As one of the most common skin diseases worldwide, atopic dermatitis (AD) affects up to 20% of the population in Western countries, according to Alexander Salava, MD, PhD. “In addition, AD often follows a chronic course and may severely impact patients’ QOL and functional capacities,” Dr. Salava says. “We have known for some time that AD is a heterogenous medical entity with a wide clinical spectrum. In this regard, there are relevant subtypes of AD, and we were interested in researching predictors of diseases severity. This information may help doctors anticipate the course and prognosis of the disease and, more importantly, focus on targeted management.”
For a study published in the Journal of the European Academy of Dermatology and Venereology, Dr. Salava and colleagues investigated clinical signs and patient characteristics associated with severe AD. “Since novel effective medical treatments for AD have been recently introduced and others are under development, we believed it would be relevant to search for factors predicting severity in patients’ medical history, clinical examination, or laboratory investigations,” Dr. Salava says. “These new medical treatments are also quite costly and merit a cost-benefit consideration. Therefore, severitypredicting characteristics are relevant.”
Total Patient Serum IgE Levels Were Measured
An observational, cross-sectional study was conducted, with a single clinical examination performed for 502 patients with AD in a tertiary healthcare hospital. In addition to disease severity, the researchers evaluated data on disease onset, smoking, AD in first-degree relatives, contact allergies, history of herpes infections, allergic sensitization, contact allergies, peanut and other food allergies, and atopic comorbidities, such as bronchial asthma.
Based on the clinical examination, they obtained information about patients’ BMI and the presence of hand dermatitis, palmar hyperlinearity, white dermographism, and keratosis pilaris. Dr. Salava and colleagues also measured total serum IgE levels, obtained the highest total IgE levels of the past 10 years, and investigated a panel of filaggrin and other genes of the epidermal barrier for loss-of-function mutations.
Key Determinants of AD Severity Observed
“Our principal findings indicated that possible determinants of AD severity were disease onset at less than age 2, male sex, smoking, and high BMI, concomitant asthma, palmar hyperlinearity, hand dermatitis, history of contact allergy, and elevated total IgE levels,” Dr. Salava notes. “We observed that these factors are relevant in other populations as well. Interestingly, allergic conjunctivitis, rhinitis, and atopic sensitization were not linked to AD severity.”
A positive association was found for hand dermatitis, contact allergies, and palmar hyperlinearity, Dr. Salava notes. White dermographism indicated a reverse association, showing to be a factor linked to a milder disease course and prognosis. In addition, it was observed that contact allergies might be secondarily caused by severe eczema (Table).
Major Challenges Exist in Treating Pediatric Patients With Severe AD
A proper evaluation of existing severity predicting factors in AD could shift the treatment strategy to a more effective one, considering the possible side effects and medical costs of treatment and its impact on the socioeconomic burden, Dr. Salava explains. “Additionally, a subtyping of patients to known severity determinants might help to locate patients with a milder disease course and better prognosis and thus warrant safer management strategies. For colleagues who treat AD, we would recommend keeping abreast of disease course-predicting clinical factors in different populations and treatment response predicting factors.”
In the future, “it will be interesting to see if there are factors that predict response to older and novel treatments and whether a profiling of patients might help in disease management,” Dr. Salava notes. “Furthermore, we still have major challenges in the treatment of severe AD in pediatric patients. There exists a high need to investigate the safety, tolerability, and practicability of AD medicaments in children and adolescents.