Epidemiological Study Of Acne Among College Students In China And Epidermal Biophysical Properties Of Females During Four Seasons In Kunming,China

The first part:Epidemiological study of acne among college students in ChinaObjective(s):To determine the prevalence among college students in China and evaluate the risk factors of acne by epidemiological study.Methods:From September to October 2018,we conducted a cross-sectional university-based survey in representative samples among college students in 29 provinces of China(n=23489),identified by a stratified sampling method.A structured questionnaire survey(Appendix 1)was conducted via face-to-face interviews between investigators(dermatologists)and respondent(college students),to obtain sociodemographic information,family history,living habits(e.g.dietary habits,sleep quality,attitude of sun protection),body mass index(BMI)=height(kg)/weight2(m2),patient health questionnaire-9(PHQ-9),skin type and clinical scale.We summarized variables for the groups of colleges with and without acne by using descriptive statistics.And we used wald chi-square test,rank-sum test and logistic regression analysis to identify potential risk factors for acne.Results:1.Prevalence of acne among college students in China:The overall prevalence of acne was 45.22%among colleges students,45.21%for males and 45.22%for females,and there was no statistical difference between male and female(P>0.05)Population with acne included 58.63%for grade ?(mild),31.13%for grade ?(moderate),7.92%for grade ?(moderately severe),2.32%for grade ?(severe).The prevalence of acne was 67.67%in north China,36.23%in northeast China,43.36%in east China,33,85%in central China,55.51%in south China,53.62%in southwest China,and 46.43%in northwest China,there was a statistical difference in the prevalence of acne in each region(P<0.001).2.Influencing factors of acne among college students in China:On multivariate logistic regression analysis,family history of acne was associated with an increased probability of having acne(OR 3.498,95%CI 3.205 to 3.819,P<0.001,for both first-and second relatives with acne vs.without family history),as were the consumption of greasy food(OR 1.203,95%CI 1.078 to 1.343,for eating much vs.eating little,P<0.001),dairy food(OR 1.206,95%CI 1.098 to 1.326,,P=0.001)and overheated/hot food(OR 1.115,95%CI 1.014 to 1.227,P=0.014).Overweight and obesity(OR 1.225,95%CI 1.103 to 1.361,OR 1.270,95%CI 1.008 to 1.600,P<0.001),oil skin(OR 7.247,95%CI 6.582 to 7.978,P<0.001),mixed skin(OR 3.614,95%CI 3.284 to 3.976,P<0.001),dry skin(OR 1.477,95%CI 1.306 to 1.670,P<0.001),poor sleep quality(OR 1.315,95%CI 1.155 to 1.497,P<0.001),not paying attention to sun protection(OR 1.068.95%CI 1.003 to 1.138,P=0.039)were associated with an increased probability of acne.Having suitable sea food(OR 0.792,95%CI 0.721 to 0.869,P<0.001),good measure of anti-PM2.5(OR 0.841,95%CI 0.732 to 0.966,P=3.009)were protective factors.3.PHQ-9 of college students:Students with acne had a higher rate of depressive symptoms than students without acne(58.20%vs.41.80%,Z=-11.60,P<0.001).4.Proportion of college students with sensitive skin:Students with acne had a higher incidence of sensitive skin than those without acne(60.35%vs.39.65%,?~2=612.0,P<0.001).Conclusion(s):1.The overall prevalence of s acne was 45.22%among college students of China,mostly mild to moderate acne according to clinical features.2.Family history,overweight and obesity,greasy food,dairy food,overheated/hot food,oil skin,mixed skin,poor sleep quality and not paying attention sun protection were risk factor for acne.3.Having suitable sea food and good measure of anti-PM2.5 were protective factors.4.Students with acne have a higher risk of depressive symptoms than those without acne.5.Students with acne had a higher incidence of sensitive skin than those without acne.The Second part:Epidermal biophysical properties of females during four seasons in Kunming,ChinaObjective(s):To assess seasonal variation of epidermal biophysical properties in spring,summer,autumn and winter of healthy women in Kunming,China by using noninvasive test methods.Methods:From July 2018 to March 2019,a total of 72 women,aged 19-28 years,were enrolled in this study.Transepidermal water loss rates(TEWL),stratum corneum(SC)hydration,sebum content,melanin index(MI),erythema index(EI)and L*a*values were measured on the right cheek and the right forearm,using a non-invasive skin physiological instrument in the spring,summer,autumn and winter in Kunming,China.One-way analysis of variance(ANOVA)and least-significant difference t-test(LSD t-test)were used to compare the difference of the biophysical parameters in four seasons.Results:On the cheek,TEWL,SC hydration,sebum,MI and L*a*values varied greatly with seasons(P<0.05).SC hydration,sebum,MI,a*value peaked in the summer,but went lowest in winter.In contrast,TEWL and L*value went lowest in summer but peaked in winter.Similarly,SC hydration,MI and L*value also varied with seasons on the forearm(P<0.05).In addition,SC hydration,sebum,MI,EI and a*value of the cheek were higher than that of the forearm(P<0.001),but L*values of the cheek were lower than that of the forearm(P<0.001).There were no correlations among TEWL and MI,EI,L*a*values in any season(P>0.05).Conclusion(s):Both epidermal permeability barrier function,sebum and skin pigment in healthy women vary with seasons in Kunming,China.In summer,epidermal permeability barrier function is the best,sebum is the most,skin pigment is the highest,and in winter is the opposite.