Frailty or resilience? Hazard-based and cumulative phenotype approaches to discerning signals of health inequality in medieval London.

Bioarchaeology uses human skeletal remains to reconstruct varied experiences of individuals and populations in the past, including patterns of health across time periods and cultural contexts. In the past three decades, bioarchaeological studies have highlighted the concept of "frailty," operationalizing it as increased risk of mortality or cumulative phenotypes. Using data from medieval London cemeteries, we integrate these two approaches to frailty in past populations. First, we estimate the risks of mortality and survivorship (hazard and survival analyses) associated with 10 biomarkers and use these results to construct population-specific frailty and resilience indices. Then, we apply the indices to adult individuals to explore frailty and resilience differentials between males and females in medieval London. Findings suggest that the male-female morbidity-mortality paradox observed in modern populations may not have existed in this context, which may be explained by preferential cultural buffering of men in this patriarchal, urban setting.