Rosacea: Who gets and causes

Who gets rosacea?

• Between 30 and 50 years of age

• Fair-skinned, and often have blonde hair and blue eyes

• From Celtic or Scandinavian ancestry

• Likely to have someone in their family tree with rosacea or severe acne

• Likely to have had lots of acne — or acne cysts and/or nodules

Women are a bit more likely than men to get rosacea. Women, however, are not as likely as men to get severe rosacea. Some people are more likely to get rosacea, but anyone can get this skin disease. People of all colors get rosacea. Children get rosacea. 

What causes rosacea?

Scientists are still trying to find out what causes rosacea. By studying rosacea, scientists have found some important clues:

• Rosacea runs in families. Many people who get rosacea have family members who have rosacea. It is possible that people inherit genes for rosacea.

• The immune system may play a role. Scientists found that most people with acne-like rosacea react to a bacterium (singular for bacteria) called bacillus oleronius. This reaction causes their immune system to overreact. Scientists still do not know whether this can cause rosacea.

• A bug that causes infections in the intestines may play a role. This bug, H pylori, is common in people who have rosacea. Scientists cannot prove that H pylori can cause rosacea. Many people who do not have rosacea have an H pylori infection.

• A mite that lives on everyone’s skin, demodex, may play a role. This mite likes to live on the nose and cheeks, and this is where rosacea often appears. Many studies found that people with rosacea have large numbers of this mite on their skin. The problem is some people who do not have rosacea also have large numbers of this mite on their skin.

• A protein that normally protects the skin from infection, cathelicidin, may cause the redness and swelling. How the body processes this protein may determine whether a person gets rosacea.