Speech changes in neurodegenerative diseases relate to clinical outcomes

Abstract

AbstractBackgroundThe detection and characterization of speech changes may help in the identification of neurodegenerative diseases and have the potential to help with patient characterization and monitoring. Yet, there is limited research validating the presence of speech changes across different types of neurodegenerative disease. We report on the relationships between speech and other clinical assessments in the individuals with different dementia diagnoses and in comparison to healthy older adults.MethodWe analyzed speech recordings from 109 patients (52F, 57M; Age = 72.63± 8.61) who were diagnosed with various neurodegenerative diseases, including Alzheimer’s disease, Frontotemporal Dementia, and Vascular Cognitive Impairment, in a cognitive neurology memory clinic. Speech recordings of an open‐ended picture description task were processed using the Winterlight speech analysis platform which generates >500 acoustic and linguistic features. We investigated the linear relationship between the speech features and clinical assessments including the Mini Mental State Examination (MMSE), Western Aphasia Battery (WAB), and Mattis Dementia Rating Scale while controlling for age, sex and years of education. Speech features that were significantly associated with clinical measures were then included in group comparisons with healthy older adults (N = 74, ∼39F; Age = 61.31±7.29).ResultSpeech features including lexical and syntactic features were significantly correlated with clinical assessments in patients, across diagnoses. Lower MMSE scores were associated with the use of more familiar nouns (β = ‐1.60, p<.001). Similarly, increased impairment as assessed by the WAB was correlated with the use of higher frequency nouns (β = ‐0.01, p<.001). Patients used significantly more nouns (z = 6.25, p<.001) and shorter words (z = 8.33, p<.001) than the healthy older adults. Their speech duration was also significantly shorter (z = 7.98, p<.001) and they paused more (z = 5.19, p<.001).ConclusionSpeech changes representing decreased speech, with simpler vocabularies and syntax, were detectable in patients with different neurodegenerative diseases and correlated with clinical outcomes. These same speech patterns differed in patients with neurodegenerative disease compared to healthy older adults. Speech has the potential to be a sensitive measure for detecting cognitive impairments across various neurodegenerative diseases.