Prevalence of swallowing disorder in different dementia subtypes among older adults: a meta-analysis

BACKGROUND

Ageing process and abnormal protein accumulation in dementia damage neural pathways affecting the swallowing process and leading to swallowing disorder.

OBJECTIVE

To estimate the prevalence of swallowing disorder among older adults with different dementia subtypes.

METHODS

We conducted a systematic search across multiple databases, including PubMed, Embase, Scopus, Web of Science and OVID Medline. The meta-analysis employed R (version 4.0.2) and utilised a generalised linear mixed model with a random-effect approach to estimate the pooled prevalence of swallowing disorder among older adults, considering various dementia subtypes. The quality of included studies was assessed using Hoy's criteria. Heterogeneity was identified through Cochrane's Q and I2 statistics. To further explore heterogeneity, moderator analysis was performed to identify the contributing variables among the included studies.

RESULTS

Eighteen studies with 12,532 older adults with different dementia subtypes were enrolled in our meta-analysis. The pooled prevalence of swallowing disorder among older adults with dementia was 58%, with 46.5% for Alzheimer's dementia, 34.9% for Parkinson's dementia, 18.8% for vascular dementia, 16.3% for mixed dementia and 12.2% for Lewy body dementia. According to assessment tools, Alzheimer's dementia had the highest prevalence, with 58% in instrumental assessments and 39% in clinical assessments. Medical history, Alzheimer's dementia, moderate-to-severe Clinical Dementia Rating, delayed oral phase, delayed pharyngeal phase and poor tongue motility contributed to the heterogeneity of the included studies.

CONCLUSIONS

More than half of older adults with dementia demonstrate to have swallowing disorder. Our findings offer valuable insights to healthcare professionals for the identification of swallowing disorder in ageing population with dementia.

The Relationship Between Dysphagia and Pneumonia in Acute Stroke Patients: A Systematic Review and Meta-Analysis

Background

Dysphagia is a common complication after stroke and is associated with the development of pneumonia. This study aimed to summarize the relationship between dysphagia and pneumonia in post-stroke patients.

Materials and Methods

Articles published up to November 2021 were searched in the PubMed, Embase, Cochrane library, and Scopus databases. Studies that investigated the development of pneumonia in acute stroke patients with and without dysphagia were included. The methodological quality of individual studies was evaluated using the Risk Of Bias In Non-randomized Studies-of Interventions tool, and publication bias was evaluated using a funnel plot and Egger's test.

Results

Of 5,314 studies, five studies were included in the meta-analysis. The results revealed that the incidence of pneumonia was significantly higher in the dysphagia group than in the non-dysphagia group (OR 9.60; 95% CI 5.75–16.04; p < 0.0001; I2 = 78%). There was no significant difference in the mortality rate between the two groups (OR 5.64; 95% CI 0.83–38.18; p = 0.08; I2 = 99%).

Conclusion

Dysphagia is a significant risk factor for pneumonia after stroke. The early diagnosis and treatment of dysphagia in stroke patients are important to prevent stroke-associated pneumonia.

Prevalence and Severity of Dysphagia Using Videofluoroscopic Swallowing Study in Patients with Aspiration Pneumonia

INTRODUCTION

The purpose of this study was to identify the prevalence and severity of dysphagia in patients diagnosed with aspiration pneumonia, with and without neurologic disorders.

METHODS

We retrospectively reviewed the medical records of inpatients with aspiration pneumonia who underwent a videofluoroscopic swallowing study (VFSS) for evaluation of dysphagia. Patients were divided into two groups based on the presence or absence of neurologic disorders. The prevalence and severity of aspiration and pharyngeal residue due to dysphagia were assessed using the penetration-aspiration scale (PAS) and pharyngeal residue grade (PRG).

RESULTS

A total of 784 patients were enrolled; of these, 58.7% were males and the mean age was 76.12 ± 6.69. Penetration-aspiration-related dysphagia (PAS scores 3-8) was seen in 56.5% of all subjects, and 32.5% showed silent aspiration (PAS 8). Pharyngeal residue-related dysphagia (PRG scores 2-3) was seen in 65.2% of all patients, and the PAS and PRG were positively correlated. On dividing the subjects into two groups based on the presence of neurologic disorders, there was no significant difference in prevalence of the dysphagia between groups (PAS: p = 0.641; PRG: p = 0.872) with the proportion of silent aspiration (p = 0.720).

CONCLUSION

In patients hospitalized for aspiration pneumonia, there was a high prevalence of dysphagia. There were no differences in the prevalence and severity of dysphagia in patients with aspiration pneumonia based on the presence or absence of a neurologic disorder. Therefore, diagnostic evaluation of dysphagia is necessary regardless of the presence of neurologic disorders.