Constipation: When is it life-threatening?

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Constipation is seldom serious, but can be uncomfortable and frustrating. (Thinkstock photo)

Constipation is one of the most common digestive complaints worldwide, with everyone getting constipation at some time in their lives. Though not usually serious, it can nonetheless be uncomfortable and frustrating. In the USA alone, constipation affects 2 per cent of the adult population, accounting for up to 2.5 million doctor visits annually and medication costs worth millions of dollars.

A local study published in the Singapore Medical Journal in 2000 showed constipation affected about 7.3 per cent of people aged 16 years and above.

What is constipation?

Constipation is a symptom and not a disease in itself. Constipation occurs when bowel movements become difficult or less frequent. The normal length of time between bowel movements ranges widely from person to person, but generally when movements stop for more than three days, the stools or faeces become harder and more difficult to pass. Patients may experience abdominal bloating, cramping pain or even vomiting.

Although definitions vary, one is considered constipated if there are two or fewer bowel movements in a week, or if one has two or more of the following symptoms for at least three months:

  1. Straining during a bowel movement more than 25 per cent of the time
  2. Hard stools more than 25 per cent of the time
  3. Incomplete evacuation more than 25 per cent of the time

What causes constipation?

There are numerous causes of constipation and it is not always possible to identify a definite cause in each patient. The majority of patients can be managed conservatively and the doctor’s vital role is to identify more serious causes that might require surgical treatment. Causes may include:

  • Dietary disturbances (inadequate water intake, too little or too much dietary fibre, disruption of regular diet or routine)

Related article: Are fibre supplements as good as fibre-rich foods?

  • Inadequate activity/exercise or immobility
  • Excessive/unusual stress
  • Medical conditions: hormonal (hypothyroidism), neurological (stroke, Parkinson’s disease), depression, eating disorders
  • Medications (antacids containing calcium or aluminium, strong pain medicines like narcotics, anti-depressants, iron pills)
  • Pregnancy
  • Colon cancer

Related article: 7 tips to lower your risk of colon cancer

When is constipation a cause for serious concern?

Most people do not need extensive testing. Only a small number of patients with constipation have a more serious underlying problem. Symptoms that could point to more serious causes that warrant early attention include:

  • Constipation that is a new problem for you.
  • Your constipation has lasted more than two weeks.
  • You have blood in your stools.
  • You are losing weight even though you are not dieting.
  • Your bowel movements are associated with severe pain.
  • You are more than 50 years of age with a family history of colorectal cancer.

The vast majority of patients with constipation do not have any obvious underlying illness (secondary constipation) to explain their symptoms, and they suffer from one of two types of functional constipation (primary constipation):

  1. Colonic inertia: A condition in which the colon contracts poorly and retains the stools.
  2. Obstructed defecation: A condition in which a person excessively strains to expel the stools from the rectum. This may be due to a lack of coordinated anal muscle contractions or structural problems like rectal prolapse or a combination of both.

Nonetheless, these problems can be difficult to manage and can significantly affect one’s quality of life. Occasionally, functional constipation may be part of a more complex pelvic floor disorder. As such, even after excluding more life-threatening causes like cancer, persistent constipation should not be neglected and patients can still benefit from specialist help.

Related article: Have you tried laxatives and fibre drinks but only felt more bloated and uncomfortable?

Public Forum: Find out how to “Stay in Control” by attending the SGH public forum on pelvic floor disorders on Saturday, 26 October 2013, 1-5pm. Topics include constipation, faecal/urinary incontinence and womb/vaginal prolapse. Venue: Suntec City Convention Centre, Level 3, Seminar Rooms 300-302. Entrance fee: $5/pax. To register, please call 6576-7658 or 6326-5151 from 10:30am-5:30pm, Monday-Friday, or email by 23 October 2013.

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By Dr Mark Wong, Director, SGH Pelvic Floor Disorders Service, a member of the SingHealth group, for

Health Xchange's articles are meant for informational purposes only and cannot replace professional surgical, medical or health advice, examination, diagnosis, or treatment.