Evaluation of salivary biomarkers in chronic kidney disease: A systematic review and meta-analysis.
Source: PubMed, NCBI / U.S. National Library of Medicine
Chronic Kidney Disease (CKD) is a growing global health concern, affecting more than 800 million people worldwide. CKD leads to progressive and irreversible loss of renal function, and its early diagnosis is essential to prevent complications and improve patient outcomes. Saliva has gained attention as a potential alternative to blood-based diagnostics. This systematic review and meta-analysis aimed to evaluate the salivary levels of key biomarkers (urea, creatinine, calcium, phosphorus, and pH) in patients with CKD compared to healthy individuals. A systematic search was conducted in PubMed, Scopus, and Web of Science databases for articles published from January 2000 to January 2025. A total of 340 articles were initially retrieved, and after screening, 35 eligible studies were included: 12 case-controls and 20 cross-sectional. Data were extracted and analyzed using STATA version 17 software. Meta-analysis revealed that salivary levels of urea, creatinine, calcium, and pH were significantly higher in CKD patients (p < 0.05), while phosphorus showed no significant difference (p = 0.196). High heterogeneity was observed in the case-control studies included in the meta-analysis (I > 75%). Salivary biomarkers, especially urea and creatinine, show potential as non-invasive indicators for CKD detection and monitoring. These findings support the use of saliva as a diagnostic fluid, particularly in patients with blood sampling limitations.