Inverse relationship of bone mineral density and serum level of N-terminal pro-B-type natriuretic peptide in peritoneal dialysis patients

Objective: Chronic kidney disease is associated with decreased bone mineral density (BMD). In this study, the relationship between BMD and the fasting serum concentration of N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) was evaluated in peritoneal dialysis (PD) patients. Material and Methods: Fasting blood samples were obtained from 52 PD patients. BMD was measured by dual energy X-ray absorptiometry of the lumbar vertebrae (L2-L4). The serum NT-pro-BNP level was measured by an electrochemiluminescence immunoassay. Results: Ten patients (19.2%) had osteoporosis, 23 patients (44.2%) had osteopenia, and 19 patients had normal BMD. Increased serum NT-pro-BNP (p < 0.001), advanced age (p = 0.012), decreased body mass index (p = 0.006), body height (p = 0.018), and body weight (p = 0.004) were associated with lower lumbar T-scores, but sex, menopausal status, PD modality, diabetes mellitus, and hypertension were not. Multivariate forward stepwise linear regression analysis with adjustment for age, body height, body weight, body mass index, and log-NT-pro-BNP indicated that a high serum level of log-NT-pro-BNP (R² change = 0.346; p < 0.001) and low body weight (R² change = 0.208; p < 0.001) were significantly and independently associated with poor lumbar BMD. Conclusion: A high serum level of NT-pro-BNP and low body weight were associated with poor BMD in PD patients.