Reference intervals for saliva analytes collected by a standardized method in a physically active population

ObjectivesOur aims were to test a liquid-based saliva collection system for total antioxidant status (TAS), uric acid (UA), total protein concentration (TP) and salivary alpha-amylase (SAA) activity; to determine if these analytes in serum and saliva are correlated in a physically active population and to establish reference intervals for these parameters.Design and methodsParticipants in this study were 115 physically active males (18–20 years old). Saliva samples were collected using the Saliva Collection System (Greiner Bio-One®) immediately before obtaining blood. Biochemical analyses were conducted using an Autolab Boehringer analyzer.ResultsWe found a correlation between UA and TP concentrations in serum and saliva samples. The reference intervals for TP and SAA activity in the morning were lower than in the afternoon (p < 0.0001). The reference intervals for UA and TAS did not vary with the time of collection.ConclusionThe establishment of reference intervals for these saliva constituents increases their diagnostic utility and allows for detection of physiological or pathological states.

► Saliva may be an alternative to blood for determining various analytes.
► Our results showed specific reference intervals for salivary analyses.
► Some salivary analytes could be influenced by circadian rhythms and physical training.