Asians comprise more than half of the earth’s population. With changing demographics in the United States skincare professional will come in contact with an increasing number of patients exhibiting this ethnic skin type. An understanding of the cutaneous problems exhibited by this increasing group of patients is of paramount importance. Asian patients exhibit Fitzpatrick skin types III-V and treating this population is rarely written about. When evaluating the skin differences between the various ethnic groups several bio-physical skin parameters are evaluated. The most obvious difference between ethnic groups is skin color due to the presence of the photo-protective pigment melanin. Other parameters to be considered are thickness of the stratum corneum (SC) and trans-epidermal water loss (TEWL).
Changes in the physical properties of the skin, (SC) and (TEWL), show that with aging, darker skin types retain younger looking skin properties than do lighter skinned individuals. This may be because these ethnic skin groups have a more compact stratum corneum (SC) and as a result have increased skin barrier function despite lower ceramide levels. According to Rawlings et al, upon chemical and mechanical challenge the SC barrier function is reported to be stronger in subjects with darker skin. One has to remember that barrier function relates to total skin architecture and not just ceramide levels. Recent studies suggest that Asian skin types may be more sensitive to exogenous chemicals probably due to a thinner SC and a higher eccrine (sweat) gland density. It is therefore important that consumers and skincare professionals evaluate the types of products that are best suited as treatment options and for daily use by these individuals.
Asians are prone to many of the pigmentary disorders seen in other ethnic groups. Melasma, the so-called “mask of pregnancy”, freckles and lentigines are typical epidermal hyperpigmentary disorders, while nevus of Ota and acquired bilateral nevus of Ota-like lesions are common dermal hyperpigmentary disorders. The nevus of Ota was originally described by Ota and Tanino in 1939 and is described as a tumor like accumulation of melanocytes in the dermis. It occurs most frequently in Asian populations with an estimated prevalence of 0.2%-0.6% for Japanese persons. It is uncommon in whites but may be seen in Africans, African-Americans, and East Indians.
Clinically, it presents as a blue or grayish-blue patch on the face. It may be congenital or acquired, and it follows the distribution of the ophthalmic and maxillary branches of the trigeminal nerve. Although its presence within the same family is rare, its prevalence among different populations suggests genetic influences. Nevus of Ota can cause facial disfiguration and in rare cases develop into melanoma, which can be life threatening. This condition also varies as to its onset. The earliest onset of this condition is in infancy with as many as 50% occurring at birth. The second period of onset is adolescence. Its appearance in adulthood and in the elderly is rare.
Similar to the African-American population, the Asian-American population is prone to post-inflammatory hyperpigmentation (PIH). With increasing use of lasers for skin re-surfacing and other cosmetic procedures, prevention of PIH is of great interest. Another source of PIH in the Asian population is acne, which is common in Asians. The goal in the treatment regimen of PIH is to eliminate the offending source of the inflammation. One of the ideal treatments for acne in this population are azelaic acid based products. Azelaic acid is a natural product derived from grain that is an excellent skin bleaching agent without the side effects seen with hydroquinones. Other than its ability to lighten areas of PIH it is also a first line treatment for adult acne as well as other skin conditions like rosacea and eczema, and brown/age spots as a result of sun damage. This acid works by inhibiting the action of the enzyme tyrosinase which converts tyrosine into the skin pigment melanin and thus lightens the affected area of hyperpigmentation. In addition to its skin lightening ability azelaic acid is also bactericidal for the Proprion bacillus, the bacteria responsible for acne as well as an anti-DNA action that may reduce the scarring that may follow outbreaks of acne. It is very important that the consumer and health care professional choose the right type of azelaic acid product. This acid, other than the above mentioned qualities, also has antioxidant properties. As such, it is prone to oxidation and deactivates on exposure to the air rendering in effective. Look for products that are a single dose, individually sealed unit packaging. In this way, you are guaranteed that the cream you are using is going to be full strength each time it is applied.
In conclusion, every once in a while there exists a natural product that does what it promises to do. Azelaic acid is a multi-functional botanical that will lighten brown spots and even-out skin tone similar to hydroquinones without any of the associated side effects. It is effective against adult acne, rosacea, eczema, and in a few human clinical studies it has been shown to be effective against certain pre-malignant skin lesions like lentigo maligno. The multi-functionality of azelaic acid makes it an excellent all-in-one product that is both therapeutic and cost effective. In addition to therapeutic treatments for hyperpigmentary disorders, it is very important to protect the skin against the damaging effects of environmental pollutants like the suns UV rays which can worsen these lesions. Consumers should look for moisturizing products that contain high levels of antioxidants, like pure lycopene, that protect the skin from the aging effects of environmental contaminants and contain sunscreens that protect the skin from the damaging and aging effects of the sun’s UVA and UVB rays.