Prevalence of and risk factors for dysphagia in the community dwelling elderly: A systematic review

This review clarifies current information regarding the prevalence of and risk factors associated with dysphagia (swallowing disorders) in the community dwelling elderly (CDE). A better understanding of prevalence and characteristics of dysphagia in the CDE will help to determine the scope of this problem. Understanding the scope of dysphagia is a critical first step towards early identification, management, and prevention of dysphagia related morbidities in the CDE. Studies identified from multiple electronic databases (MEDLINE (Pubmed), PsychInfo, Google Scholar, EBSCO, PROQUEST, Web of Science and WorldCat dissertations and theses) evaluating prevalence and risk factors for dysphagia in the CDE were reviewed. Data from all eligible studies were abstracted by the first author and independently reviewed by two raters, using the Newcastle-Ottawa scale (NOS). 15 studies (n = 9947 participants) were eligible for inclusion. Studies included were all observational: 14 cross-sectional and 1 prospective cohort. Significant heterogeneity was observed in methodology among studies of dysphagia in the CDE. The average NOS study quality rating was 4.54 points (SD: 0.9), with a mode of 4 points (range 3-6). Only 6 of the 15 studies were identified as high quality research studies, with a mean of 5.33 points (SD: 0.47). Among reviewed studies, the prevalence of swallowing difficulty in the CDE ranged from 5% to 72%. However, the average prevalence of dysphagia estimated from the 6 high quality studies was 15%. Reported risk factors associated with dysphagia include advancing age; history of clinical disease; and physical frailty, including reduced ability to carry out activities of daily living. Research on dysphagia in CDE is modest and consists mostly of observational studies with diverse methodology. However, prevalence rate of 15% from the high quality research suggests a significant public health impact of this impairment. Identification of specific risk factors that cause dysphagia in the CDE is premature, given the rigor of published studies. Future research efforts should focus on developing a valid definition and assessment of dysphagia in this population before clarifying causative risk factors.