Older Patients Underrepresented in Atopic Dermatitis Trials

Megan Lam, BSc

Findings of a systematic review suggest older adults are underrepresented in randomized clinical trials of systemic treatment for atopic dermatitis.

The results emphasized the need for clinicians and patients to be aware of the evidence gap when prescribing systemic therapy for atopic dermatitis. Further, more randomized trials and observational studies that include an older population of patients with atopic dermatitis are needed.

Megan Lam, BSc, and investigators conducted a systemic review to examine the representation of older adults in randomized clinical trials of systemic immunomodulatory treatments for atopic dermatitis. The team also explored whether safety and efficacy data were reported specifically for older individuals.

Lam and the team searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and the ClinicalTrials.gov register from their inceptions to November 7, 2019. They analyzed randomized clinical trials investigating the use of currently used immunomodulatory medications for atopic dermatitis, including azathioprine, systemic corticosteroids, cyclosporine, dupilumab, methotrexate, and mycophenolate, against any comparator for adults at least 18 years old with the condition.

Study outcomes were whether inclusion and exclusion criteria included an upper age limit, the study included any patients at least 65 years old, and efficacy or safety outcomes reported separately for older patients. The investigators screened titles, abstracts, and full texts. During the process, study and participant characteristics, study design, and outcomes were extracted.

The team included 32 individual trials with a total of 4547 participants with a mean age of 34.4 years old. Overall, 11 trials reported upper age limits ranging from 42-70 years old. A majority of such trials examined outcomes of cyclosporine. The mean age of participants in trials with upper age limits was 30.2 years old, while the mean age in trials without such limits was 36.3 years old.

A majority of trials (69%) had criteria the investigators reported may be expected to disproportionately exclude older individuals from the trial cohort. Exclusion criteria often included the presence or history of malignant neoplasms (56%), uncontrolled hypertension (28%), renal or hepatic dysfunction (25%), and individuals taking drugs that could interfere with the pharmacokinetics of the intervention (22%).

There were 10 trials that included at least 1 participant aged at least 65 years old. The trials included 3124 participants with a mean age of 36.8 years old. In 7 of the trials, age was reported in categories and 4% of participants were at least 65 years old. Of the 112 participants, 3 were older than 84 years old. The trials were completed during or after 2010 and studied doses of dupilumab versus placebo.

None of the trials reported the number of older participants stratified by sex and none reported stratified efficacy or safety outcomes for older adult populations.

The study results suggested the current evidence base for systemic immunomodulatory treatment of atopic dermatitis might not be generalizable for older adults, which may be problematic due to the prevalence of the condition.

Lam and the team reported diagnostic criteria for atopic dermatitis could be a barrier preventing the enrollment of older adults in atopic dermatitis clinical trials. Because older adults are more likely to experience adverse effects of systemic medications, there is an increased need for evidence of the treatment safety for the older population.

Additional studies in older populations may help add to the safety and efficacy of such treatments for atopic dermatitis in older adults.

The study, “Inclusion of Older Adults in Randomized Clinical Trials for Systemic Medications for Atopic Dermatitis,” was published online in JAMA Dermatology.