Management of Chronic Constipation: Guidelines From the American Society of Colon and Rectal Surgeons

Constipation is one of the most common gastrointestinal disorders, with a worldwide prevalence of 15%. Risk factors include inactivity, low socioeconomic status, low-fiber diet, female sex, age older than 65 years, and non-White race. The American Society of Colon and Rectal Surgeons published guidelines for the management of chronic constipation.

A directed history and physical examination should be performed for patients with constipation. This initial evaluation focuses on ruling out serious diseases and involves asking about rectal bleeding, blood in the stools, change in the caliber of stools, weight loss, anemia, or family history of colorectal cancer. Endoscopic evaluation should be performed if red flag signs and symptoms are present.

If no red flag signs or symptoms are present, the frequency and consistency of bowel movements and associated symptoms should be assessed. Infrequent hard stools are likely due to colonic inertia; incomplete evacuation and straining suggest pelvic floor dysfunction; and abdominal pain suggests irritable bowel syndrome. Physicians should ask about symptoms that suggest pelvic floor dysfunction, such as dyspareunia and urinary symptoms. History of sexual assault or an eating disorder should also be considered. Other symptoms could suggest psychiatric, neurologic, or endocrine disorders that are associated with constipation.

Physicians should address modifiable behavioral factors (eg, diet, dehydration, immobility). Medications that can contribute to constipation include opioids, antidepressants, anticholinergics, calcium channel blockers, and calcium supplements.

The physical examination should evaluate for palpable abdominal masses that could cause constipation due to extrinsic compression. External anal inspection can demonstrate distorted anatomy or a bulky neoplasm. Digital rectal examination can reveal anal hypotonia, paradoxical puborectalis contraction, rectocele, anorectal mass, stricture, or fecal impaction. Evaluating the pelvic descent and puborectalis function with a Valsalva maneuver should be considered. Anoscopy or rigid proctoscopy can help evaluate for internal hemorrhoids, proctitis, or masses.

Physicians should consider laboratory tests to rule out hypothyroidism, hyperparathyroidism, and diabetes. Patient-rated scales can be used to assess the nature, severity, and impact of constipation and to monitor constipation over time.

Initial Management

Dietary modification with increasing water and fiber consumption are first-line treatment and typically should be completed before investigations of motility and pelvic floor function. Increasing fiber in the diet is better tolerated than fiber supplementation or laxatives, and studies have shown a benefit to combined soluble and insoluble fiber as well as oat bran. Fiber is most effective in patients with normal transit constipation, with 85% experiencing symptomatic improvement. Up to 80% of patients with slow colonic transit and 63% with constipation secondary to outlet obstruction will not benefit from dietary interventions alone. Fiber supplementation improves symptoms in irritable bowel syndrome with constipation and restores gut microbiota to be consistent with patients without constipation.