A Cup of Prevention?
Rosacea is a common inflammatory skin disease that is estimated to affect about 5.46% of the adult population worldwide.1 Despite the prevalence of this disease, many questions, including those regarding its development, risk factors, and prevention, remain unanswered.
Recently, Suyun Li, PhD, with the department of epidemiology and health statistics in the School of Public Health at Qingdao University in Qingdao, Shandong, China, led the first large cohort study that assessed the potential connection between caffeine intake and the risk of developing rosacea.2 “Caffeine is known to decrease vasodilation and have immunosuppressant effects. However, the heat from coffee may be a trigger for rosacea flares,” the researchers wrote.2 To better elucidate this relationship, they analyzed data from the Nurses’ Health Study II.
A total of 82,737 women who reported on their intake of coffee, tea, soda, and chocolate consumption were included in the final analysis. The researchers found an inverse association between caffeine intake and rosacea risk after adjusting for other risk factors (hazard ratio [HR] for highest quintile vs lowest quintile of caffeine intake, 0.76; 95% CI, 0.69-0.84), with a significant inverse association found between caffeinated coffee intake and rosacea risk (HR for 4 or more servings per day vs less than 1 per month, 0.77; 95% CI, 0.69-0.87).2 More information about the study can be found in the November issue of The Dermatologist3 or online.
Dr Li and coauthor Wen-Qing Li, PhD (no relation), assistant professor of dermatology at the department of epidemiology at Brown University in Providence, Rhode Island, discussed their findings and the implications for clinical practice and future research.
Q. Your study showed an inverse association between coffee intake and the risk for developing rosacea. Could you further elaborate on the significance of this finding and how it may affect the management and understanding of rosacea?
A. Our finding that consuming caffeinated coffee protects against the risk of developing rosacea may have clinical and public health implications. General public messages are warranted regarding the potential favorable effect of caffeine intake and coffee consumption on preventing rosacea.
Although the focus of this study was on the risk of developing rosacea, our findings, at least, do not support limiting caffeine intake and coffee consumption as a means to prevent rosacea flares. Physicians should be aware of these associations in order to address patients’ queries.
Q. Why did you and your team decide to focus on caffeine/coffee?
A. We focused on caffeine/coffee intake because previous studies on this topic reported differing effects of caffeine/coffee on rosacea and had inconsistent findings. In addition, these studies were limited by the study design and underpowered sample size.
It is also worth noting that our study examined whether caffeine and coffee intake could change the risk of developing rosacea, whereas other previous studies only focused on the effect among patients already diagnosed with rosacea. To clarify the association between caffeine intake, coffee consumption, and the risk of developing rosacea, we conducted the systematic analysis based on a well-established large cohort of women.
Q. Do you have any theories on why caffeine/coffee is beneficial?
A. Although the exact mechanisms underlying the observed findings would require lab bench work to clarify, we propose several possible mechanisms. One possibility is caffeine’s effect on vascular contractility. Also, caffeine might contain antioxidant agents and have immunosuppressant effects, which may result in decreased inflammation in rosacea. Moreover, caffeine may modulate hormone levels, including levels of adrenaline, noradrenaline, and cortisol, which may affect the development of rosacea.
In addition, we hypothesize that the lack of association with rosacea found for caffeinated food and drinks other than coffee is due to the low absolute intake of caffeine from those sources.
Q. Were there any findings that surprised you and your team?
A. The protective effect of caffeine against rosacea risk was expected based on our hypothesis. However, we were still surprised to observe such a robustly inverse association between caffeine intake, caffeinated coffee consumption, and the risk of developing rosacea. We were thrilled to yield such findings in our study.
Q. What are the implications of your study in regard to using diet to manage rosacea symptoms?
A. Patients with rosacea should not be discouraged from drinking coffee due to the fact that our findings do not support limiting caffeine intake and coffee consumption as a means to prevent flares.
1. Gether L, Overgaard LK, Egeberg A, Thyssen JP. Incidence and prevalence of rosacea: a systematic review and meta-analysis. Br J Dermatol. 2018;179(2):282-289.
2. Li S, Chen ML, Drucker AM, et al. Association of caffeine intake and caffeinated coffee consumption with risk of incident rosacea in women [published online October 17, 2018]. JAMA Dermatol. doi:10.1001/jamadermatol.2018.3301