Abstract
Purpose
Early age at menarche (AAM) has been associated with increased mortality and morbidity, including premature death from all causes, breast cancer and cardiovascular diseases. The aim of this study was to examine the association between AAM and all-cause mortality.
Subjects and methods
A total of 12,409 women aged 25–94 years who took part in the fourth Tromsø Study in Norway during 1994–1995 were included in this prospective population-based study with a mean 18.7 years of follow-up. Multivariate Cox proportional hazard analysis was used to investigate the association between AAM and all-cause mortality with adjustment for known confounders (age, body mass index, physical activity, level of education and smoking history).
Results
During the 18.7 years of follow-up, a total of 2,203 women died. There was no association between AAM and all-cause mortality before or after adjusting for possible confounding factors.
Conclusion
This prospective study of 12,409 women did not find any association between AAM and all-cause mortality
Acknowledgments
This particular research project did not receive any specific funding. The Tromsø Study as a cohort has since 1974 been supported by a number of institutions and funding agencies, mostly the University of Tromsø, now UiT The Arctic University of Norway, but also the Northern Norway Regional Health Authority Medical Program, and supported by grants from the Norwegian Research Council, among others. The administration of the questionnaires with questions about AAM was conducted by the National Health Screening Services, Oslo, Norway. No funding body had any role in the design of the study and collection, analysis and interpretation of data and in writing the manuscript.
Author contributions
MWL conducted most of the statistical analyses and drafted the manuscript. BKJ suggested the topic for research, conducted some of the analyses, and contributed to the study’s analytical strategy. Both authors took part in the revision of the drafted manuscript for intellectual content, have read and approved the final manuscript, and agree to be accountable for all aspects of the work.
Disclosure
The authors report no conflicts of interest in this work.