Assessment of Predictors of Sun Sensitivity as Defined by Fitzpatrick Skin Phototype in an Ecuadorian Population and Its Correlation with Skin Damage.

BACKGROUND: The Fitzpatrick skin phototype scale (FSPTS) is a widely used instrument to assess skin type. METHODS: A cross-sectional survey collected responses from 254 subjects from Quito regarding self-reported FSPTS, gender, age, education, and tobacco and alcohol consumption. Univariate and multivariate logistic regression analyses were performed to determine if ethnicity, hair color, and eye color significantly predict FSPTS. In addition, we studied the correlation between FSPTS and the SCINEXA scale with Pearson's correlation coefficient. RESULTS: Ethnicity, eye color, and hair color are significant independent predictors of FSPTS (p < 0.0001). CONCLUSIONS: Patient self-reported race and pigmentary phenotypes are inaccurate predictors of sun sensitivity as defined by Fitzpatrick skin phototype. Our study does not fully represent the population of the country. There are limitations to using patient-reported race and appearance in predicting individual sunburn risk.

Exploratory study of the reproducibility of the SCore for INtrinsic and EXtrinsic skin aging (SCINEXA) scale in "Ruta Escondida de la Mitad del Mundo", Ecuador, 2017.

BACKGROUND: Few studies have been published related to the analysis of different skin aging parameters for whole-body skin using the SCINEXA scale for skin damage. The aim of this study was to evaluate the reproducibility of the SCINEXA scale (SCore for INtrinsic and EXtrinsic skin Aging) in South-Americans non-Caucasian population of a region of Ecuador. METHODS: Exploratory observational study. Thirty subjects of both genders, over 40 years old and living in a rural area with particular characteristics regarding sun exposure were included. The SCINEXA scale was applied at three different time points to assess its reproducibility. Repeated measures analysis of variance was used for comparison of mean SCINEXA scores. Intraclass correlation coefficient, 95% CI and "Cronbach's alpha" coefficient were performed to measure reproducibility. RESULTS: Among participants, 86.7% were female; mean age was over 67 years old, with mainly low educational level, and almost half had more than six hours of sun exposure per day. Test-retest reproducibility of this scale demonstrated almost perfect agreement. The SCINEXA score was greater than 2 points in half of the subjects, reflecting aging due to sun exposure. LIMITATIONS: Most participants were women from one town in a particular geographical area, and the sample size was small. Genetic determinants of skin phenotypes were not assessed. CONCLUSIONS: The SCINEXA score is reproducible in South American non-Caucasian subjects of a particular region of the country. Damage from sun exposure was evident in participants.