Passive Smoking and Worsening Crohn’s Disease

S Scharrer et al. Inflamm Bowel Dis 2021; 27: 379-385. Passive Smoking Increases the Risk for Intestinal Surgeries in Patients With Crohn’s Disease

This was a retrospective cohort study which included 169 patients who never smoked actively, 91 patients (54%) were exposed to passive smoking.

Key finding:

  • Exposed patients were more likely to undergo intestinal surgery than nonexposed patients (67% vs 30%; P < 0.001). Multivariate Cox regression analysis revealed that passive smoking was an independent risk factor for intestinal surgeries (hazard ratio, 1.7; 95% CI, 1.04–2.9; P = 0.034)

The associated editorial (RA John, RB Geary, pgs 386-387, Full Text: Smoking Cessation for Patients With Crohn Disease: Not Just for the Patient?) makes several useful points:

  • Smoking has long been identified as one of the strongest environmental risk factors for both the development of Crohn disease (CD) and the worsening of the disease course.
  • Studies in smokers with CD have reported that the risk of flares and complications matches that of nonsmokers with CD after 1 year of abstinence.
  • It would be reasonable to expect that a similar risk reduction exists for patients who can become passive-smoke-free. In addition, their likelihood of remaining smoke-free themselves is increased if they live in a smoke-free household.

My take (from editorial): “Clinicians should consider widening the scope of smoking cessation counseling to include not just patients but also their cohabitants.”