Diagnosis of constipation in family practice

Patients who complain of constipation to their family doctor may not be truly constipated. Variability in stool frequency and consistency, and perception of symptoms may lead to inaccurate patient reporting or diagnosis of constipation.

To determine whether patients visiting their family doctor with a complaint of, or diagnosed with, constipation fulfilled the Rome II criteria for functional constipation and had stool characteristics of constipation.

A random sample of Canadian family physicians were recruited to enroll a series of adults who complained of, or had received a diagnosis of, constipation during an office visit. Patients were advised of the survey. Those providing written consent were contacted by an independent research firm and forwarded a survey questionnaire that included the Rome II gastrointestinal questionnaire, questions regarding their medical history and questions regarding their demographics. Patients also completed a four-week daily diary recording their bowel habits using the Bristol Stool Form Scale, medication use and satisfaction with treatment. Questionnaire and diary responses were retrieved by telephone.

One hundred eighty-four family physicians enrolled 311 patients, of whom 220 completed the questionnaire. Females comprised 79.5% of the sample and had a mean age of 54.2 years (males 61.6 years; P<0.05). According to the Rome II criteria, 37.3% had functional constipation and 46.8% had irritable bowel syndrome (IBS). Whole gut transit times estimated using the Bristol Stool Scale were similar among those with self-reported constipation, those with Rome II functional constipation and those with Rome II IBS (79.3 h, 85.8 h and 77.4 h, respectively). Almost half of the patients with IBS or functional constipation were taking a pain medication, while nearly one-fifth took antidepressants. Of the medications or remedies taken to treat constipation, patients rated 49.8% of the doses as satisfactory.

A large proportion of Canadian primary care patients whose presenting complaint or diagnosis was constipation satisfied the Rome II criteria for IBS, with a smaller number defined as functionally constipated. IBS patients tended to be younger than those with functional constipation, and whole gut transit times did not differentiate IBS from functional constipation. Careful questioning of patients who complain of constipation may reveal constipating medication, diarrhea symptoms or IBS.