The critical and sensitive periods model, a key component of the life course health and development (LCHD) framework, describes windows of growth, development, or change during which exposures can permanently affect the structure or function of the body and influence its trajectories for health. Research on critical and sensitive periods has traditionally focused on the impact of early life influences on later life health. This focus on infancy and youth is due to the rapid pace at which development and growth occurs, which can make individuals particularly susceptible to the influences of risk and protective factors.
Perimenopause—the transition period bridging women’s reproductive and post-reproductive years—is another window, however, in which rapid physiological changes occur, yet minimal research has investigated this time as a critical or sensitive period. The three papers included in this dissertation investigate the health of women at mid-life and explores how their experiences during the menopausal transition affect their chronic disease risk and longevity.
The first paper, a scoping review, compares the physiological similarities between perimenopause and puberty and their respective associations with some of the most prevalent chronic conditions in the United States. The second paper, a longitudinal cohort analysis of women undergoing the menopausal transition, explores whether perimenopause represents a sensitive window for stress responsivity. Using survey data from the Study of Women’s Health Across the Nation (SWAN), a national study of 3,300 women at midlife, the relation between psychological stress, perimenopause, and fibrinogen—a biomarker for systemic inflammation—is examined. The third paper, a time series analysis of population cohorts in France and England in Wales during the 19th Century, tests whether the age range at which perimenopause occurs at the population level is a sensitive window for longevity. The relation between cohort mortality at ages 45-49 and life expectancy at age 60, specifically, is examined using data from the Human Mortality Database.
The primary findings from these three papers are as follows: 1) Perimenopause shares many physiological similarities with puberty, a well-documented sensitive window for a number of health outcomes. The interaction of certain behaviors or exposures with the significant hormonal shifts during perimenopause, moreover, appears associated with risk for mood disorders, metabolic-related morbidities, autoimmune diseases, cardiovascular disease, cancer, musculoskeletal disorders, and premature mortality. 2) Women’s perceptions of stress appear to change during the course of the menopausal transition; however, such changes are not associated with adverse physiological effects, as measured through changes in fibrinogen. 3) Adverse environmental conditions during perimenopause appear significantly related to decreased longevity among women in France and England and Wales during the 19th Century.
