This study aimed to longitudinally investigate the temporal relationship between tongue pressure and malnutrition in older adults with dysphagia and to determine the antecedent factors.

This is a retrospective cohort study.

In total, 177 participants aged ≥65 years with dysphagia who visited a specialized dysphagia rehabilitation clinic between 2014 and 2018 were enrolled.

Malnutrition was assessed based on the phenotypic criteria (unintentional weight loss, low body mass index, and reduced skeletal muscle mass) from the Global Leadership Initiative on Malnutrition framework. Tongue pressure was measured using a tongue pressure measuring device. The bidirectional association between tongue pressure and malnutrition was examined, adjusting for age, sex, cognitive function, occlusal support status, and comorbidities.

In the Cross-Lagged Panel Model, a significant cross-lagged effect was observed from tongue pressure to malnutrition at 6 months (β = −0.135, p < 0.001) and 12 months (β = −0.112, p = 0.028). However, the pathway from malnutrition to tongue pressure was not significant. Logistic regression analysis also revealed that baseline tongue pressure was significantly associated with malnutrition at 6 months (odds ratio [OR] = 0.91, 95% confidence interval [CI]: 0.86–0.95) and 12 months (OR = 0.89, 95% CI: 0.84–0.94). During the follow-up period, tongue pressure improved; however, the prevalence of malnutrition increased.

Decreased tongue pressure may precede malnutrition in older adults with dysphagia; however, a reverse relationship was not observed. The findings suggest the importance of incorporating oral function assessment as part of the risk assessment for malnutrition.