Molly Fox

University of California Irvine

 

In order to determine what Alzheimer’s Disease (AD) risk may have been in pre-modern human populations, it is necessary to identify how modifiers of AD risk have changed across human history. A major difference between modern and pre-modern human populations is in the amount of time a woman spends pregnant and lactating. Does this change have implications for AD risk today compared to the past? Previous studies have investigated how a woman’s reproductive history affects her AD risk, but these studies have been limited by their exclusive focus on the role estrogens. In fact, female reproductive physiology is involved in several different pathways implicated in AD etiology. Here, I focus on the role of the acquired immune system in mediating female reproductive physiology’s effects on AD etiology. In a case-control cross-sectional study of elderly British women, I use Cox proportional-hazards modeling to measure how women’s pregnancy and lactation histories modify AD risk. Results suggest that having had more pregnancies is associated with lower AD risk, and having breastfed for longer may have differential effects based on inflammatory predisposition. These results have implications for discerning what AD rates may have been in pre-modern populations via differences in reproductive life-history norms.