Is Acne the Same Around the World?

J Clin Aesthet Dermatol. 2024;17(9):16–22.

by Andrew Alexis, MD, MPH; Jerry Tan, MD; Marco Rocha, MD, PhD;
Delphine Kerob, MD; Ann’Laure Demessant, PharmD; Fatimata Ly MD;
Yan Wu, MD, PhD; Mukta Sachdev, MD; and Ichiro Kurokawa, MD, PhD

Dr. Alexis is with the Department of Dermatology, Weill Cornell Medicine, New York, New York. Dr. Tan is with Western University, Windsor in Ontario, Canada. Dr. Rocha is with the Department of Dermatology, Federal University of São Paulo in São Paulo, Brazil. Drs. Kerob and Demessant are with La Roche-Posay Laboratoire Dermatological Beauty in Paris, France. Dr. Ly is with the Dermatology Department at the University Cheikh Anta Diop of Dakar in Dakar, Senegal, West Africa. Dr. Wu is with the Department of Dermatology, Peking University First Hospital in Beijing, China. Dr. Sachdev is with the Department of Dermatology, Manipal Hospital in Bangalore, India. Dr. Kurokawa is with the Department of Dermatology at the Meiwa Hospital in Hyogo, Japan.

FUNDING: Funding for this study was provided by La Roche-Posay.

DISCLOSURES:  Dr Alexis has served as a consultant and/or advisory board member for Leo, Novartis, Galderma Laboratories LP, Sanofi Regeneron, Dermavant, Unilever, Beiersdorf, Valeant, L’Oreal, Bristol Meyers Squibb, Scientis, Bausch Health, UCB, Arcutis, Janssen, Allergan, Almirall, AbbVie, and Sol-Gel. Dr Tan has received grants, honoraria, or served as a consultant for Bausch, Boots Walgreens, Cipher, Cutera, Galderma, La Roche Posay, Novartis, Pierre Fabre, and Pfizer. Dr Rocha has served as an advisor and/or received honoraria from Galderma, Pierre-Fabre, Eucerin, La Roche Posay, and Leo Pharma. Dr Kerob and Dr Demessant are employees of L’Oreal. Dr Ly has served as consultant and received honoraria from La Roche Posay. Pr Wu and Dr Sachdev have served consultants for L’Oreal. Dr. Kurokawa has received research grants from Aisin Corporation and served as a consultant for L’Oreal.

ABSTRACT: Acne is a common skin disease associated with a range of sequelae. These include scarring and dyspigmentation, emotional and psychosocial disturbances, and occupational problems, in part because acne often manifests on the face, in addition to other body areas, and is highly visible. Worldwide, the prevalence of acne is estimated at 9.4 percent; it is most common in adolescents but also affects a relatively high proportion of adults. Early studies of acne epidemiology were conducted primarily in the United States and the United Kingdom. In more recent decades, data have been increasing for other areas of the world. There has also been more attention devoted to how acne may present and be managed in individuals with skin of color (i.e., the broad and diverse range of populations that self-identify as belonging to a non-White racial/ethnic group and share characteristics such as higher skin phototypes and propensity toward hyperpigmentation). This review seeks to highlight aspects of acne that may be unique to skin of color.

Keywords: Acne vulgaris, skin of color, ethnicity, race

Introduction

Acne vulgaris is a common inflammatory skin disease throughout the world, estimated to affect approximately 9.4 percent of the global population.¹ There are regional variations in acne that may be due to differences in environment (e.g., typical humidity, temperature, and climate) as well as skin types/ethnic/racial composition  of the population.^2,3 Acne is a multifactorial disease that is believed to include a strong inflammatory component along with follicular obstruction due to abnormal keratinocyte proliferation.⁴ Sebum quantity and quality and the microbiome­­­—including the balance of Cutibacterium acnes phylotypes—are considered  important factors in acne.⁵ Acne has long been considered a disease of adolescents, with a peak incidence occurring at age 15 to 20 years.¹ This seems to be fairly consistent throughout the world.¹ However, there is growing recognition of adult acne as a common subtype with unique characteristics. 

Generally, the differential diagnosis for acne is similar worldwide and includes other facial skin diseases such as rosacea, folliculitis due to gram negative bacteria, hidradenitis suppurativa, and demodecidosis. In some countries, infectious skin diseases can also be a consideration. For example, Paichitrojjana et al⁶ reported that 28.8 percent of newly diagnosed acne patients in Thailand also had Malassezia folliculitis. These authors note that acneiform lesions in patients with concomitant Malassezia folliculitis often present on the scalp or hairline and upper back; they may also be associated with pruritus.⁶ 

The clinical presentation of acne varies considerably across diverse populations and can be a challenge to effectively treat. Managing acne in individuals with skin of color (SOC) may pose unique challenges and specific considerations, such as  post-inflammatory hyperpigmentation (PIH) due to acne or secondary to irritation from treatment. In some cases, a greater risk for keloid or hypertrophic scarring secondary to acne may also be seen.^3,7 Women with SOC are also more likely to develop polycystic ovarian syndrome and have hormonal imbalances that contribute to acne.⁸ The term “skin of color” encompasses a diverse range of populations that includes individuals who self-identify as belonging to non-White racial/ethnic groups. Individuals with SOC characteristically have higher skin phototypes (e.g. III-VI) with associated melanocyte lability and therefore a higher risk of hyper- and hypopigmentation in response to injury and inflammation. SOC populations include, but are not limited to, individuals of African, Asian, Hispanic/Latino, and Middle Eastern descent.⁷ This will be the definition applied in this publication.

In recent years, clinical trials have been more inclusive of patients with SOC and subgroup analyses have been performed to compare the performance of treatments in different skin types.^9–15 To date, however, many of the existing acne guidelines have not included specific considerations for patients with SOC.^16,17 Further, guidelines are typically focused on prescription treatments despite growing evidence supporting the inclusion of skincare products.^15,18,19 The purpose of this publication is to examine the literature for variations and nuances in the epidemiology, clinical presentation, and management of acne in populations with SOC.^{13, 20–23}   

Examining acne in skin of color. Prevalence of acne around the world. Acne and its associated sequelae­ has consistently been reported among the top reasons people with SOC consult a dermatologist.^4,7,21,24  There is emerging evidence that post-adolescent acne is increasing. Han et al²⁵ studied the number of adult patients (≥25 years) in Singapore diagnosed  in an acne referral center over a 10-year period. The results showed an increase in cases from 4,447 (5.6%) in 2004 to 5,723 in 2013 (8.1%, Figure 1).²⁵ In addition, adolescent acne was more common in males, but adult acne was more common in females in the same study.²⁵ Analyzing data from the Global Burden of Disease Study 2019, Chen et al²⁶ confirmed that acne prevalence rates are “increased noticeably” across all age groups, including adults.

Some studies suggest that acne is more common in darker skin types compared to those with lighter skin.^3,27,28  In 2011, Perkins et al²⁷ compared the frequency of acne in “Caucasian, Asian, Continental Indian, and African American” women (N=2,895), and reported acne was observed in 37 percent of African American women (FST V-VI), 32 percent of Hispanic women (FST II-V) and 30 percent of Asian descent (FST II-VI) compared with 24 percent of Caucasian women (FST I-IV). Epidemiologic studies of acne from various world regions tend to study differing variables (e.g., prevalence, incidence, adolescents, and adults) which complicates comparison of regions; however, it is clear that acne affects populations worldwide. A United States study of Caucasian, Asian, Hispanic, and African American women reported ethnic-dependent differences in size of facial pores and epidermal architecture, with smallest pore size in Asians compared to the other groups.²⁹ Subsequently, Flament et al³⁰ evaluated pore size in 2,585 women from different countries and continents and observed very small and low density pores in Chinese women and large pores in Brazilian women, particularly those who had self-identified “large pores.”

Geographic and population-specific variations in access to care for acne have been reported. In a cross-sectional study of individuals with self-identified acne aged 18 or older (n=217), Mehta et al³¹ found that compared to White individuals, East Asian and South Asian individuals were significantly less likely to consult a healthcare professional (HCP) for acne and to get acne information from HCPs (P<0.01).³¹ Studies from Tanzania in the late 1990s involving 1,914 individuals from rural villages reported that just 10 to 33 percent with skin disease had sought treatment—delays and barriers to seeking effective treatment may help to explain high rates of acne sequelae.^32,33 Other Asian studies indicated adolescents were unlikely to seek medical help for acne (just 2.4% of adolescents in Hong Kong).^34,35 Regardless of location, analysis of the Global Burden of Disease data indicate that women have a disproportionately large negative effect due to skin diseases.³⁶ 

Geographic variations in acne epidemiology. Africa. When examining reported frequencies of acne in various world regions, rather than racial/ethnic populations, the African continent has both very high (90.7% in an urban adolescent population of Nigeria, n=418) and very low frequencies (5.4% of 8,008 individuals in rural Egypt) which are theorized to be related to rural versus urban differences, varying environmental factors, and degree of westernization.^37–39 Notably, however, there were relatively high rates of acne scarring (25%) and PIH (32%) even in the rural population who had predominantly mild-to-moderate acne.³⁸

Afro-Caribbean. Among 1,000 Afro-Caribbean individuals seen at a Jamaican clinic over a five-month interval, acne was the most common skin disease, occurring in 29.2 percent of the group.⁴⁰ Acne was also the most common skin disorder in Black Afro-Caribbean patients visiting Parisian dermatology clinics, occurring in a very similar rate to that in Jamaica (n=1,064; 29.2% in adults and 13.2% in children).⁴¹

Asia. Reports from Asia indicate that acne is very common in most countries (up to 91.3% depending on study). As with Africa, scarring is prevalent in Asians.^34,35 Reports from some Asian countries also suggest that adult acne is common. A study from Taiwan reported acne that persisted into adult years in 38 percent of women and 46 percent of men, although it should be noted that many other studies report adult acne is more common in women than men^.42,43 It is likely there are differences in acne epidemiology within Asia as well; a study by Li et al⁴⁴ in China found that 50.2 percent of primary and secondary school students and 44.5 percent of university undergraduates had acne, with higher proportions of acne in Southern China (46.3%) compared to Northern China (34.2%). 

Middle East. Studies in the Middle East report a greater than 50-percent frequency of acne in adolescents (53.4% of 517 Saudi Arabia students, 56.2% of 717 Saudi Arabia university students, 63.6% of 600 Turkish high school students, and 93.3% of 1,002 Iranian high school students).^45–49  Epidemiological data on the frequency of adult acne in this region are lacking, but there are studies on characteristics of adult acne from Turkey, suggesting it may not be uncommon in the Middle East.^50,51

Latin America. Acne is the most prevalent dermatologic disorder in Latin America.^52,53 A study of Latin American immigrants to Spain (n=706) found that acne was the second most common skin disease.⁴⁸ Interestingly, in 1998 Freyre et al⁵⁴ noted, “our clinical impression was that the frequency and severity of acne vulgaris was much lower among Peruvian adolescents, especially Indians, than that reported for other adolescent groups.” These researchers performed a cross-sectional study of 2,214 adolescents (aged 12 to 18 years) in Peru and reported an overall acne prevalence of 41.7 percent.⁵⁴ There were very low rates of moderate (<5%) or severe (<1%) acne.⁵⁴ Further, they found a significantly lower prevalence in Indian adolescents (P<0.002 vs. Mestizos or Caucasians).⁵⁴ However, a study from Argentina of 1,616 individuals consulting dermatologists found that 84 percent had inflammatory acne, of which 35 percent was moderate and 16 percent was severe.⁵⁵ This may be due to a large proportion of individuals of European descent in Argentina’s overall population.

Variations in the anatomic distribution of acne. The localization of acne may also vary somewhat by population. Comparing adult female acne in France, Senegal, and Mali, Poli et al⁵⁶ reported acne was more commonly on the mandibular area in adult women with darker skin phototypes: 87 percent versus 48 percent in those with lighter skin phototypes. These authors also found that the cheeks and chin were more likely to be affected in individuals with darker skin phototypes compared to lighter phototypes (91% vs. 61%; 84% vs. 43%, respectively).⁵⁶ In a Nigerian study, Anaba et al⁵⁷ found that while 80.4 percent of adult African women (aged 25 or older) had facial involvement only, 19.6 percent had extra-facial involvement. Another African study of 300 patients with acne (aged 12 to 52) seen in a dermatology clinic in Togo reported that 63.3 percent had back acne, 46.6 percent had acne on the neck, 45.3 percent had chest acne, and 20.0 percent had acne on their arms.⁵⁸ 

Gorelick et al⁵⁹ found that acne was more likely to be located within the hairline and on the chin in White subjects compared to Black, Hispanic and Asian, in a female adult population in the United States.However, pomade acne, which involves the upper forehead and temples, has been described as a variant of acne that is more common among patients of African descent, due to cultural hair care practices that can include products with comedogenic ingredients.⁶⁰ In addition, the use of corticosteroid-containing skin-lightening products by some populations with SOC has been associated with steroid acne.⁶¹ A study in South Africa found that steroid-induced acne was a common subtype, occurring in 12.7 percent of individuals with acne, highlighting the need to take a thorough history of skin care and identify potential contributing factors, including skin lightening products.⁶² Clinically, comedones are absent in steroid-induced acne.

Inflammation and other attributes in skin of color. Inflammation. In a study involving almost 3,000 adult women from Los Angeles, USA; London, UK; Akita, Japan; and Rome Italy, rates of acne differed by ethnicity with 37 percent of Black individuals with acne, 32 percent of Hispanic, 39 percent of Asian, 24 percent of White individuals, and 23 percent of continental Indian women.²⁷ However, these differences could be attributable to other factors (i.e., geography, selection, etc.) than race or ethnicity. The same study reported inflammatory acne occurred more frequently than comedonal among Asian women (20% vs. 10%) in contrast to the presentation in White women (14% comedonal vs. 10% inflammatory).²⁷ The authors concluded that “acne prevalence and sequelae were more common in those with darker skin types, suggesting that acne is a more heterogeneous condition than previously described.”²⁷ 

In a histopathologic study examining biopsies of facial acne among Black women, Halder et al⁶³ observed that inflammation was present in all types of acne lesions, including comedones.⁶⁰ Duquia et al⁶⁴ from Southern Brazil also reported a more inflammatory acne phenotype in SOC versus White individuals.

Skin oiliness. Oily facial skin, characterized by excess sebum production, is associated with a variety of dermatologic problems including acne (Figure 1).^65,66 When combined with oily skin, acne can be challenging to treat because sebum can mix with topical medications and/or cosmetics which in turn may interrupt the film-forming properties needed for action.⁶⁶ Studies evaluating population differences in sebum production or skin oiliness are limited. However, the pore size studies discussed above reported a direct relationship between pore size and sebaceous gland activity.^30,67 In a study of 1,787 Chinese women, oily skin was observed in 25.6 percent.⁶⁸ Dermocosmetics with ingredients that may reduce skin oiliness may be beneficial in acne patients with SOC. A double-blind, placebo-controlled study in Japanese patients (n=100) found that niacinamide 2% significantly reduced sebum excretion after 4 weeks of use.⁶⁹ Dermocosmetics may diminish surface skin oils, and those with ingredients such as niacinamide, zinc, and L-carnitine should be selected.^69–72

Sensitive skin. Sensitive skin can be a problem in some population segments. It is thought to be linked to an impaired skin barrier.^15,73 Sensitive skin symptoms include dryness/flaking/peeling, burning/pain, pruritus, and tingling sensations.⁷⁴ Goh et al¹⁵ note that there is a general perception that Asian skin is more irritation-prone following application of topical agents compared to other skin types, such as White skin. Further, Asian skin has higher neurosensitivity to insults versus White or Black skin.¹⁵ Sensitivity may be greatest in the East Asian population.⁷⁵ Skin sensitivity is also affected by the aging process; given the significant increase in the number of acne cases in adults, this must be taken into account when choosing medications and dermocosmetics.⁷⁶ A holistic skincare routine may be used to reduce the potential for irritation due to prescription products and potentially enhance adherence.⁷⁴ Moisturizers with acne-targeting dermocosmetic ingredients can improve tolerability by reducing dryness and stinging sensations due to barrier disruptions, which translate to adherence.¹⁵ 

Frequency of acne-associated complications. PIH and scarring. Both acne scarring and PIH are frequent complications of acne in patients with SOC (Figure 2). In the previously discussed study of women by Perkins et al²⁷, PIH was observed in more than half of African American and Hispanic women (65% and 48%, respectively) compared to 10 percent to 25 percent in the other population segments. Atrophic scarring was also more frequent in African American and Hispanic women versus the other ethnicities.²⁷ In an adult African female population (25 years or older) with predominantly mild to moderate acne, Anaba⁵⁷ observed acne scarring in 87.5 percent of patients and PIH in 65.3 percent.⁵⁷ An African study by Saka et al⁵⁸ (N=300, ages 12–52 years) reported 11 percent of patients had atrophic acne scars and 83 percent had PIH. The relatively lower proportion of acne scarring may have been due to the younger age of the population (mean 23.6 years) since 69.3 percent of the patients were younger than 25 years.⁵⁸ PIH has been reported to be very common (56.6%) in primary school children and adolescents in Eastern Saudi Arabia.⁴⁶ PIH is also very common throughout most Latin American countries and is a source of intense concern on the part of patients.⁷⁷ The postacne hyperpigmentation index (PAHPI), which evaluates the degree of PIH, can be useful clinically to determine acne and PIH severity.⁷⁸ 

When nodules and cysts are present, they often lead to hypertrophic scarring.^23,69 Child et al⁷⁹ studied Black patients attending a dermatology clinic in London and found that acne was the most common disease and hypertrophic scarring was the fifth most common diagnosis occurring in 4.1 percent of the adult patients in the group (n=274).⁸⁰  

Both PIH and scarring often pose greater concerns to the SOC patients than the active acne lesions.^81,82 Pathmarajah et al⁶⁰ note that PIH “frequently goes unrecognized by clinicians, which is likely related to the lack of representation of skin of color in dermatology photography resources.” These authors also emphasize that pigmentary changes linked to acne often last far longer than the active acne lesions, with epidermal pigment requiring 6 to 12 months or longer to resolve and dermal pigmentation capable of lasting for years.⁶⁰ In some cases, PIH will fade in 3 to 18 months⁸³; however, in a multi-country survey of Asian dermatology patients (N=324), more than half had PIH that lasted more than one year and approximately a quarter (22.3%) had PIH for five years or more.⁸² Atrophic acne scars of recent onset may resolve spontaneously naturally, but many are persistent.⁸⁴ Tan et al⁸⁵ recently documented that acne scarring had a significant psychosocial impact, even when mild in severity.⁸⁴ In Japan, acne scars were classified as mini-scars (atrophic scars ≥0.5mm and <2mm in diameter) atrophic scars (≥2mm in diameter), and hypertrophic scars.⁸⁵ All patients with scars had mini-scars; 61.2 percent and 14.2 percent of 240 had atrophic scars and hypertrophic scars, respectively. 

Saka et al⁵⁸ studied the impact of acne in Lome, Togo in 300 patients aged 12 to 52 years consulting dermatology clinics. They found some degree of reduced quality of life (QOL) in all patients, with a positive correlation between acne severity and worsening QOL.⁵⁸ Specifically, acne severity negatively impacted patients relationships, avoidance behaviors, and self-perception.⁵⁸ In a large study of PIH (n=324) in seven Asian countries, almost one third (32.2%) of patients felt their PIH was more bothersome than the acne lesions present.⁸² Further, the degree of bother increased with increasing PIH severity.⁸² Schuster et al⁸⁶ reported that patients with PIH also face social stigmatization.

Tan et al evaluated the impact of atrophic acne scarring (N=723) and found that almost the same proportion of patients with mild to moderate rated their acne scars as creating a “very” or “extremely” large concern (19.3% and 20.1%, respectively) on the Dermatology Quality Life Index (DLQI).⁸⁷ For those with severe acne, 34.0 percent felt their scars had a major impact on their life quality. A large proportion of patients reported being self-conscious (68.0%) and expressed fear that the scars were permanent (74.8%). Although awareness of newer treatment modalities for acne scarring was low, a Nigerian study (N=50) found that 86 percent of patients were willing to pay for scar treatment.⁸⁷ In an online survey study comparing photos of images with no scars and those digitally altered to have scars, individuals in the scar photos were negatively perceived compared to those without (P<0.05).⁸⁸ To date, the best strategy to minimize scar formation is early and efficacious acne treatment during the acute inflammatory phase to reduce inflammation. 

Patients with darker skin types should be educated about the need for photoprotection, since PIH can be worsened by light exposure (UVB, UVA, and visible light).³ Daily broad-spectrum sunscreens should be used to minimize the potential for PIH and to prevent further pigmentation. In addition to sunscreens, a variety of skincare regimens and products have been shown to improve the appearance of PIH. For example, in an open-label, intra-individual study that included patients with mild acne (N=43) who applied a dermocosmetic cream (DC), comprising salicylic acid, lipohydroxy acid, niacinamide, procerad, mannose and APF (a biomass of Vitreoscilla filiformis grown in La Roche-Posay Thermal-Spring-Water culture medium) along with an acne-dedicated cleanser (Effaclar® Purifying foaming gel and Effaclar® Duo+; La Roche-Posay Laboratoire Dermatologique) twice daily for 56 days, 51 percent had a phototype V and 19 percent had phototype VI. In participants with PIH, there was a significant decrease of the average number of PIH marks by Day 56 (P<0.001, Figure 3).⁸⁹ 

It is also important for clinicians to be aware of the influence of social media on acne and its treatment, particularly in individuals younger than 25 years.⁹⁰ Further, a Chinese study evaluated the quality of content on social media (querying TikTok) and reported that the top 100 videos had “serious to potentially important shortcomings.”  Thus, dermatologists and other healthcare professionals should be aware of this influence and ask patients routine questions to assess their understanding and knowledge of acne. In some cultures, use of home remedies— such as applying turmeric or toothpaste, facial waxing for hair removal, and application of natural and occlusive oils—occurs and can lead to irritant contact dermatitis.^91–96 

Conclusion

There is an increasing recognition of population variations of acne and nuances in SOC patients. More research and education into variations of acne across diverse populations will allow for more individualized care and, presumably, improved therapeutic outcomes.

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