The relationship between cause of death and skeletal markers of physiological stress in the Hamann-Todd collection

Objectives: Socioeconomic status, past stress events, and other factors may contribute to the cumulative burden of physiological stress, which influences an individual's susceptibility to mortality and cause of death (COD). Here, we explore the association between skeletal evidence of stress and COD in the Hamann-Todd Osteological Collection (HTOC), a predominantly low socioeconomic status sample from the late 19th and early 20th century.

Materials and methods: Skeletal markers of stress including linear enamel hypoplasia (LEH), stature, and antemortem tooth loss (AMTL) were analyzed in 298 individuals in the HTOC. Recorded CODs were grouped into six broad categories and contrasted with stress indicators, ages-at-death, and demographic variables, using various parametric and non-parametric statistical tests.

Results: COD varied by socially ascribed race and sex within the sample. Overall, infectious diseases were more prevalent than degenerative diseases. Individuals that died of infectious diseases had significantly lower ages-at-death compared to degenerative diseases (p < 0.001). There was no association between LEH and COD (χ² = 4.449, p = 0.487). Stature varied significantly across COD categories for males (F = 2.534, p = 0.032), but not females (F = 1.733, p = 0.132). Controlling for age-at-death, AMTL prevalence was associated with COD (H = 18.53, p = 0.002), with cardiovascular disease being associated with higher prevalence of AMTL.

Discussion: These findings show that some skeletal stress indicators are associated with COD in the HTOC, but the causal pathways of these relationships are not clear. This study adds to growing bodies of literature exploring relationships between past stress events and susceptibility to mortality and long-term consequences of poor living conditions for past individuals.