Related Experiment Video
Updated: Sep 7, 2025

Chronic Salmonella Infection Induced Intestinal Fibrosis
Published on: September 22, 2019
Occurrence of inflammatory bowel disease in patients with chronic inflammatory skin diseases: a cohort study:
Maria C Schneeweiss1,2,3, Julien Kirchgesner1, Richard Wyss1,2
1Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
Background:
Several studies have linked various chronic inflammatory skin diseases (CISDs) with inflammatory bowel disease (IBD) in a range of data sources with mixed conclusions.
Objectives:
We compared the incidence of IBD - ulcerative colitis (UC) and Crohn disease (CD) - in patients with a CISD vs. similar persons without a CISD.
Methods:
In this cohort study using nationwide, longitudinal, commercial insurance claims data from the USA, we identified adults and children who were seen by a dermatologist between 2004 and 2020, and diagnosed with either psoriasis, atopic dermatitis, alopecia areata, vitiligo or hidradenitis suppurativa. Comparator patients were identified through risk-set sampling; they were eligible if they were seen by a dermatologist at least twice and not diagnosed with a CISD. Patient follow-up lasted until either IBD diagnosis, death, disenrolment or end of data stream, whichever came first. IBD events, UC or CD, were identified via validated algorithms: hospitalization or diagnosis with endoscopic confirmation. Incidence rates were computed before and after adjustment via propensity-score decile stratification to account for IBD risk factors. Hazard ratios (HR) and 95% confidence intervals (CIs) were estimated to compare the incidence of IBD in CISD vs. non-CISD.
Results:
We identified patients with atopic dermatitis (n = 123 614), psoriasis (n = 83 049), alopecia areata (n = 18 135), vitiligo (n = 9003) or hidradenitis suppurativa (n = 6806), and comparator patients without a CISD (n = 2 376 120). During a median follow-up time of 718 days, and after applying propensity-score adjustment for IBD risk factors, we observed increased risk of both UC (HRUC 2·30, 95% CI 1·61-3·28) and CD (HRCD 2·70, 1·69-4·32) in patients with hidradenitis suppurativa, an increased risk of CD (HRCD 1·23, 1·03-1·46) but not UC (HRUC 1·01, 0·89-1·14) in psoriasis, and no increased risk of IBD in atopic dermatitis (HRUC 1·02, 0·92-1·12; HRCD 1·08, 0·94-1·23), alopecia areata (HRUC 1·18, 0·89-1·56; HRCD 1·26, 0·86-1·86) or vitiligo (HRUC 1·14, 0·77-1·68; HRCD 1·45, 0·87-2·41).
Conclusions:
IBD was increased in patients with hidradenitis suppurativa. CD alone was increased in patients with psoriasis. Neither UC nor CD was increased in patients with atopic dermatitis, alopecia areata or vitiligo. What is already known about this topic? Several studies have linked various chronic inflammatory skin diseases (CISDs) with inflammatory bowel disease (IBD) utilizing a range of data sources, with mixed conclusions. What does this study add? This large-scale, claims-based cohort study expands current knowledge by providing background rates for IBD across multiple CISDs using consistent methods and within a single, nationally representative patient population. We observed a relative increased risk of IBD in patients with hidradenitis suppurativa, but the overall incidence rate difference of IBD was generally low. Crohn disease alone was significantly increased in patients with psoriasis, and neither ulcerative colitis nor Crohn disease was increased in patients with atopic dermatitis, vitiligo or alopecia areata.
Related Concept Videos
Inflammatory Bowel Disease II: Crohn's Disease
Inflammatory bowel disease, commonly known as IBD, refers to a collection of disorders that lead to persistent inflammation of the gastrointestinal tract. The two types of IBD are ulcerative colitis, which impacts the colon, and Crohn's disease, which can involve any part of the gastrointestinal segment.
Crohn's disease
Crohn's disease is a chronic, systemic inflammatory bowel disease (IBD) that predominantly affects the gastrointestinal tract. It is marked by...
Chronic Bowel Disorders: Introduction
Irritable Bowel Syndrome (IBS) is a common disorder affecting the gastrointestinal tract. The distinctive feature is recurrent abdominal pain associated with altered bowel movements, manifesting as constipation, diarrhea, or fluctuating between both. The...
Inflammatory Bowel Disease I: Ulcerative Colitis
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
Inflammatory Bowel Disease III: Diagnostic Studies and Management I-Nutritional Therapy
Diagnostic studies
A colonoscopy is the definitive screening test, distinguishing ulcerative colitis from other colon diseases with similar symptoms. During a colonoscopy test, inflamed mucosa with exudate ulcerations can be observed, and biopsies are taken to determine the histologic characteristics of the...
Drugs for Treatment of Crohn's Disease in IBD Using Glucocorticoids
Skin Diseases and Disorders
Gram-positive Staphylococcus spp. and Streptococcus spp. are responsible for many of the most common skin infections. However, many...

