Journal Club: September 2020

Age of Menarche in a Longitudinal US Cohort

Frank M. Biro MD, Ashley Pajak MS, Mary S. Wolff PhD, Susan M. Pinney PhD, Gayle C. Windham PhD, Maida P. Galvaz MD MPH, Louise C. Greenspan MD, Larry H. Kushi ScD, Susan L. Teitelbaum PhD
J Pediatr Adolesc Gynecol 2018; 31(4): 339-345

1. How might the results of the Breast Cancer and the Environment Research Program changes recommendations for adult cancer surveillance? What findings of the study suggest a potential change in the breast cancer susceptibility window?

2. What strategies did the authors use to overcome recall bias in this study?

3. Longitudinal studies, particularly when conducted prospectively, have numerous advantages and disadvantages. Discuss the benefits and drawbacks of performing longitudinal research, including the specific biases that may arise.

4. Table 4 includes several historical studies on breast development, menarche, and imputed tempo. Study designs for these investigations were either cross-sectional or longitudinal. Discuss the differences between these two study designs. In addition, this study was a longitudinal observational study, however longitudinal research can also be repeated cross-sectional studies. Describe the differences between these methodologies. What methodology would you argue is superior for the objectives of this study?

5. There are a number of covariates that can impact the onset of menarche. As a clinician who cares for young patients entering puberty, what covariates might you expect?

6. The data is stratified by race, location and BMI%. What interactions could be present between these variables? What secondary analysis could you consider performing to evaluate for these?

7. A 7 year old patient presents to your clinic with her parents. Her mother’s family has a strong history of breast cancer and she has read this study. She knows there is a drug available which will “pause puberty.” She wants to start this medication for her child as she and her sisters and mother all had menarche at 9 and she wants to limit this one risk factor for her daughter. How would you counsel her?

8. Based on the results of this study, what advice would you give to the parents of a pre-pubertal girl with T2 breast development, regarding the timing of menarrche?