The Importance of Bone Biomarkers in the Diagnosis of Renal Osteodystrophy

Objective: To evaluate the association of serum biochemical markers in patients with chronic kidney disease (CKD) in Jamaica for early detection of renal osteodystrophy (ROD). Methods: The study contained two groups: CKD group (221) which consisted of adult patients, from dialysis units and renal clinics, with stage III to V CKD. The control group (237) had adult individuals, from the medical outpatient clinics, with mild and controlled chronic diseases and absence of renal failure. The patients in the study were between 18-80 years of age and gave informed consent to participate in the study The differences in distribution of demographic, clinical and pathologic variables between the two groups were evaluated. Pearson's chi-squared test and Spearman' rho correlation coefficient test was used, with p < 0.01 considered statistically significant. Data analysis was conducted using the statistical package for the social sciences (SPSS) version 17.0. Results: Among the 221 CKD patients in the study, 174 (78.7%) had ROD based on serum intact parathyroid hormone (iPTH) levels. The majority of patients in the control group did not have bone disease ie 95-96%. The majority of CKD patients (70.0%) had high-turnover (HTO) bone disease compared to 29.3% of patients with low-turnover (LTO) bone disease. Dialysis patients who had HTO bone disease compared with those with LTO had significantly higher levels of iPTH and total serum alkaline phosphatase (ALP). A similar relationship was observed among CKD patients not on dialysis. There was a significant individual variation in bone turnover biochemical markers. A total of 237 patients were recruited in the control group. Based on the levels of iPTH and tALP, six of them were found to have bone disease. The majority of these patients with bone disease were diabetic (83.3%) while the other patient had cancer (16.7%). The six patients in the control group with bone disease were within the age cohort of 64-80 years, most of whom were 78 years old. Conclusion: A combination of serum biochemical markers might predict underlying renal osteodystrophy better that would individual biochemical markers. A predictive model using bone histology and biochemical markers can be developed in the future.