Meta-analysis and moderator analysis of the prevalence of malnutrition and malnutrition risk among older adults with dementia

Background: Aging and dementia are common and closely related health problems in older adults, affecting their ability to maintain a healthy diet and ultimately resulting in malnutrition. Objective: In this study, we estimated the global prevalence of malnutrition and malnutrition risk in older adults with dementia. Design: Meta-analysis. Data sources: Embase, Ovid MEDLINE, PubMed, CINAHL, Scopus, and Web of Science were comprehensively searched for articles published from database inception to October 2022. Methods: Pooled prevalence analysis was conducted using a generalized linear mixed model and a random-effects model. I² and Cochran's Q statistics were used for identifying heterogeneity. Publication bias was evaluated using Peters' regression test and a funnel plot. Moderator analyses were conducted to investigate variations in the prevalence estimates of the included studies. All statistical analyses were conducted using R software. Results: A total of 16 studies involving a total of 6513 older adults with dementia were included in the analysis. The results indicated that 32.52 % (95 % confidence interval: 19.55–45.49) of all included older adults with dementia had malnutrition, whereas 46.80 % (95 % confidence interval: 38.90–54.70) had a risk of malnutrition. The prevalence of malnutrition was found to be high among older patients living in institutionalized settings (46.59 %) and those with Alzheimer's disease (12.26 %). The factors moderating the prevalence of malnutrition included adequate vitamin B₁₂ consumption, risk behaviors, medical comorbidities, and certain neuropsychiatric symptoms. The prevalence of malnutrition risk was high among women (29.84 %) and patients with Alzheimer's disease (26.29 %). The factors moderating the prevalence of malnutrition risk included total cholesterol level, vitamin B₁₂ consumption, risk behaviors, medical comorbidities, and certain neuropsychiatric symptoms. Conclusions: Approximately one-third of older adults with dementia are malnourished and nearly half of older adults are at a risk of malnutrition. Encouraging collaboration among health-care professionals and ensuring early assessment and effective management of malnutrition are crucial for maintaining a favorable nutritional status in older adults with dementia. Registration: This study was registered with the International Prospective Register of Systematic Reviews (PROSPERO: CRD42022369329). Tweetable abstract: Globally, approximately 32.52 % of older adults with dementia are malnourished and approximately 46.80 % are at a risk of malnutrition.