High prevalence of concomitant anogenital lichen sclerosus and extragenital psoriasis in adult women.

OBJECTIVE

To analyze the prevalence of lichen sclerosus and psoriasis in gynecologic patients.

METHODS

The prevalence of lichen sclerosus and psoriasis individually, as well as the prevalence of both diseases in the same patient, was evaluated among 2,800 women attending a primary care gynecology practice for annual routine gynecologic examinations. The incidence of lichen sclerosus (new diagnosis of lichen sclerosus per year/population at risk) was calculated for the last 5 years.

RESULTS

Two hundred (7.1%) women had a biopsy-proven anogenital lichen sclerosus, and 57 women (2%) had an extragenital psoriasis vulgaris. Fifteen women had both diseases (0.5%). The prevalence of psoriasis in lichen sclerosus patients was 7.5% (15 of 200; 95% confidence interval 4.3-12.1%) compared with 1.6% (42 of 2,600) in the non-lichen sclerosus patient group. Lichen sclerosus was diagnosed in 13 of 15 psoriasis patients at an average of 19.5 years after the diagnosis of psoriasis at the age of 48 years (range 30-70 years). The incidence rates of lichen sclerosus for the last 5 years were 0.5% in 2002, 0.7% in 2003 and 2004, 1.9% in 2005, and 1.8% in 2006.

CONCLUSION

The prevalence of psoriasis in lichen sclerosus patients (7.5%) is higher than in the general population and among the non-lichen sclerosus patients in this practice (1.6%). This association may result from a similar immune dysregulation in these women.

LEVEL OF EVIDENCE: II.