Demographics, characteristics and medical treatment among adults with hand eczema in Denmark. A cross-sectional validation and registry-based study.

BACKGROUND: The international classification of diseases, 10th revision (ICD-10) includes several unvalidated diagnostic codes for hand eczema (HE). Knowledge is sparse on HE patient characteristics. OBJECTIVES: To validate selected HE ICD-10 codes in the Danish National Patient Registry (DNPR) and describe disease characteristics, lifestyle factors and medication use in adult HE patients. METHODS: Nineteen HE ICD-10 codes were selected and validated based on patient charts. Five cohorts were constructed based on the diagnostic code, DL30.8H (HE unspecified), in the DNPR: (i) patients with DL30.8H code (n = 8386), (ii) patients with DL30.8H code, but without atopic dermatitis (AD) (n = 7406), (iii) sex- and age-matched general population (n = 8386) without HE. Two additional cohorts nested in the DNPR included participants from the Danish Skin Cohort, (iv) patients with DL30.8H code but without AD (n = 1340) and (v) general population cohort (n = 9876). RESULTS: ICD-10 codes revealed positive predictive values ≥90% except irritant contact dermatitis (unspecified) (79.7%) and hyperkeratotic hand and foot eczema (84.1%). HE patients were most often women, middle-aged or older, of Danish ethnicity, had an atopic medical history and were smokers. Topical corticosteroid prescriptions were almost doubled in HE cohorts compared to general populations. CONCLUSION: We validated several HE ICD-10 codes and identified important HE patient characteristics.

Adult patients with alopecia areata report a significantly better medication adherence compared to those with atopic dermatitis: Results from a large cross-sectional cohort study.

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.