Epidemiology and socioeconomic impact of skin disease in lupus erythematosus.

The prevalence rates of systemic lupus erythematosus (SLE) may vary within 17-48/100,000 population worldwide. Although population-based epidemiological studies are still missing, the cutaneous variants of lupus erythematosus (LE) are 2-3 times more frequent than SLE itself. The most common age of onset is 20-40 y. Overall, cutaneous LE is regarded as a variant with less severe course and better prognosis. However, CDLE and SCLE last for many years and may lead, like SLE, to severe disability for work and limited life quality; also, a small proportion of patients with cutaneous LE develops SLE during the course of their disease. This implies considerable amount of medical management and costs for the community. Early recognition of cutaneous LE patients at risk to develop SLE and preventive measures against disease triggering factors are important tasks for physicians attending with cutaneous LE patients. It seems that signs of nephropathy, elevated ANA-titers and arthralgias may serve as prognostic predictors for transition into SLE. Characteristic features of cutaneous LE are photosensitivity and female predominance. UV light is a major environmental triggering factor in cutaneous LE. Skin lesions may be induced or preexistent lesions may exacerbate due to UV light in up to 80-90% of all patients. Therefore, socioeconomic counseling of the young patients, for example choice of occupation and sun protection, are essentials in compliant patients. Also, since females are 3-6 times more frequently affected than males, the possibility of hormonal influences including pregnancy and estrogen-containing drugs should be discussed. Risk considerations for females wishing to become pregnant are required, and avoidance of estrogen-containing contraceptives should be recommended.