Although sun exposure may be the most common rosacea trigger, patients who take steps to protect their skin when outdoors have been successful in reducing rosacea outbreaks, according to a new National Rosacea Society patient survey. Virtually all of the 739 respondents said they make an effort to shield their skin from the sun, and 88 percent of those said their efforts had been successful or somewhat successful in reducing their rosacea flare-ups.

"Even small amounts of sun exposure can cause problems for rosacea patients," said Dr. Alexa Boer Kimball, associate professor of dermatology at Harvard Medical School. "While everyone needs to be cautious about excessive exposure to the sun because of its link to skin cancer, rosacea patients need to be especially vigilant about blocking the sun's harmful rays."

Survey respondents cited a variety of protective measures they use to avoid the sun. Eighty-three percent said they use sunscreen and 70 percent said they wear sunglasses that block UVA rays. More than 60 percent mentioned staying in shaded areas and 55 percent reported they wear a broad-brimmed hat when outdoors. Half of those answering the survey said they stay inside at midday, and nearly a third said they wear long sleeves when outside. Sixteen percent noted they use a parasol or umbrella as a sun shield.

Dermatologists commonly recommend using a sunscreen with a sun-protection factor (SPF) of at least 30, and most survey respondents said they heed that advice. Forty-two percent noted that they use a sunscreen with an SPF 30, 20 percent said they use an SPF 50 and 14 percent said they use a product with an SPF greater than 50.

"The SPF of a sunscreen product is only one aspect of good sun protection," Dr. Kimball said. "Users need to remember to apply sunscreen at least 30 minutes before going out in the sun and to reapply sunscreen after swimming, perspiring or being in the sun for more than two hours."

Not all survey respondents had received the message about proper sunscreen usage. Only 49 percent said they always apply sunscreen a half hour before going out in the sun, as advised. Only 38 percent reported that they reapply the product as directed.

Eighty-nine percent of the survey respondents reported they use a sunscreen that protects against both UVA and UVB rays.