The Association Between Dysphagia Symptoms, DIGEST Scores, and Severity Ratings in Individuals with Parkinson's Disease

The Swallow Disturbance Questionnaire (SDQ) is a screening tool developed to identify patients with Parkinson's Disease (PD) in need of objective swallowing evaluation. In a previous investigation, the SDQ did not predict abnormal airway protection on a videofluoroscopic swallowing study (VFSS). This investigation was undertaken to determine whether SDQ scores were more accurate when a global measure was used. The Dynamic Imaging Grade for Swallowing Toxicity (DIGEST) is a validated measure that provides a safety, efficiency, and total severity grade based on VFSS. A secondary analysis was performed using data from 20 patients with PD who had participated in a standardized VFSS protocol. The study sample was predominantly male (80%) with an average age of 71 years, and an average PD duration of 9 years. Using an established cut-off score, participants were subdivided into those with "normal" (n = 10) and "abnormal" SDQ scores (n = 10). Recordings were scored using the DIGEST protocol by two blinded raters who also rated overall dysphagia severity from the VFSS. There was good agreement between the two raters on the DIGEST and strong correlations between DIGEST scores and clinician perceptions of dysphagia severity. Higher SDQ scores were associated with poorer Efficiency on the DIGEST but not Safety or Total scores. Consistent with other PD studies, subjective perceptions of dysphagia were poorly predictive of objective findings on VFSS. There is little information about the validity of the DIGEST for rating neurogenic dysphagia. Our study provides preliminary support for the use of the DIGEST in the PD population.