A recently published review article analyzed the epidemiology of atopic dermatitis and its increasing prevalence, and found that it may be more common in adults than previously thought.
In a recent review article published in the journal Dermatology Clinics, Jonathan I. Silverberg, MD, PhD, MPH, from Northwestern University Feinberg School of Medicine, Chicago, Illinois, highlights the increasing burden of atopic dermatitis.
“Atopic dermatitis is associated with a considerable public health burden owing to its very high prevalence, considerable patient-burden, and increased healthcare utilization,” writes Dr. Silverberg.
Atopic dermatitis is a chronic inflammatory skin disease, and advances in understanding of its epidemiology have continued to emerge in recent decades. The prevalence of this disease has also recently increased.
Studies estimate the prevalence of childhood atopic dermatitis to range from 6% to 12.98% in the United States. Worldwide, the reported prevalence varies markedly, however, it ranges from 0.9% in India to 22.5% in Ecuador in children aged 6 years to 7 years, and from 0.2% in China to 24.6% in Colombia in those aged 13 years to 14 years. Data also suggest that the prevalence of the disease in children is higher in African Americans/blacks than in Caucasians. Interestingly, studies also suggest that atopic dermatitis is more common in wealthier, developed nations than in poorer, developing ones.
Although traditionally considered a disease of childhood, studies have increasingly suggested that atopic dermatitis may be more common in adults than previously thought. Studies conducted in the United States in 2010 and 2012 reported 1-year prevalence rates of the disease in adults as 10.2% and 7.2%, respectively. International studies estimated prevalence rates ranging from 2% to 6.9% before 2000. And, although a controversial topic, adult-onset of atopic dermatitis may also be more common than previously suspected. In a US study of 60,000 households, 54% of respondents reported disease onset in adulthood. In addition, in a Turkish study of 376 patients with atopic dermatitis, 16.8% reported adult-onset disease.
Data from 2007—2008 showed that 67% of US children reportedly had mild disease, 26% had moderate disease, and 7% had severe disease. An estimated 2.98 million children, therefore, have moderate to severe disease, with significant variation among states. Although studies have shown a decreasing prevalence of atopic dermatitis with advancing age, the relative proportions of moderate and severe disease appear to increase with age. African Americans/blacks may also be prone to more severe disease and increased healthcare utilization for the disease than whites.
Although data about the prevalence of and risk factors for moderate to severe atopic dermatitis in adults are lacking, a 2013 survey of patients with the disease showed that 50% of respondents reported having moderate to severe disease. “More population-based studies are needed to determine the prevalence and risk factors of moderate-severe [atopic dermatitis] in adults from the United States and internationally, writes Dr. Silverberg.
Although atopic dermatitis is typically nonfatal, Dr. Silverberg emphasizes its substantial associated disease-related morbidity and disability. “The 2010 Global Burden of Disease survey found that [atopic dermatitis] had the highest disability-adjusted life-years among skin disorders, which reflects both the high prevalence and patient burden.”
Recent estimates of the costs of atopic dermatitis in the United States are lacking, but older studies estimated its annual direct payer costs to be $364 million in 1993, and $3.8 billion in 2002. However, Dr. Silverberg believes the actual costs of atopic dermatitis are probably significantly higher now, in particular because of worldwide population growth, increasing prevalence of the disease, and additional costs such as indirect costs and costs associated with comorbidities. Two recent US studies of adults with atopic dermatitis showed that excess out-of-pocket costs related to healthcare utilization ranged from $371 to $489 per person-year.
According to Dr. Silverberg, atopic dermatitis places a large burden on the patient. In addition to the direct effects of the physical signs and symptoms of disease (such as pruritus and pain), atopic dermatitis can also have indirect effects on the patient. These include negative effects on sleep quality, on physical activity, and on activities of daily living.
Studies have also shown that children and adults with atopic dermatitis have significantly higher rates of multiple medical and mental health comorbidities. These include asthma, food allergy, depression, anxiety, attention-deficit/hyperactivity disorder, fractures, and cardiovascular disease.
“Future research is needed to identify population-based risk factors and opportunities for disease prevention,” Dr. Silverberg concludes.