Which statement best describes the relationship between cigarette smoking and the two major forms of idiopathic inflammatory bowel disease?

• A Smoking increases relapse risk in both Crohn disease and ulcerative colitis
• B Smoking has no measurable influence on either disease once diagnosis is established
• C Smoking protects against Crohn disease but worsens the course of ulcerative colitis
• D Smoking worsens the course of Crohn disease but appears protective against ulcerative colitis ✓

Explanation

Active smoking roughly doubles the risk of relapse and surgery in Crohn disease, so cessation is a core part of its management. In contrast, ulcerative colitis is less common among smokers, tends to present after smoking cessation, and nicotine has shown some therapeutic benefit in trials. This inverse relationship between the two diseases is a repeatedly examined teaching point and also explains why former smokers carry an increased incidence of new-onset ulcerative colitis.

Reference: Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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