Short summary

The aim of this study is to do a national register study on the association between cutaneous lupus erythematosus (CLE) and the development of systemic lupus erythematosus (SLE).

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Rationale

Cutaneous lupus erythematosus, lupus of the skin, is a chronic skin disease where the patients often are particularly predisposed to the disease. The disease might occur separately or be a manifestation of the connective tissue disease, Systemic lupus erythematosus, on the skin. The incidence (number of new patients) of CLE in Denmark is not known, but two foreign studies have shown the incidence in both Sweden and the United States to be 4/100.000, the majority being women (gender ratio 3:1).

There are only very few studies which provide a risk estimate of CLE patients' risk of developing SLE. A Swedish national registry study showed that 20% of the newly diagnosed patients with CLE got a SLE diagnosis within 3 years. A small American registry study showed that 5% of newly diagnosed patients with CLE where diagnosed with SLE within 5 years and 23% had an SLE diagnosis after 25 years.

Aim:

To do a national register study with data from 1995 to 2014 for patients diagnosed with CLE. 

We wish to examine:

• Median time between CLE diagnosis and SLE diagnosis and vice versa
• How many develops SLE distributed on subtypes of CLE
• The incidence of CLE
• Development of CLE and SLE over time

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Description of the cohort

Data will be collected from patients diagnosed with CLE and SLE from 1995-2014.

Data and biological material

Data regarding diagnoses, time of debut and possibly date of death will be collected from the National Patient Register, the Danish Pathology Register and social security number.

Collaborating researchers and departments

Department of Dermatology and Allergy Centre, Odense University Hospital

• Professor Anette Bygum

Department of Reumatology, Odense University Hospital

• Consultant Anne Voss, PhD

OPEN Odense Patient data Explorative Network, Odense University Hospital

• Postdoc Mette Bliddal, PhD
• Statistician Sören Möller, PhD