Seborrheic dermatitis and risk of incident peptic ulcer disease: A nationwide population‐based cohort study

Abstract Background Emerging evidence supports a strong association between the skin and the gut. The association between seborrheic dermatitis (SD) and peptic ulcer disease (PUD) was largely unknown. This study aimed to investigate the association of SD and PUD. Methods This nationwide population‐based cohort study was conducted using the Taiwan's National Health Insurance Research Database. A total of 19 445 participants was recruited. Each patient with a diagnosis of incident SD was matched to four patients without SD using propensity scores based on age, gender, index year, insurance amount, urbanisation level, Charlson comorbidity index (CCI), the presence of comorbidities and medication use. The primary endpoint was the development of incident PUD. Hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for PUD occurrence in relation to the presence of SD were calculated. Results Overall, patients with SD had a significantly higher risk for incident PUD than those without SD in both univariable (crude HR = 1.60, 95% CI 1.38–1.86, P < 0.001) and multivariable (adjusted HR = 1.58, 95% CI 1.36–1.83, P < 0.001) Cox proportional hazard regression models. Kaplan–Meier analysis indicated that the cumulative incidence of PUD was consistently higher in individuals with SD than those without SD (log‐rank test, P < 0.001). A higher risk of PUD was also found in individuals with SD than those without SD in all stratified analyses by age, gender, CCI and follow‐up time. Conclusion Patients with SD may have a higher risk for incident PUD. Further studies are warranted to validate our findings.