Genetic vs Environmental Factors That Correlate With Rosacea: A Cohort-Based Survey of Twins.

IMPORTANCE: To our knowledge, this is the first study on rosacea to formally define genetic and environmental contributions. OBJECTIVES: To study a cohort of identical and fraternal twins to determine whether genetic factors contribute to rosacea development and, if genetic factors are present, quantitatively estimate the genetic contribution, as well as to identify environmental factors that correlate with rosacea by controlling for genetic susceptibility. DESIGN, SETTING, AND PARTICIPANTS: Identical and fraternal twins were surveyed regarding risk factors implicated in rosacea. Faculty dermatologists determined a rosacea score for each twin participant according to the National Rosacea Society (NRS) grading system. Data were collected at the annual Twins Days Festival in Twinsburg, Ohio, on August 4-5, 2012, and August 2-3, 2013. Analysis was conducted for several months after each meeting. A cohort of 550 twin individuals, with most from Ohio, Pennsylvania, and the northeastern United States, participated. MAIN OUTCOMES AND MEASURES: The NRS score and rosacea subtype were assessed using the NRS grading system and physical examination by board-certified dermatologists. RESULTS: Among the 275 twin pairs (550 individuals), there were 233 identical twin pairs with a mean rosacea score of 2.46 and 42 fraternal twin pairs with a mean rosacea score of 0.75. We observed a higher association of NRS scores between identical vs fraternal twins (r = 0.69 vs r = 0.46; P = .04), demonstrating a genetic contribution. Using the ACE model (proportion of variance in a trait heritable secondary to additive genetics [A] vs the proportions due to a common environment [C] and unique environment [E]), we calculated this genetic contribution to be 46%. A higher NRS score was also significantly associated with the following factors: age (r = 0.38; P < .001) and lifetime UV radiation exposure (r = 0.26; P < .001). These associations remained after use of propensity score matching to adjust for multicollinearity. Other correlated variables included body mass index (r = 0.21; P < .001), smoking (r = 0.10; P < .02), alcohol consumption (r = 0.11; P = .01), cardiovascular comorbidity (r = 0.17; P < .001), and skin cancer comorbidity (r = 0.19; P < .001). CONCLUSIONS AND RELEVANCE: The study of twins allows us to separate genetic susceptibility and the influence of environmental factors affecting rosacea. We found that approximately half of the contribution to the NRS score could be accounted for by genetics and the other half by environment. We identified correlations between rosacea and UV radiation exposure, alcohol, smoking, skin cancer history, cardiac comorbidity, and age. These findings may help improve current management and expectations of individuals affected by rosacea.

The impact of vulvar lichen sclerosus on sexual dysfunction.

BACKGROUND: Lichen sclerosus (LS) is a chronic inflammatory condition that is known to arise on the vulva. Many women with LS report vulvar pain, often affecting a patient's quality of life. In this study, the sexual function of LS patients, with and without pain, was compared to control populations. MATERIALS AND METHODS: A case-control study to examine the relationship between LS and sexual dysfunction was conducted. A total of 335 women presenting to the gynecology clinic were included in the study: 197 women with biopsy confirmed LS were compared to two control groups (95 asymptomatic women were "healthy" controls and 43 women had vulvovaginal candidiasis) on self-reported current health complaints, medical and surgical history and current symptoms such as pain and itching, type and frequency of sexual activity, and satisfaction with sexual activity. RESULTS: Women with LS reported less frequent sexual activity than healthy controls (p=0.007) and Candida controls (p=0.04). Currently sexually active women with LS were significantly less likely to report vaginal intercourse (71.6%) than healthy controls (89.0%, p=0.003) or Candida controls (100%, p=0.0003), even though similar proportions of all three groups reported that vaginal intercourse was important. Satisfaction towards the quality of current sexual activity was significantly lower among women with LS compared with both the healthy and Candida control groups. 23.7% of women with LS reported that sexual activity was rarely or never satisfactory as compared with 0% of healthy controls (p<0.0001) and 6.5% of Candida controls (p=0.03). CONCLUSION: Women with LS have less frequent sexual activity and less satisfying sexual activity when compared with controls.