Investigation On Skin Barrier Function Of Healthy Population In Seven Cities Of China

Objectives:To evaluate and compare the differences in skin barrier function between healthy people in different areas of China through noninvasive test methods for epidermal barrier function,and to explore the correlations between the humidity,temperature,sunshine and skin barrier function.Methods:A total of 1686 healthy volunteers coming from Beijing,Kunming,Quanzhou,Hangzhou,Wuhan,Xi’an and Chengdu participated in the study.The stratum corneum hydration,the trans-epidermal water loss(TEWL)and sebum content were measured on middle forehead and right cheek by the noninvasive measurements.The Kruskal-Wallis H test and the Nemenyi test were used to compare the stratum corneum hydration,TEWL value and sebum in the healthy volunteers from the seven cities.Then the climate factors including temperature,humidity and sunshine were compared by one-way ANOVA.And the correlation between those climatic factors and skin barrier function was analyzed by Spearman correlation.Results:1.Comparison of skin barrier function between seven cities1.1 In the seven cities,there were significant differences in SCH,TEWL value and Seb between the central and right cheek(P<0.05).The SCH of forehead(47.6 ± 16.4)and right cheek(43.9±24.8)from the volunteers in Beijing were the lowest in the seven cities.The TEWL value of forehead(7.7±4.3 g/h·cm2)and right cheek(6.0±3.0g/h·cm2)from the volunteers in Xi’an were the lowest in the seven cities.The Seb of forehead(7.5±9.3μg/cm2)and right cheek(3.5±7.5μg/cm2)from the volunteers in Xi’an were the lowest in the seven cities.1.2 Using the Nemenyi test to compare the differences between the seven cities’ skin barrier function.1.2.1 Comparing the SCH of forehead in the seven cities,Cherngdu,Quanzhou,Hangzhou,Kunming,Wuhan and Quanzhou except Xi’an,were significantly higher than that in Beijing,and the difference was statistically significant(P<0.05).1.2.2 Comparing the TEWL value of forehead in the seven cities,Quanzhou,Wuhan,Beijing,Kunming and Hangzhou except Chengdu,were significantly higher than that in Xi’an,and the difference was statistically significant(P<0.05).1.2.3 Comparing the Seb of forehead in the seven cities,Quanzhou,Hangzhou,Chengdu,Kunming,Beijing and Wuhan were significantly higher than that in Xi’an,and the difference was statistically significant(P<0.05).1.2.4 Comparing the SCH of cheek in the seven cities,Chengdu,Quanzhou,Kunming,Hangzhou,Wuhan and Xi’an were significantly higher than that in Beijing,and the difference was statistically significant(P<0.05).1.2.5 Comparing the TEWL value of cheek in the seven cities,Quanzhou,Wuhan,Beijing,Kunming,Chengdu and Hangzhou were significantly higher than that in Xi’an,the difference was statistically significant(P<0.05).1.2.6 Comparing the Seb of cheek in the seven cities,Quanzhou,Hangzhou,Chengdu,Kunming,Wuhan and Beijing were significantly higher than that in Xi’an,the difference was statistically significant(P<0.05).2.Comparison of meteorological data between seven citiesThere were significant differences in the average relative humidity,the average monthly temperature,monthly average minimum temperature,monthly average maximum temperature,and monthly mean sunshine time between the seven cities by one-way ANOVA(P<0.05).In seven cities,the average relative humidity of Wuhan(83.0%)was the highest,and the lowest was in Beijing(60.0%);the average temperature of Quanzhou(23.6℃)was the highest,and the lowest was in Beijing(13.5℃);the longest average sunshine time city was Beijing(177.7h),but Chengdu(49.8h)was the shortest one.3.Correlation between meteorological data and SCH,TEWL and SebUsing Spearman correlation analysis,there was a positive correlation between the average relative humidity and the SCH of forehead and cheek.But the TEWL value and Seb of the forehead and the Seb of the cheek were negatively correlated with the mean relative humidity.The SCH,TEWL value and Seb were positively correlated with monthly mean temperature,minimum monthly temperature and maximum monthly temperature.There was a strong correlation between the Seb and them.There was a negative correlation between the SCH of the forehead and the average sunshine time;and the amount of TEWL and sebum were positively correlated with the average sunshine time(P<0.05).Conclusions:There were significant differences in the SCH,TEWL value,and Seb in the healthy volunteers from the seven cities,which indicated that the skin barrier function was different in the seven cities.There were relationships between the climatic factors including humidity,temperature and sunshine time and the SCH,the TEWL value and the Seb,indicating that climate was an important factor affecting the skin barrier function between different cities.