Smoking Linked to Abdominal Pain for Irritable Bowel Syndrome Patients

Sara Rurgo, MD

Patients with irritable bowel syndrome who also smoke are at an increased risk of severe abdominal pain according to new research.

A team, led by Sara Rurgo, MD, Department of Clinical Medicine and Surgery, University of Naples “Federico II,” examined how smoking impacts abdominal pain and colonic transit for patients with IBS.

Smoking and IBS

There are several reasons why smoking has been linked to chronic pain for patients with a variety of diseases because smoking modulates the autonomic function and it delays mouth to cecum transit time.

IBS is often linked to altered colonic motility and sensation. And while smoking can impact pain perfection and is a risk factor for post-infectious IBS, there is not much research on the effect of smoking on abdominal pain and colonic transit in patients with IBS.

“It could be speculated that smoking may increase the risk or worsen the course of IBS, since a negative effect of smoking on gastrointestinal functions, especially colonic motility, has been documented,” the authors wrote. “On the other hand, some effects of smoking on colonic function may even reinforce tobacco use in patients with IBS. More than half of patients with IBS–constipation subtype or chronic constipation who smoke, attribute a stool-softening effect to cigarette smoking.”

Study Participants

Overall, there were 40 patients with IBS with constipation (IBS-C) and 28 patients with mixed bowel habit (IBS-M) included in the study based on the Rome IV criteria. Of the 68 patients, 48 were women and the median age was 38 years.

The team identified smoking habits using a dedicated interview, in which patients were classified has habitual smokers if they consumed more than 10 cigarettes per day for more than 3 years.

The investigators recorded the presence of mild or severe abdominal pain and the prevalence of pain characteristics including diffused or localized, chronic or acute, and with cramps or gradually distending.

The team also used univariate and stepwise multiple logistic regression analysis for the data to verify the risk association between pain and all other variables.

Pain Severity

The results show patients with IBS-C had a longer transit time in the right colon, while scoring more chronic pain in comparison to patients with IBS-M.

In addition, more male patients and more smokers reported severe pain (16/30 vs. 4/38 and 20/30 vs. 4/38; both P <0.001).

After conducting the multivariate analysis, the investigators confirmed that smoking was an independent risk factor for severe abdominal pain (OR, 14.3; 95% CI, 2–99, P = 0.007).

However, smoking was not linked to colonic transit times and colonic transit was not associated with IBS symptom severity (both P = N.S.).

“Smoking was the only factor independently associated with severe abdominal pain,” the authors wrote. “As smoking does not seem to affect colonic transit time, we suggest that smoking may influence visceral perception and symptoms severity in IBS patients.”

The study, “Predictors of abdominal pain severity in patients with constipation-prevalent irritable bowel syndrome,” was published online in the Journal of Basic and Clinical Physiology and Pharmacology.