Abstract DP125: Silent Dysphagia After Stroke: Prevalence, Risk Factors, and Clinical Implications from a Pilot Cohort Study

Introduction: Persistent swallowing impairment (dysphagia) after stroke contributes significantly to morbidity, mortality, and reduced quality of life. A subset of patients exhibit “silent dysphagia,” in which clinically significant swallowing impairments occur without reported symptoms, often due to sensory or cognitive deficits. These individuals are rarely referred for instrumental swallow assessment, creating a critical evidence gap in post-discharge stroke care. Methods: Data were collected from a cross-sectional, convenience sample of individuals ≥3 months post-ischemic stroke. All participants completed the Eating Assessment Tool-10 (EAT-10) and underwent videofluoroscopic swallow studies analyzed by two blinded raters using the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST). Participants (N=45) were classified into three groups: no dysphagia (DIGEST=0), overt dysphagia (DIGEST≥1 and EAT-10>3), and silent dysphagia (DIGEST≥1 and EAT-10≤3). Descriptive statistics, Fisher’s exact tests, and Spearman correlations were used to evaluate differences across groups by age, sex, lesion location, and NIH Stroke Scale (NIHSS) scores. Results: Forty-five participants were included: no dysphagia (n=25), overt dysphagia (n=13), and silent dysphagia (n=7). Mean age was lowest in the silent dysphagia group (58.0 ± 5.9 years), compared to overt (69.2 ± 11.7) and no dysphagia (64.8 ± 13.0), though not statistically significant (p=0.12). All participants with silent dysphagia were male, compared to 56% of overt and 77% of no dysphagia groups (p=0.074). Lesion location did not differ significantly between groups ( p = 0.818). EAT-10 and DIGEST scores were weakly correlated (r=0.211, p=0.163), as were NIHSS scores with EAT-10 and DIGEST (r=0.243 and r=0.090, respectively). Conclusions: Silent dysphagia was identified in 16% of this ambulatory post-stroke cohort. These preliminary findings underscore the need for larger studies to better characterize clinical features of silent dysphagia. As this sample was mildly impaired, we hypothesize the true prevalence may be higher. Improved identification of patients at risk may optimize referrals for follow-up imaging during stroke recovery to detect silent physiologic deficits that may otherwise go untreated and lead to complications such as aspiration pneumonia or readmission.