Association Between Bone Mineral Density and Pancreatic β-Cell Function in Elderly Men and Postmenopausal Women

Purpose: To explore the association between bone mineral density (BMD) and β-cell function. Methods: A cross-sectional study was performed in Fujian, China, from 2011 to 2012. The study included 572 elderly men older than age 60 years and 1558 postmenopausal women aged 45 to 86 years, excluding those with diabetes and insulin resistance. Fasting glucose and insulin concentrations were measured. Pancreatic β-cell function was estimated by using the homeostasis model assessment (HOMA-β). Calcaneus BMD was measured by using quantitative ultrasonography. Multiple regression analyses were applied to explore the association. Results: Participants with decreased BMD had lower fasting glucose (P < 0.001 in postmenopausal women; P = 0.007 in elderly men) and greater HOMA-β (P = 0.001 in postmenopausal women; P = 0.008 in elderly men) than those with normal BMD, whereas no statistical differences in insulin were seen among categories of BMD. After adjustment for all confounders, HOMA-β was still significantly negatively related to BMD in both groups (all P < 0.001), and remarkable positive relationships were found between BMD and fasting glucose. Furthermore, binary logistic regression presented fully adjusted odds ratios for diabetes in those with osteoporosis vs those with normal BMD: 0.60 [95% confidence interval (CI), 0.38 to 0.94] and 0.66 (95% CI, 0.49 to 0.91) in the original selected population of elderly men (n = 1070) and postmenopausal women (n = 2825), respectively. Conclusions: BMD was independently inversely associated with HOMA-β and positively associated with fasting glucose in both elderly men and postmenopausal women, suggesting that bone mass may be a predictor of glucose metabolism. Further research is needed to verify the associations and determine the exact mechanism underlying them.