Detection of Mild Hyposalivation in Elderly People Based on the Chewing Time of Specifically Designed Disc Tests: Diagnostic Accuracy

Abstract

To compare sialometry with chewing time (including swallowing) of specifically designed disc tests. Index test versus reference standard (sialometry; 60 patients); reliability study (10 patients). Outpatient dental clinic and geriatric ward, Nice University Hospital, France. Thirty adults and 30 older patients (mean ages 47 and 84). Index test assessment in patients with and without hyposalivation. Data from medical files, interviews and oral examination were collected. Sialometry (stimulated salivary flow rate (SSFR) mL/min) and disc chewing times (seconds) were measured. Sialometry was too long and was inappropriate for five of the 30 older persons. Chewing times were negatively correlated to sialometry results (Spearman correlation coefficient (R)=0.77, P<.001). The threshold to diagnose hyposalivation (SSFR <1 mL/min) was 40 seconds (area under the receiver operating characteristic curve (AUC)=0.921, 100% sensitivity, 72% specificity). Twenty-seven subjects with a SSFR less than 1.5 mL/min had a chewing time longer than 40 seconds, suggesting that mild hyposalivation and eating difficulties were related (AUC=0.941, 93% sensitivity, 88% specificity). Mean chewing time was greater with xerostomia (51.9 vs 30.7 seconds, P<.001) but not with dental pain (39.5 vs 39.9, P=.96). Masticatory percentage (e.g., pairs of antagonistic teeth) had no effect on chewing time (SSFR <1 mL/min, AUC=0.921; SSFR <1.5 mL/min, AUC=0.950). Reliability was better for the disc test than for sialometry (intraclass correlation 0.85 vs 0.70). This disc test was conceived to detect mild hyposalivation in geriatric patients with impaired dental health. Early detection of hyposalivation could help to suppress or avoid xerostomia-inducing drugs and to prevent oral infections and dental caries.