Smoking worsens relapse risk in Crohn's patients, study confirms

Last Updated: 2016-03-09

By Reuters Staff

NEW YORK (Reuters Health) - Crohn's disease (CD) patients who smoke are at increased risk of disease relapse, regardless of whether or not they are taking anti-TNF drugs or immunosuppressants, new research suggests.

"This prospective multicenter study confirms that tobacco smoking still impacts the clinical course of CD in the biologic era," Dr. Miquel Sans of Centro Medico Teknon in Barcelona and colleagues state. "Even in the present era of widespread use of drugs that might change the natural course of the disease, achieving a complete smoking cessation should remain one major therapeutic goal in the management of smokers with CD."

Tobacco smoking is the only known environmental risk factor associated with CD, Dr. Sans and his team note in their report, online February 9 in the American Journal of Gastroenterology.

"Although the notion that tobacco smoking worsens the clinical course of CD is commonly accepted, a careful review of the literature does not entirely support this concept," they add.

Also, the researchers point out, most research on smoking and CD relapse risk was done in the 1990s, before the introduction of anti-TNF drugs and more aggressive immunosuppressant treatment.

To investigate the relationship between smoking and CD relapse in more recent years, the researchers looked at 573 CD patients in clinical remission, including 148 continuing smokers, 190 nonsmokers, 160 former smokers, and 75 quitters. Follow-up lasted four years.

Continuing smokers were at significantly higher risk of relapsing than nonsmokers, with an incidence rate ratio of 1.53. However, relapse incidence was similar for former smokers, quitters and nonsmokers.

Multivariate analysis showed smoking independently predicted relapse (hazard ratio, 1.58). Time-dependent analysis showed that smokers relapsed earlier, and that being on anti-TNF drugs or immunosuppressants did not affect their time to relapse.

"In addition to the potential clinical benefits associated with quitting smoking, it has recently been shown that funding smoking cessation programs for CD patients might be extremely cost-effective," Dr. Sans and his team write. "Further studies comparing success rates and costs of different smoking cessation strategies specifically targeted at CD patients are urgently needed."

Dr. Sans was not available for an interview by press time.

SOURCE: bit.ly/24QgWdP

Am J Gastroenterol 2016.