Article in the Spotlight

Each month the Levy Library showcases the achievements of Mount Sinai faculty and researchers by highlighting an article and its altmetrics. Altmetrics are alternative measures of impact that capture non-traditional data like abstract views, article downloads, and social media activity.

This month we highlight an article written by a team of researchers including Mount Sinai’s Dr. Maida Galvez, MD, Associate Professor in the Departments of Environmental Medicine & Public Health and Pediatrics; Dr. Susan Teitelbaum, PhD, Research Professor in the Department Environmental Medicine & Public Health; and Dr. Mary Wolff, PhD, Professor in the Departments of Environmental Medicine & Public Health and Oncological Sciences.

Citation: Biro FM, Greenspan LC, Galvez MP, et al. Onset of breast development in a longitudinal cohort. Pediatrics. 2013;132(6):1019-1027.

 

Summary: 

This study examined age at onset of breast development (thelarche), and the impact of BMI and race/ethnicity, in the 3 puberty study sites of the Breast Cancer and the Environment Research Program, a prospective cohort of over 1,200 girls (6-8 year olds) in 3 geographic areas. Researchers observed the onset of thelarche at younger ages than previously documented, with important differences associated with race/ethnicity and BMI, confirming and extending patterns seen previously.

Full Abstract:

Background and objectives: There is growing evidence of pubertal maturation occurring at earlier ages, with many studies based on cross-sectional observations. This study examined age at onset of breast development (thelarche), and the impact of BMI and race/ethnicity, in the 3 puberty study sites of the Breast Cancer and the Environment Research Program, a prospective cohort of >1200 girls.

Methods: Girls, 6 to 8 years at enrollment, were followed longitudinally at regular intervals from 2004 to 2011 in 3 geographic areas: the San Francisco Bay Area, Greater Cincinnati, and New York City. Sexual maturity assessment using Tanner staging was conducted by using standardized observation and palpation methods by trained and certified staff. Kaplan-Meier analyses were used to describe age at onset of breast maturation by covariates.

Results: The age at onset of breast stage 2 varied by race/ethnicity, BMI at baseline, and site. Median age at onset of breast stage 2 was 8.8, 9.3, 9.7, and 9.7 years for African American, Hispanic, white non-Hispanic, and Asian participants, respectively. Girls with greater BMI reached breast stage 2 at younger ages. Age-specific and standardized prevalence of breast maturation was contrasted to observations in 2 large cross-sectional studies conducted 10 to 20 years earlier (Pediatric Research in Office Settings and National Health and Nutrition Examination Survey III) and found to have occurred earlier among white, non-Hispanic, but not African American girls.

Conclusions: We observed the onset of thelarche at younger ages than previously documented, with important differences associated with race/ethnicity and BMI, confirming and extending patterns seen previously. These findings are consistent with temporal changes in BMI.

View the article on Plum X 

View Dr. Galvez’s profile on Plum X 

View Dr. Teitelbaum’s profile on Plum X 

View Dr. Wolff’s profile on Plum X