02781nas a2200253 4500008004100000022001400041245012400055210006900179260001600248520203400264100001502298700001002313700001702323700002402340700001802364700001302382700002002395700001502415700001802430700001602448700001102464700001602475856003602491 2019 eng d a1433-296500aBiochemical markers of bone turnover and risk of incident hip fracture in older women: the Cardiovascular Health Study.0 aBiochemical markers of bone turnover and risk of incident hip fr c2019 Jun 213 a

The relationships of osteocalcin (OC) and C-telopeptide of type I collagen (CTX) with long-term incidence of hip fracture were examined in 1680 post-menopausal women from a population-based study. CTX, but not OC, levels were associated with incident hip fracture in these participants, a relationship characterized by an inverted U-shape.

INTRODUCTION: We sought to investigate the relationships of OC, a marker of bone formation, and CTX, a marker of bone resorption, with long-term incidence of hip fracture in older women.

METHODS: We included 1680 women from the population-based Cardiovascular Health Study (mean [SD] age 74.5 [5.0] years). The longitudinal association of both markers with incidence of hip fracture was examined using multivariable Cox models.

RESULTS: During a median follow-up of 12.3 years, 288 incident hip fractures occurred. Linear spline analysis did not demonstrate an association between OC levels and incident hip fracture. By contrast, increasing levels of CTX up to the middle-upper range were associated with a significantly greater risk of hip fracture (HR = 1.52 per SD increment, 95% CI = 1.10-2.09), while further increases were associated with a marginally non-significant lower risk (HR = 0.80 per SD increment, 95% CI = 0.63-1.01), after full adjustment for potential confounders. In analyses of quartiles, CTX exhibited a similar inverted U-shaped relationship with incident fracture after adjustment, with a significant association observed only for the comparison of quartile 3 to quartile 1 (HR = 1.63, 95% CI = 1.10-2.43). In a subset with available measures, both OC and CTX were inversely associated with bone mineral density of the hip.

CONCLUSION: CTX, but not OC, levels were associated with incident hip fracture in post-menopausal women, a relationship characterized by an inverted U-shape. These findings highlight the complex relationship of bone turnover markers with hip fracture risk.

1 aMassera, D1 aXu, S1 aWalker, M, D1 aValderrábano, R, J1 aMukamal, K, J1 aIx, J, H1 aSiscovick, D, S1 aTracy, R P1 aRobbins, J, A1 aBiggs, M, L1 aXue, X1 aKizer, J, R uhttps://chs-nhlbi.org/node/8106