Salivary alterations in type 2 (non-insulin-dependent) diabetes mellitus and hypertension.

OBJECTIVES: The aim of this study was to determine whether saliva output and composition are altered in type 2 diabetes mellitus by comparison with a healthy, non-medicated control group, and also a group of hypertensives.
METHODS: From a community-dwelling cohort of Mexican American and European American subjects enrolled in the OH:SALSA oral aging study, we identified 233 subjects with type 2 diabetes mellitus, 227 with hypertension, and 240 healthy control subjects. We collected unstimulated whole (UW) and submandibular/ sublingual (US) saliva, as well as stimulated parotid (SP) and submandibular/ sublingual (SS) saliva. Flow rates were determined, yeast carriage was assayed in UW saliva, and SP and SS saliva samples were analyzed for protein composition. ELISA was used to determine concentrations of an array of specific protein components, with both antimicrobial and other activities.
RESULTS: Both diabetic and hypertensive subjects had reduced output of both stimulated and unstimulated submandibular/sublingual saliva. 30% of the diabetic subjects had high oral yeast counts (> or =1000 cfu/mL) compared with 17% of the healthy subjects and 20% of the hypertensives. Significant increases in the concentrations of a number of the protein components were found in the diabetic subjects, specifically, SP lactoferrin, myeloperoxidase (MPO), and salivary peroxidase (SPO), as well as SS total protein, albumin, lactoferrin and secretory IgA.
CONCLUSIONS: The pattern of decreased flow rates and increased protein concentrations were similar, but consistently greater in diabetics than hypertensives, suggesting that disease-specific mechanisms may be responsible. Diabetics may be more prone to oral dryness and infections than non-diabetics.