183Observation of Bone Turnover Marker Trends and Association with Bone Protection Medications and Clinical Frailty Scale among Frail Older Adults

Abstract

Background: Bone markers [C-terminal crosslinking telopeptide of type 1 collagen (CTX-1), and procollagen type 1 N propeptide (P1NP)] are biochemical surrogates of osteoporosis which can be used to monitor response to bone protection therapies. Our aim was to determine if bone turnover markers (BTM) were different between on versus no bone protection treatment groups and explore if BTM trends correlated with Rockwood Clinical Frailty Score (CFS). Methods: Older adults admitted via the emergency department and screened positive for frailty (using PRISMA-7) were eligible for inclusion. We evaluated each patient with comprehen- sive geriatric assessment and measured serum CTX-1 and P1NP. Research ethics approved. Results: In total, 112 patients were included: 52 (46%) were prescribed bone protection medications and 60 (53%) were not. 15 (29%) were on bisphosphonates, 8 (15%) were on denosumab and 29 (56%) were on vitamin D +/- calcium supplements only. The difference in means between treatment groups for both markers was significantly different: mean CTX-1 estimate of difference 0.24, P < 0.001, mean P1NP estimate of difference 20.09, p = 0.031. We found a moderate linear relationship between BTM and CFS, which was significant for CTX-1. (Pearson’s correlation 0.32, p = 0.001) Conclusion: Our study demonstrates half of frail older adults are not prescribed bone protection. We confirm that CTX-1 and P1NP are suppressed by use of bone protection. We suggest BTM may also be correlated with CFS. Our findings represent an opportunity for the clinical application of bone markers to monitor the effect of bone protection medications, and suggest their future role as a surrogate for frailty.