Atopic Dermatitis in Adulthood Linked to Increased Risk for VTE

While adults with atopic dermatitis (AD) appear to be at increased risk for incident venous thromboembolism (VTE), the absolute risk difference is small for adults with vs without AD, according to study results published in JAMA Dermatology.

Researchers sought to evaluate patients with AD in Taiwan for risk of incident VTE (deep vein thrombosis [DVT] and/or pulmonary embolism [PE]).

The researchers conducted a population-based, nationwide, retrospective, cohort study using the National Health Insurance Research Database ICD-9 and ICD-10 codes to find adults at least 20 years of age with newly diagnosed AD between 2003 and 2017 and matched (by sex and age) controls. The overall analysis included 142,429 patients in the AD cohort (mean age [SD], 44.9±18.3 years; 54.9% women) and 142,429 patients in the non-AD cohort (mean age [SD], 44.1±18.1 years; 55.9% women).  

Hazard ratios (HRs) for VTE were estimated using a Cox regression model. Sensitivity analysis and analyses stratified by sex and age were performed. Patients with records of VTE before the index date were excluded from both cohorts. The patients were followed through December 2018, death, or the occurrence of VTE (AD cohort mean follow-up, 7.15±4.4 years; non-AD cohort mean follow-up, 7.09±4.4 years). Hypertension was the most common comorbidity (17.1% AD cohort; 16.0% non-AD cohort).

A total of 1066 patients (0.75%) in the AD cohort developed VTE during follow-up (incident rate over 1000 person-years [IR], 1.05) compared with 829 patients (0.58%) in the non-AD cohort (IR, 0.82). The researchers noted a significantly increased risk for incident VTE among adults with vs without AD (HR, 1.28; 95% CI, 1.17-1.40).

An association between AD and higher risks for PE (HR, 1.30; 95% CI, 1.08-1.57; IR, 0.25) and DVT (HR, 1.26; 95% CI, 1.14-1.40; IR, 0.85) was suggested by individual analysis.

In subgroup analysis, the researchers noted an increased risk for incident VTE compared with controls by severity (mild AD HR, 1.30 and 95% CI, 1.12-1.51; severe AD HR, 1.35; 95% CI, 1.19-1.53), with no significant difference in terms of VTE risk between mild vs severe AD (HR, 1.04; 95% CI, 0.92-1.18). Similar results were reported for risks of DVT and PE.

Stratification by age showed no significance for increased risk for incident VTE associated with AD for patients younger than 45 years of age (HR, 1.03; 95% CI, 0.83-1.27), but there was a significant association for patients at least 45 years of age (HR, 1.25; 95% CI, 1.13-1.38). Stratification by sex showed a significant association for both sexes between AD and increased risk for VTE (women HR, 1.26; 95% CI, 1.11-1.43; men HR, 1.39; 95% CI, 1.22-1.59). Similar results were reported for risks for DVT and PE.

The risk for VTE remained significantly increased in patients with AD (HR, 1.45; 95% CI, 1.04-2.03) in the sensitivity analysis excluding users of systemic steroids.

Study limitations include possible unmeasured confounding, possible misclassification in ICD codes, exclusion of patients with persistent AD, and exclusion of 18- and 19-year-old patients (civil law in Taiwan defines adults as persons aged 20 years and older but many patients with AD are diagnosed at a relatively young age).

“The results of this cohort study suggest that [atopic dermatitis] in adulthood is associated with an increased risk of VTE; however, the absolute risk difference of VTE between adults with and without AD appears small,” the researchers concluded. They noted a 1.28-fold hazard for VTE among adults with AD compared with adults without AD. The researchers added, “Prompt prophylaxis with anticoagulants may be imperative in patients with symptoms that suggest VTE. This study’s findings may also have implications for interpreting pharmacovigilance studies on [Janus kinase] inhibitors.”

This article originally appeared on Dermatology Advisor