Structured additive regression modeling of age of menarche and menopause in a breast cancer screening program

Abstract

Breast cancer risk is believed to be associated with several reproductive factors, such as early menarche and late menopause. This study is based on the registries of the first time a woman enters the screening program, and presents a spatio-temporal analysis of the variables age of menarche and age of menopause along with other reproductive and socioeconomic factors. The database was provided by the Portuguese Cancer League (LPCC), a private nonprofit organization dealing with multiple issues related to oncology of which the Breast Cancer Screening Program is one of its main activities. The registry consists of 259,652 records of women who entered the screening program for the first time between 1990 and 2007 (45-69-year age group). Structured Additive Regression (STAR) models were used to explore spatial and temporal correlations with a wide range of covariates. These models are flexible enough to deal with a variety of complex datasets, allowing us to reveal possible relationships among the variables considered in this study. The analysis shows that early menarche occurs in younger women and in municipalities located in the interior of central Portugal. Women living in inland municipalities register later ages for menopause, and those born in central Portugal after 1933 show a decreasing trend in the age of menopause. Younger ages of menarche and late menopause are observed in municipalities with a higher purchasing power index. The analysis performed in this study portrays the time evolution of the age of menarche and age of menopause and their spatial characterization, adding to the identification of factors that could be of the utmost importance in future breast cancer incidence research.

Studying the relationship between a woman's reproductive lifespan and age at menarche using a Bayesian multivariate structured additive distributional regression model

“…As a final remark, this study substantiated once again the decline of the age of menarche over time, as was observed in the univariate study presented by Duarte et al (2014). The negative effect achieved on the correlation, bringing into consonance the results observed for the age at menarche and a woman's reproductive lifespan cycle separately, proves the advantage of these models when modeling the effect of the covariates in the association between a bivariate response.…”

“…In addition, the results did not capture the expected spatial effect of earlier age of menarche and wider reproductive lifespan cycles associated with the coastal regions (Rodrigues, 1993;Duarte et al, 2014), not even for the younger women cohort. In particular, older women (born before 1931) showed a nonsignificant spatial effect on the expectation and on the standard deviation of the window.…”

“…A reference to this variable is made by Nichols et al (2006), where the results pointed to an upward trend in the number of a woman's reproductive years, but in which the decreasing trend of both age at menarche and menopause found in Duarte et al (Duarte et al, 2014) does not seem to corroborate Nichols' findings. Since these two moments mark the beginning and the ending of a woman's lifetime exposure to endogenous hormones, a variable that can be taken into consideration is a woman's reproductive lifespan cycle, determined by the difference between a woman's age at menopause and menarche.…”

“…This has triggered studies aiming to analyze possible time trends regarding a woman's age at menarche and menopause (Padez and Rocha, 2003;Nichols et al, 2006;Cabanes et al, 2009;Rigon et al, 2010;Berman et al, 2012;Talma et al, 2013). This particular problem was addressed by the authors in an earlier study (Duarte et al, 2014), where they investigated how age of menarche and menopause relates to a woman's year of birth, together with other breast cancer risk factors such as whether a woman has been pregnant at least once in her life, and whether she breastfed, among others. This particular problem was addressed by the authors in an earlier study (Duarte et al, 2014), where they investigated how age of menarche and menopause relates to a woman's year of birth, together with other breast cancer risk factors such as whether a woman has been pregnant at least once in her life, and whether she breastfed, among others.…”

Association Between WRN Cys1367Arg (T>C) and Cancer Risk

“…20 Cheng found that BRCA 1452-1079 directly binds to WRN C-terminal region and subsequently lightly affects its functions. The most common polymorphisms of WRN Cys1367Arg are located in the binding domain of BRCA1.…”