxative abuse

Older People Diet – – Reduced caloric intake – Reduced fibre and fluid? Poor dentition Reduced mobility / exercise Less perception of rectal fullness Chronic illness: less mobile / more bed rest Dementia

“Alarm” Features Weight loss (> 5 kg) Rectal bleeding / Anaemia Electrolyte abnormalities Raised inflammatory markers Family Hx: – Carcinoma colon – Inflammatory Bowel Disease

Summary No cause in >90% patients who complain of chronic constipation Severe intractable constipation in <5% – Need more detailed assessment Constipation is a symptom not a diagnosis – Keep alert for “Alarm Features”