Prediction of future wrinkles for middle-aged women: A 7-year longitudinal study on the progression of wrinkles in Japanese women.

Background It is commonly believed that there is serious heterogeneity in the rate of wrinkle progression among individuals. Although several skin characteristics have been shown to influence wrinkle progression, the ability to predict which individuals with skin characteristics are likely to develop wrinkles is still limited. Objectives The purpose of this study is to develop and validate an effective prediction model for longitudinal changes in wrinkles. Methods We collected annual wrinkle scores and multiple skin physiological characteristics in 48 Japanese women over a period of 7 years. We developed a multivariable prediction model for predicting future wrinkle status based on the various skin physiological characteristics using a linear mixed-effects model. Results After variable selection by backwards, the final wrinkle prediction model included age, sebum volume, redness of skin color, lightness of skin color, and an interaction term between sebum volume and redness of skin color. The developed prediction model showed favorable prediction accuracy (R2 = 87.92%, 95% confidence interval 84.27%-90.68%). Conclusions The developed model accurately predicted levels of wrinkles in Japanese women aged 22-60 years. The prediction model is based on age and three practical skin characteristics, which might implicate an essential insight to prevent wrinkle progression in individuals.