'Subtype-directed' approach targets rosacea

January 1, 2005

New York - The four recently defined subtypes of rosacea are likely caused by different pathogenic factors, and thus respond to different therapeutic regimens, according to Michelle T. Pelle, M.D.

New York - The four recently defined subtypes of rosacea are likely caused by different pathogenic factors, and thus respond to different therapeutic regimens, according to Michelle T. Pelle, M.D.

Consequently, dermatologists should employ a "subtype-directed approach" when treating rosacea - incorporating the available topical, oral, laser and light therapies, says Dr. Pelle, who spoke here at an American Academy of Dermatology (AAD) press conference held in support of National Healthy Skin Month.

"Characterizing the subtype of rosacea provides a clearer approach to therapy for that patient," Dr. Pelle says.

"I call it 'redefining,' because we used to think of rosacea in a staged type of progression, where one stage moved to the other, but in fact, that doesn't happen," Dr. Pelle says.

A gentle and broad-spectrum sunscreen applied daily is the "standard of care" for all patients, regardless of subtype, and even before treatment starts, time should be taken to identify factors that trigger rosacea signs and symptoms, including temperature, wind, spicy food, alcohol and emotional factors.

Strategies vary Beyond sunscreen use and trigger avoidance, however, the recommended management strategies vary widely. For example, barrier protection is particularly important in the erythematotelangiectatic subtype patients, most of whom have very sensitive skin.

"It's important that they know gentle moisturizers must be a part of their regimen," Dr. Pelle says.

Initial topical therapies include several FDA-approved choices, including metronidazole (0.75 percent and 1 percent), sulfamethoxizole 10 percent and sulfur 5 percent, and azelaic acid 15 percent; most are generally gentle on the skin. Benzoyl peroxide, while contraindicated in patients with sensitive skin, can be helpful in the papulopustular and phymatous subtypes, according to Dr. Pelle.

Oral therapies include tetracyclines, useful for their anti-inflammatory properties; metronidazole; hormonal therapies; and isotretinoin for more difficult cases that don't respond to the standard of care.

Topical retinoids Topical retinoids have clearly demonstrated benefit in rosacea.

"Some dermatologists choose to avoid them, because they are more difficult to use, but over the long term, they really do make a difference for these patients," Dr. Pelle says. "In my experience, at one month you get an improved skin texture, at four months flushing is much less frequent, and at one year there is a normal flush response, substantially decreased redness and few to no flares requiring tetracyclines."

"I tell almost every patient I see that we are going to eventually transition them to tretinoin," Dr. Pelle adds. "Whether they have started with a combination therapy that's medical, or whether they have had laser or light therapy, they always finish up with a gentle sunscreen and a topical retinoid. That's the best way, in my opinion, to maintain them."

Vascular laser therapy is useful in treating the telangiectasia and erythema associated with rosacea. Choices include standard and long pulsed-dye laser (PDL), potassium-titanyl-phosphate (KTP) lasers, diode frequency-doubled lasers and the Nd-YAG lasers.

Dr. Pelle says she most recently has used the variable-pulsed PDL (10 mm, 10 ms, 7.5 J/cm2): "With a longer pulse duration, we can deliver enough energy to vaporize the blood vessel, but over a longer duration to decrease purpura," she explains. "We damage the tissue less, and deliver the same amount of energy over a longer period of time."