Background
The Single Point Insulin Sensitivity Estimator (SPISE) index is a surrogate marker for insulin sensitivity. Given the emerging role of bone as an active endocrine organ, its associations with non-invasive measures of extra-skeletal functions such as insulin sensitivity warrant investigation.
Aims
This study aimed to explore the relationship between the SPISE index and Bone Mineral Density (BMD) in an adult population.
Methods
Data from a total of 1270 Arab adults (84% females, mean age 56.7 ± 8.1 years) from the Osteoporosis Registry Database of the Chair for Biomarkers of Chronic Diseases in King Saud University, Riyadh, Saudi Arabia was used in this study. T-scores and SPISE were calculated. Regression models were used to determine associations between SPISE and bone health indices.
Results
The low BMD group (N = 853; T-score <-1.0) had significantly higher SPISE values than those with normal BMD (N = 417; T-score − 1.0 and above) (4.6 ± 1.3 vs. 4.3 ± 1.2, p < 0.001). Multivariate linear regression, adjusted for covariates, confirmed a significant inverse association between SPISE and BMD for all participants (β=-0.22, p < 0.001), as well as both groups [normal BMD (β = -0.10, p = 0.02) and low BMD groups (β = -0.15, p < 0.001)]. SPISE, family history of T2DM, and history of fractures collectively account for 17% of the variances perceived in T-score for all participants (p < 0.001).
Conclusions
A significant inverse association between the SPISE index and BMD was observed in adults, suggesting a link between BMD and extra-skeletal health. Underlying mechanisms need to be investigated prospectively using BMD as secondary outcomes in lifestyle modification programs.