Periodontal Inflammatory Burden and Salivary Matrix Metalloproteinase-8 Concentration Among Patients With Chronic Kidney Disease at the Predialysis Stage.

BACKGROUND: The aim of the present study is to compare periodontal inflammatory burden related to the salivary matrix metalloproteinase (MMP)-8 concentration among patients with chronic kidney disease (CKD) at the predialysis stage. METHODS: Salivary samples from 118 predialysis patients were assayed for MMP-8 by immunofluorometric assay. Of the patients, 43 (36%) had diabetic nephropathy, whereas 75 (64%) had other kidney disease. Clinical and radiographic oral health examination was made at Helsinki University Hospital. Oral and general health data including laboratory findings were recorded from hospital records, and the periodontal inflammatory burden index (PIBI) and the total dental index (TDI) were calculated. Results were analyzed with cross tabulation, Pearson χ(2) test, and Mann-Whitney U test. RESULTS: Results included elevated PIBI, increased TDI, and two or more sites with ≥ 6 mm or deeper periodontal pocket, associated with elevated salivary MMP-8 concentrations (P < 0.05 in all associations). The diabetic nephropathy group and patients with high hemoglobin A1c (HbA1c) values (≥ 6.5%, ≥ 48 mmol/mol) exerted slightly elevated median salivary MMP-8 values compared with the other CKD group or regarding patients with HbA1c values < 6.5%, but these differences were not statistically significant. CONCLUSIONS: Elevated salivary MMP-8 associated significantly with more severe oral/periodontal inflammatory burden among patients with CKD at the predialysis stage. Thus, salivary MMP-8 analysis could give adjunctive information regarding oral health.