Psoriasis is significantly associated with inflammatory bowel disease (IBD), according to a study recently published in JAMA Dermatology.
To investigate the association between psoriasis and IBD, researchers conducted a systematic review and meta-analysis using studies from MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials between inception and January 17, 2018. Investigators included studies that were case-control, cross-sectional, or cohort studies and examined either the odds or risk of IBD in patients with psoriasis. The studies were neither limited geographically nor linguistically. Analyses for Crohn disease and ulcerative colitis were performed separately, and a subgroup analysis on psoriatic arthritis was conducted.
Five case-control or cross-sectional studies and 4 cohort studies with a total of 7,794,087 participants were included. Investigators discovered a significant association between psoriasis and Crohn disease (odds ratio [OR]=1.70, 95% CI, 1.20-2.40) and between psoriasis and ulcerative colitis (OR= 1.75, 95% CI, 1.49-2.05).
Additionally, investigators found an increased risk for Crohn disease and ulcerative colitis in patients with psoriasis (risk ratio=2.53; 95% CI, 1.65-3.89 and risk ratio=1.71; 95% CI, 1.55-1.89, respectively).
Only one cohort study analyzed the relationship between severity of psoriasis and IBD. Due to the variation in sample size across the studies included, the weight of the different studies varied in subgroup analyses. Despite this limitation, the direction of effects was consistent across the analyzed studies.
The results of this meta-analysis indicate that patients with psoriasis are prone to comorbid Crohn disease and ulcerative colitis. Gastroenterology consultation may be advisable for patients with psoriasis who present with bowel symptoms.
Fu Y, Lee CH, Chi CC. Association of psoriasis with inflammatory bowel disease: a systematic review and meta-analysis [published online October 24, 2018]. JAMA Dermatol. doi: 10.1001/jamadermatol.2018.3631