Correlation between Serum Bone Turnover Markers and Estimated Glomerular Filtration Rate in Chinese Patients with Diabetes

OBJECTIVE: Diabetes is a growing global public health concern with many significant disease complications. Multiple studies show that bone turnover markers (BTMs) are decreased in diabetes patients, indicating impaired bone metabolism in diabetes patients. A recent study also showed that in diabetes patients, BTMs are correlated with urine albumin to creatinine ratio, an indicator of nephropathy. However, whether BTMs are correlated with estimated glomerular filtration rate (eGFR) in diabetes remains unknown. This retrospective study accessed correlations between serum BTMs and eGFR in Chinese patients with diabetes and compare levels of BTMs and eGFR between diabetic patients and healthy individuals. METHODS: This study analyzed data from 221 diabetic patients (include type1 and type 2 diabetes) and 155 healthy individuals. Serum BTM levels and eGFR were compared between diabetic patients and healthy individuals. Pearson correlation analysis was used to assess correlations between BTMs and eGFR. Multiple logistic regression analysis adjusted for gender and age was performed to measure odd ratio (OR) and 95% confidence interval (95% CI) of BTMs on diabetes. RESULTS: Patients with diabetes had significant lower 25-hydroxyvitamin D (25(OH)D) levels (15.07 ± 6.20 ng/mL) than healthy group (17.89 ± 6.41 ng/mL) (P < 0.05). For patients with diabetes, eGFR was negatively correlated with osteocalcin (OC) (r = −0.434, P < 0.05), procollagen type 1 intact N-terminal propeptide (P1NP) (r = −0.350, P < 0.05), and β-carboxy-terminal cross-linking telopeptide of type I collagen (β-CTX) (r = −0.179, P < 0.05) levels. For healthy people, eGFR was negatively correlated with 25(OH)D (r = −0.290, P < 0.05) levels. Multiple logistic regression analysis adjusted for age and gender (mean age of diabetes was 64.9 years and the percentage of female was 66.9%, mean age of healthy people was 48.4 years and the percentage of female was 37.4%) showed that 25(OH)D (OR = 0.909, 95%CI = 0.862 − 0.959, P < 0.05) was protective factors for diabetes. CONCLUSIONS: In the stage of diabetic nephropathy, bone turnover may accelerate. It is important to detect BTMs in the stage of diabetic nephropathy.