Botox and Injectable Fillers Appear Safe for Darker Skin

WASHINGTON — Accumulating data suggest that botulinum toxin and injectable fillers are as safe and effective in ethnic minorities as they are in white patients, Dr. Gary Monheit said at the annual meeting of the American Academy of Dermatology.

Although most of the evidence supporting the use of botulinum toxin and fillers has come from whites, leading to hesitation about use in darker skin types, those modalities are likely to be the first ones used in ethnic minority patients, because the initial sign of aging in darker skin tends to be volume loss, leading to frown lines, marionette lines, nasolabial folds, and upper forehead lines, said Dr. Monheit of the University of Alabama, Birmingham.

Botox injection is the most common cosmetic procedure, with some 2.8 million Americans receiving a treatment in 2004, according to Dr. Monheit. Almost 19% of the injections were in minorities (8.5% in Hispanics, 6.2% in blacks, and 4.2% in Asians), he said.

The most commonly injected areas for white patients are the forehead and brow area. In black patients, crow's feet generally aren't a concern; more commonly, the brows, forehead, and frown lines are targeted.

Variables to consider with ethnic minorities include facial structure and musculature; the histology of thick skin, collagen, and elastin fibers; atrophy resulting from photoaging; and "sociocultural factors that may make one not want to totally paralyze the face" and lose certain expressions, Dr. Monheit said.

Botox dosages have been standardized for whites but not for other ethnic groups, which has led to questions of safety and effectiveness in those minorities, he said.

A study led by Dr. Pearl E. Grimes of the University of California, Los Angeles, may give dermatologists some direction, he said. The trial was funded by Allergan Inc. and has not yet been published. A total of 31 black women, aged 18–67 years and with Fitzpatrick skin types V and VI, were randomized to 20 or 30 units of Botox, in five divided doses to the glabella. They were assessed at 30, 60, 90, and 120 days.

Their outcomes were compared with results from a dose-ranging study in whites that was also funded by Allergan (J. Derm. Surg. 1992;18:17–21).

The therapy's longevity appeared to be the same in the black women as in white women, Dr. Monheit noted.

At 1 month, 94% of those receiving 20 units and 100% of those receiving 30 units were considered responders. The response dipped to 20% for 20 units and 40% for 30 units at day 90. Patient satisfaction was 100% on day 30 and 60% on day 120.

There was less than a 4% incidence of adverse events—mainly headache and tingling—and the authors concluded that Botox is safe, efficacious, and well tolerated in women of color, he said.

When using fillers in minorities, it is important to consider what and how much volume is missing, and what areas are to be treated.

Again, there has been little published specifically on the safety and efficacy of the older fillers, such as collagen and hyaluronic acid-based fillers, Dr. Monheit said.

Anecdotally, there have been reports of more bruising, increased postinflammatory hyperpigmentation, keloids, and granuloma.

"All of these are fears that patients bring to us, but at this point there's no real solid data to counteract these [fears]," Dr. Monheit stated.

A postmarketing study—funded by Genzyme Corp. and Inamed Corp. and led by Dr. Grimes and Dr. Monheit—may provide some answers.

The multicenter trial, the results of which have not been published, was done at the behest of the Food and Drug Administration. The agency was concerned about the side effects of hyaluronic acid-based fillers in darker skin types. In the trial, 55 nonwhites—the preponderance Hispanic and Asian, with about 10% African American—were compared with 261 white controls.

A total of 27 minority patients received Zyplast and 28 were given Hylaform. They were compared with 128 white Zyplast recipients and 133 who received Hylaform.

According to Dr. Monheit, the results were similar for both fillers in the minorities when compared with results in the white patients at 2 and 12 weeks.

There were no keloids or granulomas in minority patients. Interestingly, both fillers were better tolerated in nonwhites. Some of the initial adverse events reported by white patients—such as erythema—seem to be masked by darker skin, he said.

It is not clear whether these results can be extrapolated to other fillers or for other areas of the face, and more questions will likely arise as new fillers—especially those that stimulate collagen development—come to the market, Dr. Monheit said.