Abstract: Objective To investigate the relationship between bone markers and coronary artery calcification (CAC) in patients on maintenance hemodialysis (MHD), and to explore the influencing factors for bone markers in these patients.  Methods  A total of 88 MHD patients treated in Wenzhou People's Hospital were recruited. They were divided into CAC group (n=59) and non-CAC group (n=29) based on the CAC score. General clinical data, biochemical results including the inflammation indicators of serum amyloid A protein (SAA), high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6), and the bone markers of alkaline phosphatase (ALP), N-terminal osteocalcin (N-MID), type 1 collagen cross-linking β-C terminal peptide (β-CTX) and procollagen type 1 N-terminal propeptide (PINP) were recorded. These biochemical parameters were compared between the two groups to evaluate the relationship between bone markers and CAC and the risk factors for CAC.  Results  ①The bone markers were higher in CAC group than in non-CAC group [N-MID: 174.34±88.44 vs. 120.59±76.32, t=2.182, P=0.034; β-CTX: 2.58±0.99 vs. 1.74±1.0, t=2.912, P=0.005; ALP: 95 (59.0~489.00) vs. 83.5 (47.0~129.0), t=2.480, P=0.017], suggesting the presence of higher turnover osteopathy in CAC group.  ②Correlation analyses found that PINP was positively correlated with the inflammation indicators of hs-CRP (r=0.438, P=0.001), IL-6 (r=0.357, P=0.028) and SAA (r=0.298, P=0.038); parathyroid hormone (PTH) was positively correlated with β-CTX (r=0.588, P=0.000), N-MID (r=0.463, P=0.001), PINP (r=0.369, P=0.007), and PINP/β-CTX (r=0.364, P=0.009); β2-microglobulin (β2-MG) was positively correlated with N-MID (r=0.389, P=0.005), PINP (r=0.360, P＜0.010) and PINP/β-CTX (r=0.383, P=0.006); and low-/high-density lipoprotein ratio (LHR) was positively correlated with β-CTX (r=0.340, P=0.010).      ③Binary logistic regression demonstrated that β-CTX was an independent risk factor for CAC (OR=3.433, 95% CI: 1.51~7.78, P=0.003).  Conclusion  Bone markers are implicated in the pathogenesis of CAC. The bone marker of β-CTX can be used as an independent factor for the prediction of CAC. Bone markers are correlated with inflammatory factors, PTH, LHR and β2-MG, and they may collectively participate in the formation of CAC through affecting bone metabolism in MHD patients.

Key words:  Bone marker, Type 1 collagen cross-linking β-C terminal peptide, Maintenance hemodialysis, Coronary artery calcification