Early Life Stress and Long-Term Survival in the Hamann-Todd Collection

Objectives

The impact of physiological stress during growth and development on mortality has been a topic of intense interest in bioarchaeology and other disciplines. In this study, we analyze the association between survival and two markers of physiological stress, linear enamel hypoplasia (LEH) and adult stature, in a sample of 296 individuals from the Hamann-Todd Osteological Collection (HTOC).

Materials and Methods

The HTOC is among the most well-known osteological collections in the discipline, representing low socioeconomic status individuals from early 20th century Cleveland, Ohio. Ages-at-death and demographic identifiers (sex and socially ascribed race) were known for all individuals in the sample. The association between the skeletal and dental markers of early life stress and survival was evaluated through Kaplan–Meier survival analysis, using log rank tests to analyze the significance of differences in survival among demographic groups.

Results

Significant differences in survival were observed between demographic groups, regardless of LEH status or stature. However, there were no significant differences in survivorship by LEH presence in this sample, despite the expectation that periods of physiological stress during key stages of development contribute to long-term health consequences such as suppressed immune function. For females, shorter statures were associated with a higher probability of survival, while there were no significant differences in survival for males based on stature.

Discussion

It is likely that differences in survival observed in this sample of the HTOC are the consequence of other factors, most likely related to adult environmental quality, as opposed to early life stress.