Sensitivity and specificity of the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised to detect dysarthria in individuals with amyotrophic lateral sclerosis.

INTRODUCTION/AIMS: Given the widespread use of the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) to measure disease progression in ALS and recent reports demonstrating its poor sensitivity, we aimed to determine the sensitivity and specificity of the ALSFRS-R bulbar subscale and speech item to detect validated clinical ratings of dysarthria in individuals with ALS. METHODS: Paired ALSFRS-R and validated Speech Intelligibility Test (SIT) data from individuals with ALS were analyzed. Trained raters completed duplicate, independent, and blinded ratings of audio recordings to obtain speech intelligibility (%) and speaking rate (words per minute, WPM). Binary dysarthria profiles were derived (dysarthria ≤96% intelligible and/or <150 WPM). Data were obtained using the Kruskal-Wallis test, receiver-operating characteristic (ROC) curve, area under the curve (AUC), sensitivity and specificity percentages, and positive/negative predictive values (PPV/NPV). RESULTS: A total of 250 paired SIT and ALSFRS-R data points were analyzed. Dysarthria was confirmed in 72.4% (n = 181). Dysarthric speakers demonstrated lower ALSFRS-R bulbar subscale (8.9 vs. 11.2) and speech item (2.7 vs. 3.7) scores (P < .0001). The ALSFRS-R bulbar subscale score had an AUC of 0.81 (95% confidence interval [CI] 0.75 to 0.86). A subscale score of ≤11 yielded a sensitivity of 86%, specificity of 57%, PPV of 84%, and NPV of 60% to correctly identify dysarthria status. The ALSFRS-R speech item score demonstrated an AUC of 0.81 to detect dysarthria (95% CI 0.76 to 0.85), with sensitivity of 79%, specificity of 75%, PPV of 89%, and NPV of 58% for a speech item cutpoint of ≤3. DISCUSSION: The ALSFRS-R bulbar and speech item subscale scores may be useful, inexpensive, and quick tools for monitoring dysarthria status in ALS.

Profiles of Dysarthria and Dysphagia in Individuals With Amyotrophic Lateral Sclerosis.

PURPOSE: While dysarthria and dysphagia are known bulbar manifestations of amyotrophic lateral sclerosis (ALS), the relative prevalence of speech and swallowing impairments and whether these bulbar symptoms emerge at the same time point or progress at similar rates is not yet clear. We, therefore, sought to determine the relative prevalence of speech and swallowing impairments in a cohort of individuals with ALS and to determine the impact of disease duration, severity, and onset type on bulbar impairments. METHOD: Eighty-eight individuals with a confirmed diagnosis of ALS completed the ALS Functional Rating Scale-Revised (ALSFRS-R), underwent videofluoroscopy (VF), and completed the Sentence Intelligibility Test (SIT) during a single visit. Demographic variables including disease duration and onset type were also obtained from participants. Duplicate, independent, and blinded ratings were completed using the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale and SIT to index dysphagia (DIGEST ≥ 1) and dysarthria (< 96% intelligible and/or < 150 words per minute) status. Descriptive statistics, Pearson chi-squared tests, independent-samples t tests, and odds ratios were performed. RESULTS: Dysphagia and dysarthria were instrumentally confirmed in 68% and 78% of individuals with ALS, respectively. Dysarthria and dysphagia were associated (p = .01), and bulbar impairment profile distributions in rank order included (a) dysphagia - dysarthria (59%, n = 52), (b) no dysphagia - dysarthria (19%, n = 17), (c) no dysphagia - no dysarthria (13%, n = 11), and (d) dysphagia - no dysarthria (9%, n = 8). Participants with dysphagia or dysarthria demonstrated 4.2 higher odds of exhibiting a bulbar impairment in the other domain than participants with normal speech and swallowing (95% CI [1.5, 12.2]). There were no differences in ALSFRS-R total scores or disease duration across bulbar impairment profiles (p > .05). ALSFRS-R bulbar subscale scores were significantly lower in individuals with dysphagia versus no dysphagia (8.4 vs. 10.4, p < .0001) and dysarthria versus no dysarthria (8.5 vs. 10.9, p < .0001). Dysphagia and onset type (p = .003) and dysarthria and onset type were associated (p < .0001). CONCLUSIONS: Over half of the individuals with ALS in this study demonstrated both dysphagia and dysarthria. Of those with only one bulbar impairment, speech was twice as likely to be the first bulbar symptom to degrade. Future studies are needed to confirm these findings and determine the longitudinal progression of bulbar impairments in this patient population.

Diagnostic utility of the amyotrophic lateral sclerosis Functional Rating Scale-Revised to detect pharyngeal dysphagia in individuals with amyotrophic lateral sclerosis.

OBJECTIVE: The ALS Functional Rating Scale-Revised (ALSFRS-R) is the most commonly utilized instrument to index bulbar function in both clinical and research settings. We therefore aimed to evaluate the diagnostic utility of the ALSFRS-R bulbar subscale and swallowing item to detect radiographically confirmed impairments in swallowing safety (penetration or aspiration) and global pharyngeal swallowing function in individuals with ALS. METHODS: Two-hundred and one individuals with ALS completed the ALSFRS-R and the gold standard videofluoroscopic swallowing exam (VFSE). Validated outcomes including the Penetration-Aspiration Scale (PAS) and Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) were assessed in duplicate by independent and blinded raters. Receiver operator characteristic curve analyses were performed to assess accuracy of the ALSFRS-R bulbar subscale and swallowing item to detect radiographically confirmed unsafe swallowing (PAS > 3) and global pharyngeal dysphagia (DIGEST >1). RESULTS: Although below acceptable screening tool criterion, a score of ≤ 3 on the ALSFRS-R swallowing item optimized classification accuracy to detect global pharyngeal dysphagia (sensitivity: 68%, specificity: 64%, AUC: 0.68) and penetration/aspiration (sensitivity: 79%, specificity: 60%, AUC: 0.72). Depending on score selection, sensitivity and specificity of the ALSFRS-R bulbar subscale ranged between 34-94%. A score of < 9 optimized classification accuracy to detect global pharyngeal dysphagia (sensitivity: 68%, specificity: 68%, AUC: 0.76) and unsafe swallowing (sensitivity:78%, specificity:62%, AUC: 0.73). CONCLUSIONS: The ALSFRS-R bulbar subscale or swallowing item did not demonstrate adequate diagnostic accuracy to detect radiographically confirmed swallowing impairment. These results suggest the need for alternate screens for dysphagia in ALS.