Extrinsic skin ageing in German, Chinese and Japanese women manifests differently in all three groups depending on ethnic background, age and anatomical site.
BACKGROUND
It has been suggested that extrinsic skin ageing manifests differently in Caucasians versus East Asians. In particular, from previous studies it was concluded that Caucasians are more prone to develop wrinkles, whereas pigment spot formation is the hallmark of extrinsic skin ageing in East Asians. However, these assumptions are based on a very limited number of studies which did not include different East Asian populations.


OBJECTIVE
We here compare the manifestation of extrinsic skin ageing signs in German, Japanese and Chinese women by specifically elucidating the age and anatomical site dependence of any potential ethnic difference.


METHODS
In the present study, we assessed skin ageing in N=902 German, N=165 Japanese and N=1260 Chinese women ranging from 30 to 90 years by means of SCINEXA™. Linear regression analysis was used to test for ethnic differences and their age and site dependence adjusted for educational level, sun exposure, smoking and sun protection behaviours.


RESULTS
Pigment spots and wrinkles on the face were present among all three ethnic groups and differences were influenced by age and anatomical sites independently of further influencing factors. Pigment spots on the forehead were most pronounced over the whole age range in Chinese and German women and least developed in Japanese. Pigment spots on cheeks were a typical extrinsic skin an ageing sign in the two East Asian populations in all age groups. However, in older German women they reach the same level as observed in the two East Asian populations. In contrast, pigment spots on arms and hands were significantly more pronounced in German women ≥45years of age. Wrinkles were not exclusively a skin an ageing sign of German women, but were also very pronounced in Chinese women on forehead, between the eyebrows and in the crow's feet area.


CONCLUSIONS
These results corroborate the previous notion that the occurrence of pigments spots and wrinkles is different between Caucasians and East Asians. In addition, this study shows that this difference depends on age and anatomical site and that it also differs between different ethnic groups from East Asia.
IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.
Andrea
A
Vierkötter
IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.
Anke
A
Hüls
Department of Geriatric and Environmental Dermatology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Ai
A
Yamamoto
IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.
Sabine
S
Stolz
IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.
Ursula
U
Krämer
The Estee Lauder Companies Inc, Melville, NY, United States.
Mary S
MS
Matsui
Department of Geriatric and Environmental Dermatology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Akimichi
A
Morita
Chinese Academy of Sciences Key Laboratory of Computational Biology, Chinese Academy of Sciences - Max Planck Partner Institute for Computational Biology, Shanghai Institutes of Biological Sciences, Shanghai, China; China Medical City Institute of Health Sciences, Taizhou, China; Minister of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai, China.
Sijia
S
Wang
Institute of Reproductive & Child Health/Ministry of Health Key Laboratory of Reproductive and Child Health, School of Public Health, Peking University, Beijing, China.
Zhiwen
Z
Li
Chinese Academy of Sciences Key Laboratory of Computational Biology, Chinese Academy of Sciences - Max Planck Partner Institute for Computational Biology, Shanghai Institutes of Biological Sciences, Shanghai, China; China Medical City Institute of Health Sciences, Taizhou, China; Minister of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai, China.
Li
L
Jin
IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany. Electronic address: Jean.Krutmann@iuf-duesseldorf.de.
Jean
J
Krutmann
IUF-Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.
Tamara
T
Schikowski
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D002681:China; D005260:Female; D005858:Germany; D006801:Humans; D017495:Hyperpigmentation / Q000175:diagnosis / Q000208:ethnology*; D007564:Japan; D016014:Linear Models; D008875:Middle Aged; D012737:Sex Factors; D015595:Skin Aging / Q000208:ethnology*; D012880:Skin Pigmentation; D044465:White People
Age dependence; Anatomical site dependence; Ethnic populations; Extrinsic skin ageing