Environmental factors may interact with different genetic backgrounds to impact skin aging. In this study, we (i) compared ethnic differences in skin aging between Chinese and German women and (ii) explored environmental factors in both populations. Chinese and German women 65-90 years old were recruited and skin aging was assessed by the SCINEXATM. In adjusted regression analysis, we found that wrinkles under eyes (p<0.001), on upper lips (p=0.001) as well as laxity of eyelids (p=0.025) and cheeks (p<0.001) were more pronounced in Germans; while wrinkles on forehead (p<0.001) and nasolabial folds (p=0.002) were more pronounced in Chinese. Chinese showed larger pigment spots on forehead (p<0.001) and on cheeks (p<0.001); while Germans had larger number of pigment spots on arms (p<0.001) and hands (p=0.001). Skin aging signs were affected by environmental factors: sun exposure, smoking, alcohol consumption, education, pregnancy, use of contraception, and use of fossil fuels. Sun exposure had a more significant effect in Germans, affecting 12 skin aging signs, particularly signs related to pigment spots. In Chinese, indoor air pollution from cooking had a greater effect, affecting 7 skin aging signs. Cooking with fossil fuels primarily affected wrinkle related signs, including wrinkles on forehead (p<0.001), in the crow’s feet area (p=0.001), on upper lip (p<0.036) and nasolabial fold (p<0.001) as well as laxity of eyelids (p=0.007), laxity of cheeks (p=0.019) and fine wrinkles on hands (p=0.027). Our results confirm previous published findings that air pollution accelerates the appearance of skin aging symptoms. They also suggest that clinical manifestations of skin aging are modified by the type of pollution (indoor versus outdoor) as well as the ethnic background (Chinese versus Caucasian), indicating the existence of gene/environment interactions.
Environmental factors may interact with different genetic backgrounds to impact skin aging. In this study, we (i) compared ethnic differences in skin aging between Chinese and German women and (ii) explored environmental factors in both populations. Chinese and German women 65-90 years old were recruited and skin aging was assessed by the SCINEXATM. In adjusted regression analysis, we found that wrinkles under eyes (p<0.001), on upper lips (p=0.001) as well as laxity of eyelids (p=0.025) and cheeks (p<0.001) were more pronounced in Germans; while wrinkles on forehead (p<0.001) and nasolabial folds (p=0.002) were more pronounced in Chinese. Chinese showed larger pigment spots on forehead (p<0.001) and on cheeks (p<0.001); while Germans had larger number of pigment spots on arms (p<0.001) and hands (p=0.001). Skin aging signs were affected by environmental factors: sun exposure, smoking, alcohol consumption, education, pregnancy, use of contraception, and use of fossil fuels. Sun exposure had a more significant effect in Germans, affecting 12 skin aging signs, particularly signs related to pigment spots. In Chinese, indoor air pollution from cooking had a greater effect, affecting 7 skin aging signs. Cooking with fossil fuels primarily affected wrinkle related signs, including wrinkles on forehead (p<0.001), in the crow’s feet area (p=0.001), on upper lip (p<0.036) and nasolabial fold (p<0.001) as well as laxity of eyelids (p=0.007), laxity of cheeks (p=0.019) and fine wrinkles on hands (p=0.027). Our results confirm previous published findings that air pollution accelerates the appearance of skin aging symptoms. They also suggest that clinical manifestations of skin aging are modified by the type of pollution (indoor versus outdoor) as well as the ethnic background (Chinese versus Caucasian), indicating the existence of gene/environment interactions.