Risk of herpesvirus, serious and opportunistic infections in atopic dermatitis: a population-based cohort study

Background Staphylococcal and herpes simplex virus (HSV) infections are commonly recognized in atopic dermatitis (AD), but less is known about other types of infections. Objectives To determine the risk of herpesvirus infections, serious infections and opportunistic infections in patients with AD. Methods We conducted a population-based cohort study using UK-based electronic medical records data. Patients with AD were each matched to up to five unaffected patients on age, practice and index date. AD severity was defined using treatments as a proxy. Outcomes were incident herpesvirus infections [cytomegalovirus (CMV), Epstein-Barr virus (EBV), HSV or varicella zoster virus (VZV)], serious infections and opportunistic infections. Results Among 409 431 children and 625 083 adults with AD matched to 1 809 029 children and 2 678 888 adults without AD, respectively, adjusted Cox regression models showed children and adults with AD had a 50-52% greater risk of HSV and 18-33% greater risk of VZV, with risk increasing in parallel with AD severity. CMV risk was elevated among children with AD [hazard ratio (HR) 2 center dot 50, 95% confidence interval (95% CI) 1 center dot 38-4 center dot 54] and adults with severe AD (HR 4 center dot 45, 95% CI 1 center dot 76-11 center dot 25). Patients with AD had a 26-40% increase in risk of serious infections, with severe AD carrying the greatest risk. Although rare, opportunistic infections were associated with all severities of AD in adults (overall HR 1 center dot 31, 95% CI 1 center dot 20-1 center dot 42), but were not associated with AD in children. All estimates remained consistent after excluding patients receiving immunosuppressive treatments for AD. Conclusions AD is significantly associated with herpesvirus infections, serious infections and opportunistic infections in a 'dose-dependent' manner with increasing severity. AD may increase susceptibility to infections exclusive of immunosuppressive medications.

Automated summary

Atopic dermatitis is significantly associated with herpesvirus infections, serious infections, and opportunistic infections, with the risk increasing with the severity of AD.