Diagnostic accuracy of lip force and tongue strength for sarcopenic dysphagia in older inpatients: A cross-sectional observational study.

BACKGROUND & AIMS: Dysphagia can be caused by sarcopenia in older adults. Although sarcopenic dysphagia has been reported to be associated with low tongue strength, whether tongue strength can be useful as a diagnostic index for sarcopenic dysphagia remains unclear. In addition, the association between sarcopenic dysphagia and lip force is unknown. The aim of the present study was to clarify the association of lip force and tongue strength with sarcopenic dysphagia, and their diagnostic accuracy for sarcopenic dysphagia.

METHODS: A cross-sectional study was conducted in consecutive 245 (166 women) inpatients aged ≥65 years in the post-acute phase of illness. The presence of sarcopenic dysphagia, lip force, and tongue strength were assessed. Additional factors were also assessed: cognitive function, nutritional status, comorbidity, oral intake level, occlusion status, physical function, and inflammatory status. Multivariable logistic regression analysis was conducted with the presence of sarcopenic dysphagia as a dependent variable. Lip force and tongue strength were assessed with the area under the receiver operating characteristic curve (AUC) to clarify diagnostic accuracy for sarcopenic dysphagia. In addition, the cut-off values of lip force and tongue strength for identifying sarcopenic dysphagia were determined according to sex.

RESULTS: In total, 86 patients (35.1%) had sarcopenic dysphagia. Both men and women with sarcopenic dysphagia had lower lip force and tongue strength than men and women without dysphagia or sarcopenic dysphagia (p < 0.001 for all). In multivariable logistic regression analysis, sarcopenic dysphagia was significantly associated with lip force (OR = 0.63, 95% CI 0.53-0.74, p < 0.001) and tongue strength (OR = 0.92, 95% CI 0.87-0.98, p = 0.011). The AUCs for lip force in patients with sarcopenic dysphagia were 0.88 (CI 0.81-0.95, p < 0.001) for men and 0.84 (CI 0.77-0.90, p < 0.001) for women. The AUCs for tongue strength were 0.79 (CI 0.69-0.89, p < 0.001) for men and 0.74 (CI 0.65-0.82, p < 0.001) for women. The cut-off values for sarcopenic dysphagia in men were 10.4 N for lip force and 24.3 kPa for tongue strength; the cut-off values in women were 8.5 N for lip force and 23.9 kPa for tongue strength.

CONCLUSION: In older inpatients who are suspected as having dysfunction due to sarcopenia, lip force and tongue strength can be independently useful indices for diagnosing sarcopenic dysphagia, and may be factors that prevent and improve sarcopenic dysphagia.