The Association of Bone Turnover Markers with Muscle Function, Falls, and Frailty in Older Women in Long-Term Care

BackgroundOsteoporosis and sarcopenia commonly coexist in older adults. There is strong evidence that bone and muscle impact each other through mechanical and biochemical cross-talk.ObjectivesWe sought to investigate the relationship between the markers of bone remodeling including the C-terminal telopeptide of type 1 collagen (CTX) and procollagen type 1 N propeptide (P1NP) with muscle function, falls, and frailty in older women residing in long-term care (LTC) facilities.DesignA secondary analysis of a randomized controlled trial.SettingResidents of LTC.ParticipantsOne hundred seventy-eight older women with osteoporosis.MeasurementsWe measured and analyzed baseline CTX, P1NP, gait speed, sit to stand time, history of falls, and frailty index.ResultsParticipants had a mean age of 86.7 years and BMI of 27.6 kg/m2. The correlation (r) of CTX with gait speed and sit to stand test, as indices for muscle function, were -0.193 (p=0.0163) and 0.152 (p=0.0507), respectively. Additionally, CTX level was significantly associated with history of falls (p=0.0068), recurrent falls (p=0.0260), and frail phenotype (p=0.0126). P1NP did not have a significant association with gait speed, sit to stand test, and history of falls; however, it was associated with frail phenotype (p=0.0137). Most findings persisted after adjusting for age.ConclusionsIn older women residing in LTC facilities, CTX was associated with gait speed, falls history, and frail phenotype, whereas P1NP was only associated with frail phenotype. These findings suggest a relationship between bone remodeling and muscle function.