Rosacea related to sunburn, not alcohol use

Internal Medicine News, May 15, 2009 by Robert Finn

SAN FRANCISCO -- Alcohol has little to do with the development of the facial redness, swelling, and vascular abnormalities characteristic of rosacea, despite conventional wisdom, study results have shown.

In a case-control study comparing 65 patients with rosacea with 65 control subjects, Dr. Alexa Boer Kimball of Harvard Medical School, Boston, found no relationship between rosacea and current or former alcohol consumption. On the other hand, people with rosacea were three times more likely than controls to have a family member who also had the condition. And people with rosacea were eight times more likely to have a history of blistering sunburn, she reported at the annual meeting of the American Academy of Dermatology.

Specifically, 34% of the patients with rosacea had an affected family member, compared with 10% of the controls. And 44% of the patients with rosacea reported having had a blistering sunburn at some point in their lives, compared with 5% of the controls. Both differences were statistically significant.

In an earlier retrospective study involving digital photographs of 2,933 women from around the world, Dr. Kimball and her colleagues found that women with rosacea had a significantly higher mean body mass index than controls (27.6 kg/m2 vs. 24.3 kg/m2). In the current case-control study, the investigators found no significant difference in mean BMI between rosacea patients and controls (26.6 vs. 26.1).

The case-control study also failed to find significant differences between the groups in blood pressure, the use of sunscreen, smoking history in pack-years, heart disease, hypertension, or depression.

However, Dr. Kimball's study did confirm the stereotype of the rosy-cheeked Brit associated with comedian W.C. Fields, who had rosacea. The rate approached 25% among white women from London, significantly higher than the rate among white women from other parts of the world, even after controlling for Fitzpatrick skin type.

"There may be both genetic and environmental influences that are independent and beyond just [patients'] ability to manage sun radiation that might be important," Dr. Kimball said during a press briefing. "We're very much at the beginning of understanding the prevalence of disease, what the risk factors might be, and whether there are ways to avoid the development of rosacea over time."

Dr. Kimball's study also found no difference between patients and controls in rates of hypertension. "That was an important hypothesis,'' she said in an interview, "since we do think that rosacea is related to some pathology in the vasculature system."

But she said her study results were not as definitive regarding two other factors: "one, body mass index and how weight may be playing a role in the development of rosacea. The second finding that bears further analysis--because the findings are somewhat contradictory--has to do with smoking." Smoking can cause premature aging of the face and also can damage small blood vessels. Dr. Kimball said her study had several important take-home messages for physicians and patients. Physicians need to know that rosacea is very common in some populations, that the condition has strong negative effects on quality of life, and that it remains undertreated.

Patients also need to know that "we don't know yet how to prevent it well. But it would seem prudent in people with a family history of rosacea that is strong to take basic preventative measures, which include sun protection," she said.

Dr. Kimball stated that she had no conflicts of interest related to her study.