Older Adults Are Often Excluded From RCTs of Systemic Treatments for Atopic Dermatitis

Although atopic dermatitis is common in adults 65 years and older, they are underrepresented in randomized controlled trials (RCTs) of systemic treatments for the condition. Given that older adults have a higher risk for adverse events, there is a need for more trials and studies that include this population, according to the findings published in JAMA Dermatology.

While atopic dermatitis frequently begins in childhood, research has shown that it is prevalent in adulthood and a second peak in incidence occurs after 60 years.

“Despite increased recognition that atopic dermatitis can persist, recur, or begin later in life, it is unclear whether the evidence base for the safe and effective treatment of atopic dermatitis applies to that population,” the authors explained. They added that the systemic treatments that the American Academy of Dermatology recommends in atopic dermatitis guidelines “can all cause serious adverse events, especially in patients with diminished renal function and other physiologic changes associated with aging.”

They analyzed RCTs that studied the use of azathioprine, systemic corticosteroids, cyclosporine, dupilumab, methotrexate, and mycophenolate in atopic dermatitis. The outcomes of interest were:

• Inclusion and exclusion criteria that included an upper age limit
• Participants in the study 65 years and older
• Efficacy
• Safety outcomes that were reported separately for older patients

The study included 45 records of 32 individual trials comprising a total of 4547 participants. The mean age of participants across the trials was 34.4 years.

One-third of the trials had upper age limits that ranged from 42 to 70 years. Meanwhile, 22 trials (69%) had “eligibility criteria that might be expected to disproportionately exclude older individuals from the trial cohort.” For instance, 18 trials excluded participants who had a presence of history of malignant neoplasms, 9 excluded people with uncontrolled hypertension, 8 excluded individuals with renal or hepatic dysfunction, and 7 excluded individuals taking drugs that could interfere with the intervention.

Only 10 trials reported at least 1 participant aged 65 years or older. While 3 of the trials did not report the proportion of older individuals, 7 trials did include participant age in categories with 112 out of a total of 2693 participants (4%) being 65 years or older. The 7 trials that included age categories studied dupilumab vs placebo.

The authors noted that none of the trials reported efficacy or safety outcomes by age.

The findings suggest that current evidence from trials may not be generalizable to older adults.

“Observational studies in older populations would help to clarify the safety and efficacy of systemic treatments for atopic dermatitis, and future trials should endeavor to increase participation of older adults,” the authors concluded.

Reference

Lam M, Zhu JW, Maqbool T, et al. Inclusion of older adults in randomized clinical trials for systemic medications for atopic dermatitis: a systematic review. JAMA Dermatol. 2020;156(11):1240-1245. doi:10.1001/jamadermatol.2020.2940