Reduced Maximum Pitch Elevation Predicts Silent Aspiration of Small Liquid Volumes in Stroke Patients

Abstract

Background and purposePreliminary evidence has shown that reduced ability to maximally raise vocal pitch correlates with the occurrence of aspiration (i.e., airway invasion by food or liquid). However, it is unclear if this simple task can be used as a reliable predictor of aspiration in stroke patients. Our aim was to examine whether maximum vocal pitch elevation predicted airway invasion and dysphagia in stroke.MethodsForty-five consecutive stroke patients (<1 month poststroke) at a rehabilitation setting participated in a videofluoroscopic swallow study and two maximum vocal pitch elevation tasks. Maximum pitch was evaluated acoustically [maximum fundamental frequency (max F0)] and perceptually. Swallowing safety was rated using the Penetration/Aspiration Scale and swallowing performance was assessed using components of the Modified Barium Swallow Impairment Profile (MBSImPTM©). Data were analyzed using simple regression and receiver operating characteristics curves to test the sensitivity and specificity of max F0 in predicting aspiration. Correlations between max F0 and MBSImP variables were also examined.ResultsMax F0 predicted silent aspiration of small liquid volumes with 80% sensitivity and 65% specificity (p = 0.023; area under the curve: 0.815; cutoff value of 359.03 Hz). Max F0 did not predict non-silent aspiration or penetration in this sample and did not significantly correlate with MBSImP variables. Furthermore, all participants who aspirated silently on small liquid volumes (11% of sample) had suffered cortical or subcortical lesions.ConclusionIn stroke patients (<1 month poststroke), reduced maximum pitch elevation predicts silent aspiration of small liquid volumes with high sensitivity and moderate specificity. Future large-scale studies focusing on further validating this finding and exploring the value of this simple and non-invasive tool as part of a dysphagia screening are warranted.

The Diagnostic Accuracy of the Pitch Glide to Identify Aspiration in Patients with Respiratory Diseases: A Pilot Study

“…Additionally, it was discovered that lower maximum F 0 was associated with higher penetration-aspiration scores. These results support the findings of the two previous studies which reported that reduced pitch glide can accurately predict aspiration on small liquid boluses [37, 38]. However, the sample size of our study was small, and results should be validated in a future study including a bigger sample size.…”

“…Although previous evidence suggests that auditory-perceptual results of the pitch glide were accurate in predicting aspiration and there were adequate correlations between auditory-perceptual ratings and aspiration, in our study it was revealed that auditory-perceptual analysis of the pitch glide had inadequate sensitivity and specificity [37, 38]. Correlations between auditory-perceptual results of the pitch glide and aspiration status were also weak in the current study.…”

“…Preliminary studies have been conducted to explore the link between pitch glide and aspiration in people with dysphagia [37, 38]. Malandraki et al [37] examined the correlations between the pitch glide and aspiration in a videofluoroscopic swallowing study (VFSS) in 40 adults with different aetiologies of dysphagia.…”

“…Additionally, pitch glide was found to have adequate correlations with residue scores. More recently, Rajappa et al [38] examined the diagnostic accuracy of the pitch glides /a/ and /i/ in identifying people who aspirated after stroke. The results of this study suggested that pitch glide can predict silent aspiration in small liquid boluses with high sensitivity and moderate specificity.…”

“…The results of this study suggested that pitch glide can predict silent aspiration in small liquid boluses with high sensitivity and moderate specificity. However, there were no correlations observed between pitch glide and residue and ­hyolaryngeal excursion [38].…”