Can Unstimulated Whole Salivary Flow Objectively Classify Salivary Gland Secretory Function in Sjögren’s Syndrome?

The aim of this study is to investigate whether the testing time for unstimulated whole salivary flow (UWSF) can be shortened to 5 min in patients with suspected Sjögren’s syndrome (SjS); and which SjS patients can use UWSF to evaluate salivary gland (SG) secretory function. A diagnostic cohort comprising suspected SjS patients was conducted to investigate the correlation between UWSF measurements taken at 10 min (UWSF_10 min) and those taken at 5 min (UWSF_5 min). A group of SjS patients was enrolled for a comparison between UWSF and stimulated whole salivary flow (SWSF). In 734 suspected SjS patients, there was a remarkably high concordance between UWSF_10 min and UWSF_5 min (ICC 0.970, P < 0.001; r 0.973, P < 0.001). Reducing the testing time for UWSF to 5 min resulted in a high PPV of 83.8