The impact of pathological conditions on carbon and nitrogen isotopic values in the bone collagen of individuals with known biographic data and medical history

Abstract

This study aimed to refine our understanding of the extent to which chronic diseases with and without skeletal manifestation affect the isotopic values in bone collagen.Carbon and nitrogen isotopic values were measured in the ribs and femurs of 65 individuals from a documented skeletal collection (19th-21st centuries, Czech Republic). Statistically significant differences in both carbon and nitrogen isotopic values were found between particular families. There was a notable effect of the year of death on nitrogen isotopic values in ribs. Neither the presence of chronic disease in general nor the presence of carcinoma, age-related physical debility, or tuberculosis had a significant impact on isotopic values. Cases of cancer with skeletal metastases however showed an increase of 1‰-1.5‰ in nitrogen isotopic values in (i) metastasis tissue, (ii) the healthy areas of bone affected by the metastasis, and (iii) the healthy rib bone.The results demonstrate that distinct dietary habits in particular families are the main driving force affecting the isotopic values in the sampled individuals. A minor but notable temporal shift in the nitrogen isotopic values of ribs may be linked to environmental and/or societal changes during the studied period. The observed increase in the nitrogen isotopic values of individuals with bone cancer metastases is in accordance with the state of cachexia and negative nitrogen balance. Despite the low number of cases, this result urges caution, as isotopic changes to the observed degree may significantly affect the dietary interpretation of the isotopic data.

Stable isotope values of carbon and nitrogen in hair compared to bone collagen from individuals with known medical histories (Bohemia, 19th–21st centuries)

“…When considering the isotopic differences between particular families, both hair carbon and nitrogen isotopic values copied the trend previously observed in bone (Figure 1c,d; Drtikolová Kaupová et al, 2021): in the case of nitrogen isotopic values, the only sampled individual from family 1 shows the lowest δ 15 N value, individuals from families 3, 4, and 5 have intermediate δ 15 N values and families 7 and 8 show the highest δ 15 N values. As in the case of the bones, individuals Nos.…”

“…When comparing the offsets between hair and rib isotopic values (Δ hair-rib ), again there was no statistically significant difference between individuals with chronic disease and those who died suddenly (Table 2 and Figure When considering the isotopic differences between families, the limited dataset of hair samples again mirrors the pattern observed in the bone samples (Drtikolová Kaupová et al, 2021). In the case of δ 15 N values, these correspond to social status and thus the distinct standard of living in particular families.…”

“…The sample consists of 18 adult individuals (12 males, 6 females; died 1884–2006; average age‐at‐death = 70 years) with genealogical and biographical documentation. The previously published (Drtikolová Kaupová et al, 2021) rib and femur isotopic values were used to define the hair‐bone isotopic offset in this study.…”

“…The unclear impact of biological stress on bone isotopic values is one of the most important factors limiting the testimonial power of isotopic reconstruction of past diets (e.g., Reitsema, 2013). Although in recent years the corpus of bone isotopic data from medical or paleopathological cases has increased notably (for review, see Drtikolová Kaupová et al, 2021), most of the information on the mechanisms driving isotopic shifts during periods of nutritional or biological stress is still based on the examination of tissues with much more rapid turnover, most commonly hair but also nails, plasma, saliva, or urine (Reitsema, 2013; Tea et al, 2021).…”

“…This study is a follow-up to a recently published paper on bone carbon and nitrogen isotopic values, measured in the ribs and femurs of 65 individuals from a documented skeletal collection (19th-21st centuries, Czech Republic) with known medical history (Drtikolová Kaupová et al, 2021). These came mainly from rural contexts, coming from the ranks of landowners or economic managers on estates and their families, with a middle to higher middle class socio-economic status.…”