Can the Repetitive Saliva Swallowing Test Be Used as a Screening Method for the Elderly Patients with Dysphagia Treated in Nursing Homes？

Abstract

The repetitive saliva swallowing test (RSST) was developed by Saito in 1996 to detect the difficulty in food ingestion and swallowing．ln this screening test those who swallow their saliva more than three times within 30 seconds are regarded as those with normal food ingestion and swallowing functions． ln order to evaluate the usefulness of RSST as a screening test for the detection of difficulty in food ingestion and swallowing， we studied the relationship between dysphagia and the frequency of saliva swallowing． The subjects were 1098 elderly patients who were under care in 17 nursing homes in Sapporo and the surrounding area． The nursing staff carefully observed their eating and swallowing behavior and judged the presence of dysphagia during or after meals． The ratio of men to women was 1 to 2.5 and their average age was 82.2 years． Of 1098 patients， 1048 were available for RSST．The incidence of dysphagia was 13.1％ (137/1048). According to the results of RSST， 392 patients could swallow their saliva more than three times within 30 seconds． Those who swallowed their saliva more frequently within the specified period showed a lower incidence of dysphagia． We divided the subjects into two groups：a group of elderly patients who swallowed their saliva less than twice （n＝656） and a group of elderly patients who swallowed their saliva more than three times (n＝392). The number of those with dysphagia was 110 patients in the former group and 27 in the latter group． There was a statistically significant difference between these two groups (p＜0.001). The sensitivity and specificity of RSST were 80.3％ and 40.1％ respectively． On the basis of these test results， we concluded that RSST was a useful screening method to detect the difficulty of food ingestion and swallowing in the elderly patients treated in nursing homes．