For example, in patients with Fitzpatrick skin types V and VI, the desired treatment outcome is not only the resolution of acne but also the resolution of hyperpigmentation, said Dr. Alexis, chairman of the department of dermatology at Mount Sinai St. Luke’s and Mount Sinai West, New York, N.Y.
“Postinflammatory hyperpigmentation is often the driving force for the dermatology consult” in individuals with skin of color,said at the summer meeting of the American Academy of Dermatology. “They may be just as concerned about their dark spots as underlying acne,” he noted, citing a study that he coauthored ( ).
In the study – a survey of patients with acne to determine which treatment outcomes were most important – 41.6% of the nonwhite female patients reported that clearance of postinflammatory hyperpigmentation was the most important goal, compared with 8.4% of white female respondents (P less than .0001).
As with so many conditions that require a prolonged course of treatment, setting expectations is a key part of the dermatologist’s communication with the patient, Dr. Alexis continued. “Make sure that they know that you are going to treat the dark spots,” and that it will take time “to get to the desired endpoint.”
It’s important to avoid undertreating patients, especially darker-skinned patients, where ongoing subclinical inflammation may contribute to hyperpigmentation. Even in lesions that appear grossly noninflamed, biopsies may find histological evidence of inflammation, with increased T-cell infiltration of the pilosebaceous units, Dr. Alexis said.
However, there’s always a balancing act in determining how aggressively to treat patients, he added. Dermatologists have to be aware of the risk of hypertrophic scar formation in darker-skinned individuals, especially in truncal areas.
When addressing acne, step one is to aggressively reduce acne-associated inflammation to reduce potential sequelae. This can be done with any of a number of agents, such as retinoids, benzoyl peroxide, dapsone, azelaic acid, and even intralesional corticosteroid injections, he said.
“All agents have been considered in darker skin types,” he said, noting that “retinoids are particularly important because they can also treat postinflammatory hyperpigmentation.” Tretinoin 0.1% cream and tazarotene 0.1% cream are both good choices, he added.
Adapalene in a fixed combination with benzoyl peroxide has been studied in darker-skinned patients, with no difference in tolerability or higher incidence of pigmentary sequelae than in lighter-skinned patients, he pointed out.
Dapsone 5% and 7.5% have also been studied in patients with darker skin, and both concentrations showed comparable results for safety and efficacy.
The thinking about second-line agents can shift a bit when treating acne in darker skin. For example, azelaic acid as a 20% cream or 15% gel can be a good choice and can be helpful in treating postinflammatory hyperpigmentation, but azelaic acid is “not as good an antiacne agent as retinoids,” Dr. Alexis said.
Patients should understand that any of these choices are primarily acne-directed treatments, to be deployed over the first 3-6 months of treatment. Then, beginning at about the 3-month mark and continuing for up to a year, hyperpigmentation can be addressed. “Really emphasize the duration of treatment,” when treating hyperpigmentation, Dr. Alexis advised.
Once the acne is under control and hyperpigmentation can be assessed on its own, dermatologists can consider whether bleaching agents are appropriate. “Should they be used? If so, how?” he asked.
Bleaching agents can be effective, said Dr. Alexis, who recommends lesion-directed rather than broad-field therapy, unless there are many larger hyperpigmented macules. “The more common scenario is smaller, more distributed lesions,” he said. “Superficial chemical peels, if used with caution, can be a good adjunct,” to bleaching agents, he added.
Coming down the road are topical nitric oxide preparations, which he said are looking good for darker skin in clinical trials.
“The key to great outcomes is to initiate a combination regimen that targets inflammation and reduces hyperpigmentation,” said Dr. Alexis. Then, he advised, minimize irritation but don’t undertreat, consider adjunctive chemical peels, and above all, “set realistic timeline expectations.”