Rosacea, melanoma linked in white patients

Key takeaways:

• A strongly increased risk for malignant melanoma was found in patients with rosacea.
• Risks for other comorbidities were also found, including heart disease, ophthalmologic disease and joint problems.

Patients with rosacea have an increased risk for malignant melanoma, joint problems, metabolic disease and visual disturbances, according to a study.

“Rosacea particularly affects fair-skinned people of Celtic origin or northern European descent, with an estimated prevalence of 5% to 10% in these populations,” Jennifer von Stebut, of Charité-Universitätsmedizin Berlin, and colleagues wrote. “Though such a common disease, the pathophysiology underlying rosacea remains unclear.”

Researchers used the TriNetX platform and propensity score matching to create two real-world patient cohorts, matched by age and sex, of 122,444 patients with and without rosacea. Rosacea was determined using the ICD-10 code-based system.

They then conducted an analysis to determine the risk difference, risk ratio and odds ratio of different comorbidities.

Malignant melanoma and other skin neoplasm was the most strongly associated comorbidity with rosacea, with 12,128 of the 122,444 patients with rosacea also having concomitant skin cancer (OR = 6.031; 95% CI, 5.759-6.316).

A Kaplan-Meier analysis was then conducted finding risks for nonmelanoma skin cancer, as well as a “starkly increased risk” for malignant melanoma (RR = 5.533; 95% CI, 5.29-5.786), according to the authors.

Survival probability was 92.51% for those with rosacea and 97.71% for those without rosacea. Mortality was also higher in the patients with rosacea compared with those without rosacea (HR = 3.286; 95% CI, 3.101-3.481).

A subset of Asian patients was analyzed separately, which did not show the same association with melanoma. In two cohorts of 1,494 respective patients, the first with rosacea and the second without, each cohort had 10 patients with malignant melanoma.

An increased risk ratio for vascular disease (RR = 1.819; 95%CI, 1.793-1.844), heart disease (RR = 1.406; 95%CI, 1.39-1.423), ophthalmologic disease (RR = 3.785; 95% CI, 3.702-3.871), metabolic disease (RR = 2.175; 95% CI, 2.147-2.201), joint disease (RR = 2.854; 95% CI, 2.811-2.898) and type 2 diabetes (RR = 1.483; 95% CI, 1.458-1.509), were also found in the original study subsets.

Study limitations included the retrospective nature and sole use of ICD-10 code-based filtering, and the authors further recommended future studies consider confounding factors including skin type and past UV exposure.

“While rosacea has been previously linked to an increased risk of systemic diseases, our findings regarding malignant melanoma contrast with the findings of past studies,” the authors wrote. “These differences highlight the need for further investigation of the possible connection of these two dermatologic diseases.”