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.