Characteristics of chromium-allergic dermatitis patients prior to regulatory intervention for chromium in leather: a questionnaire study.

BACKGROUND

Chromium-tanned leather articles currently constitute the most important cause of contact allergy to chromium in Denmark. A regulation on the content of hexavalent chromium in leather was adopted in November 2013 by the EU member states.

OBJECTIVES

To characterize patients with chromium allergy and their disease, to serve as a baseline for future studies on the potential effect of the new regulation on chromium in leather.

METHODS

A questionnaire case-control study was performed on 155 dermatitis patients with positive patch test reactions to potassium dichromate and a matched control group of 621 dermatitis patients. Comparisons were made by use of a χ(2) -test and the Mann-Whitney U-test. Logistic regression analyses were used to test for associations.

RESULTS

Sixty-six per cent of chromium-allergic patients had a positive history of contact dermatitis caused by leather exposure. They had a significantly lower quality of life (p < 0.001), a higher prevalence of dermatitis during the last year (p = 0.008), a higher use of medication during the past 12 months (p = 0.001) and a higher prevalence of sick leave (p = 0.007) than patients in the control group.

CONCLUSIONS

Chromium-allergic patients have more severe and more chronic contact dermatitis. Their primary chromium exposure comes from leather articles.