SKINIPEDIA - Skin Encyclopedia: Acne Vulgaris

Acne Vulgaris - A Disease of Western Civilization

A study by: Loren Cordain, PhD; Staffan Lindeberg, MD,PhD; Magdalena Hurtado, PhD; Kim Hill, PhD; S. Boyd Eaton, MD; Jennie Brand-Miller, PhD

 

Background  In westernized societies, acne vulgaris is a nearly universal skin disease afflicting 79% to 95% of the adolescent population. In men and women older than 25 years, 40% to 54% have some degree of facial acne, and clinical facial acne persists into middle age in 12% of women and 3% of men. Epidemiological evidence suggests that acne incidence rates are considerably lower in nonwesternized societies. Herein we report the prevalence of acne in 2 nonwesternized populations: the Kitavan Islanders of Papua New Guinea and the Aché hunter-gatherers of Paraguay. Additionally, we analyze how elements in nonwesternized environments may influence the development of acne.

Observations  Of 1200 Kitavan subjects examined (including 300 aged 15-25 years), no case of acne (grade 1 with multiple comedones or grades 2-4) was observed. Of 115 Aché subjects examined (including 15 aged 15-25 years) over 843 days, no case of active acne (grades 1-4) was observed.

Conclusions  The astonishing difference in acne incidence rates between nonwesternized and fully modernized societies cannot be solely attributed to genetic differences among populations but likely results from differing environmental factors. Identification of these factors may be useful in the treatment of acne in Western populations.

INTRODUCTION

ACNE AFFECTS between 40 million and 50 million individuals in the United States.¹ Although acne mainly affects adolescents, it is also present in children and adults. One study found some degree of facial acne in 54% of women and 40% of men older than 25 years.² In this same group, clinical facial acne affected 12% of the women and 3% of the men and persisted into middle age. Cunliffe and Gould³ reported similar results 20 years earlier. In pediatric populations, the prevalence of acne increases with age. In 10- to 12-year-old children, 28% to 61% of the population has clinically diagnosed acne, whereas 79% to 95% of 16- to 18-year-old adolescents are affected.^4-6 Even a significant percentage of children (aged 4-7 years) are diagnosed with acne.⁵ Thus in the Western world, acne is a ubiquitous skin disease affecting primarily adolescents but also a significant portion of adults older than 25 years.

Few studies have evaluated the prevalence of acne in nonwesternized societies. However, there is suggestive evidence in nonindustrialized societies that the incidence of acne is lower than in westernized populations. Schaefer,⁷ a general practitioner who spent almost 30 years treating Inuit (Eskimo) people as they made the transition to modern life, reported that acne was absent in the Inuit population when they were living and eating in their traditional manner, but upon acculturation, acne prevalence became similar to that in Western societies.

Prior to World War II, Okinawa was an isolated island outpost in the South China Sea, and its native inhabitants lived a rural life with few or none of the trappings of industrialized societies. Extensive medical questionnaires by US physicians administered to local physicians who had practiced from 8 to 41 years revealed that, "These people had no acne vulgaris."⁸ Dermatological examination of 9955 schoolchildren (aged 6-16 years) conducted in a rural region in Brazil found that only 2.7% of this pediatric population had acne.⁹ Dermatological examination of 2214 Peruvian adolescents by pediatricians demonstrated that acne prevalence (grades 1-4) was lower (28%) in Peruvian Indians than in mestizos (43%) or whites (45%).¹⁰

In South Africa, dermatologists found lower rates of acne among the Bantu¹¹ than among whites¹² residing in Pretoria. Bantu adolescents (aged 15-19 years; n = 510) maintained a 16% incidence rate of acne,¹¹ whereas among the white adolescents (n = 1822), the incidence was 45%.¹² For the entire sample of Bantus of all ages (n = 3905), the overall occurrence of acne was 2%,¹¹ whereas in the total white sample across all ages (n = 16 676), the incidence of acne was 10%.¹² Among the Zulu it was suggested that acne became a problem only when these people moved from rural African villages to cities.¹³ All of these studies suggest that the prevalence of acne is lower among rural, nonwesternized people than in fully modernized Western societies.

Herein we report the absence of acne in 2 nonwesternized populations: the Kitavan people living on the Trobriand Islands near Papua New Guinea and the Aché hunter-gatherers of Paraguay. Additionally, we evaluate how elements in nonwesternized environments may influence the development of acne.

Acne Vulgaris - A Disease of Western Civilization , Part 2 is HERE.