WOMEN’S HEALTH

PIGMENTATION IN SKIN OF COLOUR

Studies have confirmed that pigmentation is more common in skin of colour than European skin.1 South Asians seek more dermatology treatments for pigmentation than any other group.2 Post inflammatory hyperpigmentation or PIH, where skin responds to inflammation by overproducing melanin or pigment is particularly common in skin of colour.4

WHY IS SKIN OF COLOUR MORE PRONE TO PIGMENTATION?

Skin of colour has more active melanocytes and higher total melanin content than European skin.2 Tyrosinase (the critical enzyme for pigment production) activity is higher in skin of colour.5 The melanosomes are larger and degrade more slowly in skin of colour than white skin.6

The melanin itself is different in skin of colour, with a higher eumelanin (grey/dark brown shade) to pheomelanin (red and yellow in tones ) ratio than European skin.7

People with darker skin show propensity to inflammatory skin reactions,4 because of higher systemic IL-6, TNF-a, CRP and other cytokines and more inflammatory immune signals in the skin.4 This is why post inflammatory hyperpigmentation is common in skin of colour.8 The basement membrane in skin of colour is damaged more easily, pigment drops deep into the skin, causing long lasting pigmentation.4

People with skin of colour often use fewer photoprotective measures, and doctors discuss sunscreens to them less frequently.⁹

Research has traditionally been on white skin, and can’t be applied to skin of colour.10

MANAGING PIGMENTATION IN SKIN OF COLOUR

Managing hyperpigmentation in skin of colour presents unique challenges. Frequently used treatments such as hydroquinone, chemical peels, and laser therapy may precipitate post-inflammatory hyperpigmentation.11

A recent paper on sunscreen use in skin of colour highlighted that doctors aren’t talking about sun protection enough.2

The authors recommended that for skin of colour a sunscreen should be; at least SPF 30, broad spectrum, non greasy without white cast, and ideally containing anti-inflammatory and depigmenting ingredients.

Harsh products, dermabrasion, peels and lasers can make pigmentation worse.⁴

While ablative lasers have a high risk of post inflammatory hyperpigmentation, there is still a risk for non-ablative fractional laser, Q switched laser and picosecond laser.⁸ Before these procedures we try topical skincare along with sunscreen.11

The safest and most effective method for treating hyperpigmentation is reported to be blocking the activity of tyrosinase.11

4 n Butylresorcinol or 4NB is the most potent inhibitor of human tyrosinase available.14 Studies found strong depigmentation at 0.1% twice daily and 0.3% once daily. 84% of people get significant reduction in their pigmentation, even when used alone.15

A 40-week, randomised, double-blind, placebo-controlled clinical trial of 54 black patients investigated the safety and efficacy of 0.1% tretinoin in the treatment of post inflammatory hyperpigmentation. In terms of effectiveness, there was no doubt that tretinoin was superior to placebo in lightening the pigmentation.16 However, half of the patients in the study developed retinoid dermatitis, which is the concern with using prescription retinoids in skin of colour., retinal is a gentler alternative .

PIH can be especially severe after acne in skin of colour.18 Treating acne effectively yet gently is essential for preventing and managing PIH .

There is often an impaired skin barrier in skin affected by pigmentation.19 Consider adding in skin barrier repairing ingredients such as niacinamide,19 and ceramides to improve barrier function and reduce pigmentation to a topical skincare regimen.20

CONCLUSION

When treating people with skin of colour, opt for the least irritating topical products first with procedures and more irritating topicals for secondary use. Remember to reinforce the need for SPF and address any underlying inflammation or skin barrier impairment.

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DR GINNI MANSBERG

Dr Ginni Mansberg is a GP, TV presenter, podcaster, author and columnist. She is a physician specialising in women’s health, menopause and all things skin. She is also the co-founder and medical director of science-based cosmeceutical skincare brand, ESK.