Objective  To investigate the status of osteoporosis and cardiovascular calcification in patients with chronic kidney disease (CKD) with different stages, and analyze the correlation between the stages and markers of bone metabolism To correlation.

  Methods  A total of 368 CKD patients at stage 3-5 who were treated in First Affiliated Hospital Affiliate to Chongqing Medical University and Chongqing Fuling Central Hospital from July 2017 to January 2018 were enrolled. A total of 60 healthy people who underwent physical examination in the hospital during the same period were enrolled as control group. Age, gender and body mass index (BMI) of all study objects at enrollment time were collected. The levels of estimate glomerular filtration rate (eGFR), serum calcium (Ca), phosphorus (P), albumin (ALB), intact parathyroid hormone (iPTH), bone alkaline phosphatase (BALP), procollagen Ⅰ N-terminal peptide (PINP) and β-crosslaps (β-CTX) were detected. The occurrence of osteoporosis, vascular calcification and heart valve calcification was detected. Pearson correlation analysis was applied to analyze correlation between eGFR, serum bone metabolism markers and osteoporosis, cardiovascular calcification.

  Results  Compared with control group, levels of serum P, iPTH, BALP, PINP and β-CTX were significantly increased in CKD stage 3-5 group (P<0.05), while levels of eGFR and serum Ca were decreased (P<0.05). With the increase of CKD staging, changes of their levels were more significant (P<0.05). The incidence of vascular calcification and heart valve calcification in CKD stage 5 hemodialysis group was higher than that in CKD stage 3-4 group and CKD stage 5 without dialysis group (P<0.05). eGFR was positively correlated with serum Ca in CKD patients at stage 3-5 (P<0.05), while negatively correlated with serum P, iPTH, BALP, PINP and β-CTX (P<0.05). The occurrence of osteoporosis, vascular calcification and heart valve calcification was negatively correlated with increase of eGFR and serum Ca levels in CKD patients at stage 3-5 (P<0.05), while positively correlated with increase of levels of serum P, iPTH, BALP, PINP and β-CTX (P<0.05).

  Conclusion  The levels of serum bone metabolism markers and eGFR are closely related to occurrence of osteoporosis and cardiovascular calcification in CKD patients at stage 3-5.