Study Links Rosacea to Melanoma

In a recent study that was published in Scientific Reports, scientists looked at the possibility of a connection between melanoma and rosacea, a widespread skin ailment that is typically primarily seen to be a cosmetic concern.

Context
For the study, they employed a sizable age- and sex-matched cohort (n = 244,888) made up of people of Caucasian, Black, Asian, Alaskan, and Pacific Islander ancestry.

Their results demonstrate that rosacea is substantially linked to an increased risk of visual impairments, metabolic diseases, joint issues, and type 2 diabetes (T2D), in contrast to earlier studies.

Interestingly, a significantly higher risk of melanoma was observed in the Caucasian sub-cohort, a finding that was not present in the Asian cohort. This ethnicity-related result could help to clarify inconsistent comorbidity findings from earlier research.

The current study supports the need for more investigation into the pathophysiology of this prevalent but little-understood condition, despite several significant limitations in its retrospective methodology.

What is rosacea, and why has it gone unnoticed by epidemiologists for such a long time?

Rosacea is a long-term skin disorder that mostly affects the cheeks, chin, nose, and forehead of those who have it, resulting in redness and rashes. Though it can affect anyone of any age or gender, the illness is most common in females between the ages of 30 and 50.

According to reports from around the world, those with fair complexion and those of Celtic heritage in northern Europe are thought to be more susceptible to the disease; their prevalence is estimated to be between 5 and 10%, while the global estimate is between 1 and 7%.

Alarmingly, not much is known about rosea, despite being mentioned in Geoffrey Chaucer’s “The Canterbury Tales” in the late 1300s and possibly by Theocritus as early as 200 BC.

Many factors have been suggested as causes of the illness, but none of them have ever been proven by science. These include exposure to ultraviolet light, smoking, alcohol, heat, exercise, psychological stress, and most often, heredity.

Since infections caused by Demodex species have been linked to rosacea symptoms in recent studies, oral antibiotics are the recommended therapeutic treatment when symptoms appear. Unfortunately, there is presently no permanent treatment for the illness; these measures only offer brief respite.

It’s conceivable that the long understudied nature of this widespread condition is due to the misconception that rosacea is only a cosmetic issue, which persisted until recently.

This widely held belief has been called into question by recent research, with an increasing amount of literature indicating that rosacea may be linked to autoimmune diseases, coronary artery disease, inflammatory bowel disease, and other chronic inflammatory problems.

Few research have looked at the connections between rosacea and cancer because dysregulated immunological and inflammatory responses are frequently identified as carcinogens, especially in skin tumors. Sadly, the results of these studies continue to be confusing and equivocal.

Malignant melanomas are the most aggressive and deadly types of skin cancer, accounting for almost 50% of skin cancer-related deaths annually but making up only 4% of all skin malignancies worldwide.

In order to lessen the financial burden of treating skin cancer, which is already the most frequent cancer subtype worldwide, it is critical to identify people at risk and risk factors as soon as possible.

Concerning the study

With the help of data from a large “real-world” database (the TriNetX platform), the current study attempted to investigate any possible links between rosacea and a number of systemic illnesses, including malignant carcinomas.

The collection comprised medical health records (diagnoses, prescriptions, test results, and genetic information) as well as demographic data (namely, age, sex, and ethnicity) from the 21,913,235 TriNetX patients who were registered between June and July 2023.

The International Statistical Classification of Diseases and Related Health Problems (ICD-10) code L71 (rosacea) was used to diagnose study participants, and a comparable number of age- and sex-matched non-rosacea patients were included as controls.

“A subset analysis was carried out on April 2nd, 2024 for rosacea patient with ICD-10 codes C43 [malignant melanoma of the skin] and C44 [other and unspecified malignant neoplasm of the skin] separately. 86% of the data is derived from US patients and ethnicity is routinely queried upon inclusion in the database.”

Using TriNetX analytics tools, statistical studies included propensity score matching, the Kaplan-Meier survival analysis (excluding melanomas), and comparative outcome analysis.

Furthermore, during an independent sub-cohort analysis, the observed comorbidities’ Risk Difference, Odds Ratios (ORs), and Risk Ratios (RRs) were computed.

Results and recommendations of the study

122,444 (69.2% female) of the 132,388 patients with ICD-10 code L71 (rosacea) had age- and sex-matched non-rosacea diagnoses that were included in the current analysis. 82% of them were Caucasian, 3% Black, 1.6% Asian, 10% unidentified, and the remainder were people from Alaska, India, Hawaii, or Pacific Islands.

“While the risk of being diagnosed with a vascular disease was at 0.185 in patients without rosacea, this risk increased to 0.336 in patients with rosacea [OR 2.234 (2.192, 2.276)].”

In contrast to earlier findings, rosacea was linked to statistically significant increases in the risks of metabolic disorders (OR = 3.165), ophthalmologic or joint diseases (OR = 4.164–4.801), heart disease (OR = 1.649), and type 2 diabetes (T2D; OR = 1.618).

Regretfully, skin neoplasms, particularly malignant melanomas (OR = 6.031), were the comorbidities most closely linked to rosacea.

In conclusion, this study is the first to definitively link rosacea to a wide range of comorbidities, some of which are potentially fatal, such as heart conditions and melanomas.

Though it has some notable limitations (using only retrospective data and ICD-10 codes), it does a great job of highlighting the significance of rosacea and the need for more research into this seemingly benign condition.

For more information: Rosacea is strongly associated with melanoma in Caucasians, Scientific Reports, https://doi.org/10.1038/s41598-024-62552-8