Risk factors for facial melasma in women: a case-control study

• Grant number: 12/13418-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2012
• End date: September 30, 2013
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Hélio Amante Miot
• Grantee: Paula Basso Lima
• Host Institution: Faculdade de Medicina (FMB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Melasma is a chronic acquired hypomelanosis, characterized by the appearance of irregular macules, symmetrical, well-defined, with a variation of light brown to grayish brown. It affects sun-exposed areas of the integument, especially the face. It affects both genders, but in a higher ratio (10:1), women between 30 and 55 years, during the menace. Is associated with a wide variety of triggering factors. The variables are well established, sun exposure, skin protection, hormonal factors, and family. But still not controlled epidemiological studies were conducted on other risk factors such as alcohol use, smoking, caffeine, use of medicines, cosmetics, ethnicity, and anxiety state. This project aims to evaluate the risk factors for the development of facial melasma in Brazilian women. In addition to describing constitutional, ethnic, family parentage, traces of anxiety, photoprotection, and sun exposure characteristics. To do so will be conducted a case-control study type, paired, involving female subjects, with adults over 18 years, voluntary, informed, and in agreement. The cases will be determined by the presence of facial melasma, clinically proven by a titled dermatologist. The controls will be defined with professionals who work on the University Campus of Unesp-Botucatu, without the presence or history of prior facial melasma. Controls will be paired with each case, according to gender and age. The main dependent variable will be the presence of facial melasma. The independent variables are grouped into hierarchical levels: constitutional and family data, sun exposure and sun protection, variables related to hormonal and anxiety traits, evaluated using the IDATE-T questionnaire. Categorical data will be represented by their percentage proportions and compared between groups using the chi-square or chi-square test for tendency. Later, will be developed a model of comparative risk between cases and controls from multiple conditional logistic regression in a hierarchical basis. Data will be tabulated in MSExcel 2007 for further analysis by software SPSS 17.0. Will be considered significant two-tailed p-value < 0.05. The sample size will be based on a pre-test with 50 cases and 50 controls and calculated for a final model of multiple logistic regression, estimated its "power" of 0.8 and a bilateral alpha level of 0.05. It is estimated 200 cases and 200 controls for project conclusion.(AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

HANDEL, A. C.; LIMA, P. B.; TONOLLI, V. M.; MIOT, L. D. B.; MIOT, H. A.. Risk factors for facial melasma in women: a case-control study. British Journal of Dermatology, v. 171, n. 3, p. 588-594, SEP 2014. (12/13418-0)