UV Radiation and Exposome: Key Factors in Pathophysiology of Rosacea

Portrait of a young pretty Caucasian woman who frowns and shows reddened and inflamed cheeks. Beige background. Copy space. The concept of rosacea, healthcare and couperose.
The etiology of rosacea, with an emphasis on the role of UV radiation and exposome, and to review the importance of nonpharmacologic strategies focusing on photoprotection, is described.

Ultraviolet (UV) radiation and the exposome have key roles in the development of rosacea, and water-based sunscreens are recommended in patients with the disorder, according to study findings published in the Journal of Cosmetic Dermatology.

Investigators conducted a literature search on PubMed from January 1990 to November 2020 about the etiology of rosacea, including the role of UV radiation and the exposome, and nonpharmacologic therapies that focus on photoprotection.1

Rosacea may be caused by the dysregulation of innate and adaptive immune systems and/or neurovascular dysfunction, a disrupted skin barrier, and a genetic predisposition. The exposome may be a leading factor in inducing this impaired immune or neurovascular response, according to the researchers.

Lifetime UV radiation exposure is significantly associated with rosacea and is the most important overall environmental variable, noted the study authors. UV radiation is involved in all key aspects of the disorder, including skin inflammation, neoangiogenesis, telangiectasia, and fibrosis.

Air pollution, smoking, nutrition, stress, and heat can all trigger or exacerbate rosacea. The use of soap-free gentle facial cleansers and cosmetically pleasing moisturizers without fragrance are recommended, according to the investigators.

Sun protection is key to effective management of the disorder. “Daily use of a very high-tolerance broad spectrum sunscreen with a minimum sun protection factor (SPF) of 30 is necessary,” stated the researchers.

Determining the best sunscreen for patients with rosacea can be challenging, however, as studies are lacking. The researchers cited a published report tested a novel water-based sunscreen SPF 50+ containing 5 UV filters, 2 emollients, and 3 skin conditioners that found that patients had significantly less erythema, dryness, and scaling after 21 days. Another study found that a tinted daily SPF-30 facial moisturizer improved skin appearance and dryness, reduced transepidermal water loss, and increased electrical capacitance was also mentioned.

“Products with broadband UV protection, water-based, easy to remove, containing ingredients with emollient, anti-inflammatory, antioxidant, and vasoregulatory properties should be preferred,” advised the study authors. “The use of tinted sunscreens or those containing green pigment for camouflage could be considered and discussed with the patient.”

Disclosures: ISDIN financed the publication expenses for this study, and 3 of the authors reported affiliations with ISDIN. Please see the original reference for a full list of disclosures.


Morgado-Carrasco D, Granger C, Trullas C, Piquero-Casals J. Impact of ultraviolet radiation and exposome on rosacea: key role of photoprotection in optimizing treatment. J Cosmet Dermatol. Published online February 24, 2021. doi:10.1111/jocd.14020