Chiza Westcarr looks at managing post-inflammatory hyperpigmentation risks in ethnic skin
US minorities now represent more than half of America’s population under the age of one. The US population has become more ethnically diverse with greater than 35% of the population classified as non-white in 2010. In 2050 white Americans will comprise 46.3% of the population, a historic demographic milestone with profound political economic and social implications.
Alongside this there is also an increased mixing of the races, so when addressing post-inflammatory pigmentation as a result of acne or trauma, we are increasingly observing patients of varying hues and colours and of a much more diverse ethnic mix seeking solutions to their skin concerns. Racial mixing presents some interesting dermatological implications, and along with higher Fitzpatrick phototypes, must be treated with added caution.
Determing a patient’s heritage or racial background at face value is becoming a little more challenging, because with racial mixing, it is quite feasible to have a very fair-skinned patient present with blue eyes, but—due to their mixed heritage—have existing pigmentation concerns, or run an increased risk of post-inflammatory hyperpigmentation due to physician treatment selection. This is something that we need to make sure that we are aware of at the initial consultation and manage accordingly with prophylactic tyrosinase inhibitors for a two week minimum prior to the commencement of an in-clinic treatment strategy.
So what exactly do we mean by ethnic skin or skin of colour? It includes people of African descent, Asian, Indigenous Australian, people from the Sub-Continent, Pacific Islander, people of Middle Eastern and also Mediterranean descent. In this category we also include people of mixed heritage. These patients, outside of the typical concerns that most patients have—ageing, dryness, dehydration, blackheads, oily congested skin, dull lifeless skin, skin sensitivity—also experience melasma and post-inflammatory pigmentation as very real concerns.
Hyperpigmentation refers to a localised or more widespread increase of melanin in the skin caused by overactive melanocytes. In a dark skinned individual this creates a distinct darker colour than normal in the epidermis, and a greyish or blue colouration that is less defined in the dermis. It must be noted that in darker skins melanocytes are extremely active and sensitive to injury, whether it be sun induced or as a result of trauma.
Melasma occurs in a butterfly formation, usually bi-laterally on both sides of the face, typically affecting the forehead, malar region, upper lip, with macules or larger pigment patches featuring more prominently in the higher Fitzpatrick phototype than in fairer skinned patients.
There tends to be a genetic predisposition, and hormonal influences such as pregnancy, oral contraceptive pill and HRT are implicated. However, exposure to fragranced products such as perfumes, deodorants and fragranced soaps can also be possible causes. A link to hypothyroidism has also been established. Without sun protection, melasma is almost impossible to manage, so sun protection is encouraged.
PIH or post-inflammatory hyperpigmentation which occurs after an inflammatory eruption or cutaneous injury, is due to a melanocytic response to trauma causing increased production of melanin and distribution into the keratinocyte, where it settles over the nucleus like a cap.
Higher Fitzpatrick phototypes are more predisposed to PIH than lower Fitzpatrick phototypes, and for this reason skins must be well prepped, incorporating a tyrosinae inhibitor prior to in-clinic procedures. In a skin of colour, the causes of PIH are numerous – scratches, cuts, skin infections, allergic reactions, mechanical trauma, to name a few. Even hair growth, reactions to medication or inflammatory disorders such as eczema and psoriasis can result in PIH. Sometimes the very tools used to treat hyperpigmentation can actually exacerbate the condition. Incorrect laser and IPL settings, aggressive microdermabrasion, aggressive chemical peeling, can all result in PIH.
Physicians must appreciate that treatment protocols for a higher Fitzpatrick phototype must be different than that for a Fitzpatrick I to III, because of the increased risk of PIH as a result of too aggressive a treatment.
Hydroquinone has long been the gold standard treatment strategy for the management of hyperpigmentation. In prescription strength it is available at 4 to 6%, but it can also be obtained without a prescription in a 2% strength and typically it is not recommended to be used beyond three months due to tachyphylaxis and possible complications associated with long term use. In higher Fitzpatrick phototypes complications such as such as contact dermatitis, confetti like de-pigmentation and exogenous ochronosis have been observed with both short and long-term use. Where hydroquinone has been prescribed, during the aforementioned break, non-hydroquinone based products that contain tyrosinase inhibitors as well as melanin-transfer inhibitors are advised.
In the EU, throughout Asia and South Africa Hydroquinone has been banned in cosmetic over-the counter preparations because of the increased risk of exogenous ochronosis. It is however available by prescription in higher strengths, and in higher Fitzpatrick phototypes requires careful administration due to the aforementioned risks. There is growing consumer-led demand for products that are suitable alternatives to hydroquinone due to patient concern about Hydroquinone-associated rebound pigmentation and long-term risks. This has resulted in cosmeceutical formulatioins becoming more technologically advanced and more effective at managing the condition. Such preparations are ideal because they can be used long-term with no rebound pigmentation association and do not have the irritant profile that Hydroquinone has. Examples of such ingredients appear below and while it is by no means an exhaustive list, it provides a bit of an idea of the types of ingredients that are now being incorporated into clinical preparations available to medical practitioners and found to be successful in the management of hyperpigmentation.
Hyperpigmentation is an ongoing challenge and while there is no cure, it can certainly be effectively managed. Patients must be adequately counselled so they understand that patience is important in order to successfully manage their concern and the physician’s initial consultation is of utmost importance. Often the darker the Fitzpatrick phototype the more impatient the patient, because of the contrast in colour between the pigmented lesions and their skin. Aggressive treatment strategies can lead to a higher risk of complications, or a worsening of the condition, so it’s impoprtant that patients understand it can take up to six to 12 months for resolution to occur.
When analysing the process of melanogenesis, ingredients that target specific pathways can assist in the successful management of the condition. The importance of preparing the skin before in-clinic treatment cannot be over-estimated. Ingredients such as antioxidants, pigment inhibiting agents, retinoids, alpha hydroxy acids and anti-inflammatory ingredients along with sunscreen are a must.
Vitamin C, anti-inflammatories, and an effective sunscreen during the day all help prevent the initial inflammatory cascade in the keratinocyte which will assist in regulating the amount of tyrosinase enzyme up-regulated in the nucleus of the melanocyte in response to the inflammatory signalling. Retinoids also assist in the down- regulation of tyrosinase in the nucleus. The incorporation of tyrosinase inhibitors inhibit the interaction between tyrosinase and tyrosine in the melanosomes and thereby inhibit pigment production.
Niacinamide is very effective in aiding the prevention of pigment transfer into the keratinocyte while retinoids and hydroxy acids assist with exfoliation of pigmented keratinocytes.
In the darker or higher Fitzpatrick phototypes, getting patients onto a committed programme that involves sunscreen can be challenging, but without sunscreen successful management and in-clinic treatments are doomed to failure. The good news is that there is a growing number of elegant sunscreen formulations on the market that do not leave a chalky or white residue on a darker skin. Suitable products include micronised physical preparations that contain zinc and titanium oxide and chemical sunscreens that are fragrance free. No longer do they need to be heavy and occlusive, but ideally should be a 30 SPF minimum. Mineral make-up is another option or adjunct to using a sunscreen.
In clinic treatment
With regards to in-clinic treatments, lower Fitzpatrick phototypes do not require prior prepping on a pigment inhibiting agent. Pigment inhibition, however, is always recommended for Fitzpatrick III-VI to ensure that all post-inflammatory hyperpigmentation risks are minimised as a result of treatment. Establishing how the patient typically heals in response to trauma comes in handy‚does initial inflammation as a result of tissue injury eventually fade to a white scar or does it result in hyperpigmentation? Everyone, including patients who appear very fair skinned or those who do not appear to be a likely candidate for PIH, will know how their skin heals due to trauma. This is an indication of whether or not tyrosinase inhibition is required prior to in-clinic treatment.
The Wood’s lamp is a very effective tool to determine where pigment is located in the skin—whether it is epidermal or dermal. This lamp is extremely effective in assessing pigment distribution in lower Fitzpatrick phototypes, up to Fitzpatrick IV, but in higher Fitzpatrick phototypes, it is not possible to determine pigment depth.
Epidermal pigment is the easiest kind of pigmentation to address and topical agents such as hydroxy acids and retinoids encourage exfoliation.
To successfully address hyperpigmentation, a multi-modal approach is always better than utilising one particular treatment strategy. Examples of different in-clinic options to consider are microdermabrasion, skin needling, chemical peeling agents and specific laser therapies.
In conjunction with specific lasers, a series of epidermal chemical peels that include ingredients such as lactic acid, salicylic acid, retinoic acid as well as pigment targeting ingredients are successfully used to desquamate hyperpigmented epidermal cells and target hyperactive melanocytes. These options are less aggressive than traditional high acid-strength peels typically performed on lower Fitzpatrick skin types and have a reduced risk of post-inflammatory hyperpigmentation in higher Fitzpatrick phototypes when the skin is adequately prepped before hand. A milder, less inflammatory approach, beginning with a series of low strength acid peels is recommended.
Depending on the choice of agent used to manage hyperpigmentation, the use of anti-inflammatories as part of prescribed aftercare is also important to manage post-inflammatory pigmentation risks. Re-introducing a pigment management agent at this stage is also possible depending on the formulation, along with effective sun protection.
Regardless of skin colour, everyone wants to have the best skin that they can have. A skin that is healthy, a skin that has a strong barrier function, a skin that is fully functional and well hydrated. A skin that is the best that it can be. Understanding the nuances of diagnosis and treatment of skin of colour populations will help ensure that all patients receive optimal care.
Chiza Westcarr is the Global Clinical Education and Development Manager for Advanced Skin Technology, a Division of Device Technologies in Australia.