Salivary levels of calcium, phosphorus, potassium, albumin and correlation with serum biomarkers in hemodialysis patients.

Objectives: Evidences suggest that hemodialysis patients have reduced salivary flow and changes in the composition of salivary secretion. These changes may reflect local and systemic disorders. The objectives of this study were to compare the salivary levels of calcium (Ca), phosphorus (P), potassium (K) and albumin in hemodialysis patients and healthy subjects, and to investigate a possible correlation between their serum and salivary levels.

Design: A case-control study was conducted with 60 hemodialysis patients (HD group) and 37 systemically healthy individuals (control group). Stimulated saliva samples were collected for biochemical analysis (Ca, P, K and albumin). Serum data were collected in the HD group. Statistical analysis included t-test, Pearson correlation and simple linear regression.

Results: The HD group exhibited higher salivary levels of Ca, P, and albumin (p<0.05). There was a significant positive correlation between serum PTH and salivary phosphorus (r=0.342, p=0.009), and between serum PTH and salivary potassium (r=0.306, p=0.020). An increase of 100 pg/dL in serum PTH was associated with an elevation of salivary P levels (0.34 mg/dL, p=0.009), and salivary K levels (0.20 mmol/dL, p=0.02), in the HD group.

Conclusions: The findings suggest that HD patients present increased levels of salivary components (Ca, P, and albumin), and changes commonly observed in HD patients, such as hyperparathyroidism, appear to have an influence on salivary composition.