Background
Alopecia areata (AA) and atopic dermatitis (AD) are chronic skin diseases where the suboptimal medication adherence (MA) may result in poor clinical outcomes.

Objective
To assess the impact of AA on MA among adults compared to AD.

Methods
Patient reported MA of adults with AA were compared with AD. Patients were identified from the Danish Skin Cohort, a nationwide prospective cohort of dermatological patients in Denmark. We used the Medication Adherence Report Scale- 5, a self-reporting questionnaire, to assess MA. Demographic and disease characteristics were collected. Logistic regression was conducted.

Results
Patients with AA reported higher MA than AD (mean 21.81 vs 18.29). Logistic regression analyses showed AA diagnosis had a statistically significant positive effect on MA (odds ratio = 3.94, 95% CI 2.01-8.89). Men reported significantly higher MA (odds ratio = 1.49, 95% CI 1.14-1.94). Current disease severity did not impact MA.

Limitations
Data were self-reported by patients. Data regarding the specific treatment undergone by patients were not available.

Conclusion
Patients with AA have significantly higher MA compared to patients with AD. The stability of AA patients’ symptoms may lead to higher MA due to a desire for disease control. Conversely, the sporadicity of AD symptoms could negatively affect adherence, causing fluctuations in medication use.