Quantifying Age-Related Bone Loss and Vitamin D Deficiency: Exploring Co-Occurrence and Co-Morbidity in Two 18th to 19th Century French-Canadian Communities

Abstract

This study analyzed age and sex-related bone quantity and quality patterns in the historical French-Canadian communities of Pointe-aux-Trembles and Sainte-Marie-de-Beauce. The analyses were undertaken using newly developed techniques in metacarpal radiogrammetry and rib micro-CT assessment. The patterns of bone quantity and quality were used to infer biological and social contributions to individual and community health in the past. Second metacarpals from a sample of 43 individuals from Pointe-aux-Trembles (f=12, m=6) and Sainte-Marie (f=15, m=10) were radiographed and assessed. A 1.9cm region of interest (ROI) was isolated on the diaphyseal surface. Within this ROI, cortical and total bone areas were measured and used to calculate the cortical area index (CAROI). Patterns of bone amount by age category (15-29, 30-49, 50+) and sex were statistically analyzed. There were no statistically significant differences in CAIROI between males and females, and no significant differences were found between any of the age categories. From the total sample of 43 individuals, rib fragments from a sub-sample of 10 individuals were chosen for micro-CT analysis. Five micro-CT slices along a 1cm segment of bone were examined and assigned scores for the appearance of mineralization defects associated with osteomalacia. Scores obtained were examined alongside the age, sex, and CAIROI data. Seven individuals in this sub-sample showed consistent evidence of mineralization defects throughout their ribs, although no patterns were noted between the presence and severity of defects and age, sex, or CAIROI. These results highlight the bioculturally complex nature of individual and community health in the past. Pointe-aux-Trembles and Sainte-Marie both experienced frequent periods of starvation, the spread of infectious disease from urban centers, and a potential lack of vitamins necessary to develop good-quality bone in adequate amounts. Analyzing these results alongside historical context provided insight into the long-term impacts of stress events on individual and community health.