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.

Assessment of hand eczema severity by patients using the hand eczema severity index (HECSI).

BACKGROUND: Hand eczema severity index (HECSI) is a widely used tool for assessment of hand eczema (HE) severity. Generally, HECSI has been used by health care providers, and a validation of the HECSI tool when used by patients is lacking. OBJECTIVES: To evaluate the construct validity and reliability of HECSI as a tool for patients based on comparison to HECSI assessments by physicians. METHODS: Patients with HE, enrolled from the dermatological outpatient clinic, Bispebjerg Hospital, assessed HE severity with a patient version of HECSI (patient-HECSI). Afterwards, HECSI was assessed by a trained physician (physician-HECSI). RESULTS: This study found a strong correlation and very good absolute agreement between patient-HECSI and physician-HECSI assessments with a correlation coefficient of 0.756 and intraclass correlation coefficient (ICC) of 0.844. Cronbach's alpha was 0.861 indicating very good internal consistency. CONCLUSION: With a strong construct validity and reliability, the patient-HECSI may be used by patients as a patient-reported outcome assessing their personal HE severity.