Racial (ethnic) differences in skin properties may explain racial disparities seen in dermatologic disorders and provide insight into appropriate differences in the management of these disorders. However, racial differences in skin have been minimally investigated by objective methods and the data are often contradictory. Objective methods studied include transepidermal water loss (TEWL), water content (WC), corneocyte variability, blood vessel reactivity, elastic recovery/extensibility, pH gradient, lipid content, surface microflora, microscopic evaluation of mast cell granules, and confocal microscopy. The majority of the evidence (six out of eight studies) indicates that TEWL is greater in Black skin compared with White skin. TEWL measurements of Asian skin are inconclusive as they have been found to be equal to Black skin and greater than Caucasian skin, equal to Caucasian skin, and less than all other ethnic groups in different studies. Racial differences in WC, as measured by resistance, capacitance, conductance and impedance, are also inconclusive as the data are contradictory. While the evidence regarding corneocyte desquamation is minimal, one clinically provocative observation is that Blacks have a 2.5 times greater spontaneous desquamation rate compared with Caucasians and Asians, possibly accounting for an increased frequency of xerosis seen clinically in Blacks. With regards to blood vessel reactivity, studies can not be compared to each other because each uses different vasoactive substances. However, each study, except for one study comparing Hispanics and Whites, and another comparing Japanese and German women, reveal some degree of racial variation in blood vessel reactivity. It has been demonstrated that the pH of Black skin is less than White skin; however, the studies that have demonstrated this have done so under different skin conditions and on different anatomic sites. Racial differences in lipid content are inconclusive. Additionally, there is insufficient and conflicting evidence to make conclusions regarding racial differences in skin biomechanics and skin microflora. Microscopic evaluation reveals that Black skin contains larger mast cell granules, and differences in stuctural properties and enzymes of mast cells compared with White skin, possibly accounting for differences in pruritus experienced by the individuals of these racial groups. There exists substantial evidence to support that Black skin has a higher TEWL, variable blood vessel reactivity, decreased skin surface pH, and larger mast cell granules compared with White skin. Although some deductions have been made about Asian and Hispanic skin, further evaluation needs to be done. Differences in WC, corneocyte desquamation, elastic recovery/extensibility, lipid content and skin microflora, although statistically significant, are inconclusive.

The United States has become progressively more multicultural, with the ethnic population growing at record rates. The US Census Bureau projects that, by the year 2056, greater than 50% of the US population will be of non-Caucasian descent. Ethnic patients have different cosmetic concerns and natural features that are unique. The cosmetic concerns of ethnic patients also differ as the result of differences in skin pathophysiology, mechanisms of aging, and unique anatomic structure. There is no longer a single standard of beauty. We must now adapt to the more diverse population and understand how to accommodate the diversity of beauty in the United States. Ethnic patients do not necessarily want a Westernized look because what constitutes beauty is determined by racial, cultural, and environmental influences. We as leaders in skin care must understand these differences and adapt our practices accordingly. This article will focus on the differences in aging in different ethnic populations and highlight procedures unique to skin of color.

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Background: DaxibotulinumtoxinA for Injection (DAXI) is a novel botulinum toxin type A formulation in clinical development. A phase 2 dose-ranging study identified an optimal dose and demonstrated efficacy with a median duration of 24 weeks. Methods: In two phase 3, multicenter, randomized, double-blind, placebo-controlled studies (SAKURA 1 and SAKURA 2), subjects with moderate or severe glabellar lines at maximum frown were assigned randomly to receive placebo or 40 U of DAXI. Glabellar lines were evaluated at least every 4 weeks for at least 24 weeks until severity returned to baseline (≤36 weeks). Results: Overall, 609 subjects were enrolled (DAXI, n = 405; placebo, n = 204). DAXI was significantly more effective than placebo in achieving the primary efficacy outcome (≥2-point improvement in glabellar line severity at maximum frown at week 4 according to both investigator and subject ratings): 73.6 percent versus 0.0 percent (SAKURA 1), and 74.0 percent versus 1.0 percent (SAKURA 2) (both p < 0.0001). Composite investigator and subject ratings of maximum frown after DAXI treatment showed that glabellar line severity of none or mild was maintained for a median of 24.0 weeks (SAKURA 1) and 23.9 weeks (SAKURA 2), and glabellar line severity did not return to baseline levels for a median of 27.7 and 26.0 weeks, respectively. DAXI was generally well tolerated, with the most common adverse events related to DAXI treatment being headache (SAKURA 1, 7.0 percent; SAKURA 2, 5.9 percent) and injection-site pain (5.0 percent and 2.4 percent, respectively). Conclusions: Results from both studies were highly consistent. DAXI may offer a prolonged duration of response (median, ≥24 weeks) and is generally well tolerated. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, I.

Background: Given the recent boom of the cosmetic industry, there is a wealth of new products available to patients and physicians, including soft-tissue fillers. Bio-Alcamid polyacrylamide gel (Polymekon, Milan, Italy) is a filler that has potential to cause adverse reactions. Observations: Two patients who had previously been treated with Bio-Alcamid outside of the United States presented with different manifestations of inflammatory responses to the product. These reactions were challenging to treat. Conclusions: Despite claims of safety, Bio-Alcamid and possibly other soft-tissue fillers available worldwide have the potential to cause adverse reactions. Physicians should be aware of the various presentations and treatment options for these reactions.