Relationships between obesity markers and bone parameters in community-dwelling older adults

Background Osteoporosis is an age-related condition that can lead to fragility fractures and other serious consequences. The literature data on the impact of obesity on bone health are contradictory. The main reasons for this discrepancy could be the imperfect nature of the body mass index (BMI) as a marker of obesity, the metabolic status (inflammation and metabolically healthy obesity), and/or heterogeneity in bone variables and architecture or sex. Aims To examine the relationship between bone variables and three validated obesity criteria. Methods In this cross-sectional study, participants were classified as obese according to their BMI, waist circumference (WC), and fat mass (FM). Bone variables and architecture were assessed using dual-energy X-ray absorptiometry and peripheral quantitative computed tomography, respectively. Results One hundred sixty-eight adults aged 55 or over (men: 68%) were included. 48 (28%) participants were obese according to the BMI, with 108 (64%) according to the FM, and 146 (87%) according to the WC. Bone variables were positively correlated with WC and BMI (Pearson’s r = 0.2–0.42). In men only, the obesity measures were negatively correlated with cortical bone density (Pearson’s r = − 0.32 to − 0.19) and positively correlated with cortical bone area (Pearson’s r = 0.22–0.39). Conclusion Our findings indicate that independent of sex and obesity criteria, when significant, being obese seems to lead to higher bone parameters than being non-obese, except for cortical bone density. Thus, in the obese population, assessing cortical density might help the physician to identify bone alteration. Further researches are needed to confirm our findings.