Oral frailty indicators to target major adverse health-related outcomes in older age: a systematic review

Abstract

A well-preserved oral function is key to accomplishing essential daily tasks. However, in geriatric medicine and gerodontology, as age-related physiological decline disrupts several biological systems pathways, achieving this objective may pose a challenge. We aimed to make a systematic review of the existing literature on the relationships between poor oral health indicators contributing to the oral frailty phenotype, defined as an age-related gradual loss of oral function together with a decline in cognitive and physical functions, and a cluster of major adverse health-related outcomes in older age, including mortality, physical frailty, functional disability, quality of life, hospitalization, and falls. Six different electronic databases were consulted by two independent researchers, who found 68 eligible studies published from database inception to September 10, 2022. The risk of bias was evaluated using the National Institutes of Health Quality Assessment Toolkits for Observational Cohort and Cross-Sectional Studies. The study is registered on PROSPERO (CRD42021241075). Eleven different indicators of oral health were found to be related to adverse outcomes, which we grouped into four different categories: oral health status deterioration; decline in oral motor skills; chewing, swallowing, and saliva disorders; and oral pain. Oral health status deterioration, mostly number of teeth, was most frequently associated with all six adverse health-related outcomes, followed by chewing, swallowing, and saliva disorders associated with mortality, physical frailty, functional disability, hospitalization, and falls, then decline in oral motor skills associated with mortality, physical frailty, functional disability, hospitalization, and quality of life, and finally oral pain was associated only with physical frailty. The present findings could help to assess the contribution of each oral health indicator to the development of major adverse health-related outcomes in older age. These have important implications for prevention, given the potential reversibility of all these factors.

Keywords: Falls; Functional disability; Hospitalization; Mortality; Oral health; Physical frailty; Quality of life.

Fig. 1

Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) 2020: flow chart illustrating the number of studies at each stage of the review

Fig. 2

Eleven oral health items associated to the identified four categories (oral health status deterioration; decline in oral motor skills; chewing, swallowing, and saliva disorders; oral pain), related to six adverse health-related outcomes (mortality, physical frailty, functional disability, quality of life, hospitalization, and falls)

Fig. 3

Percentage distribution of the different adverse health-related outcomes in older age investigated in the selected studies

Fig. 4

Doughnut chart for the four categories of oral health items (oral health status deterioration; decline in oral motor skills; chewing, swallowing, and saliva disorders; oral pain), and combined with the corresponding eleven indicators of oral health and relative metrics for each of the heath-related adverse outcomes: mortality (a), physical frailty (b), functional disability (c); quality of life (d), hospitalization (e), and falls (f)

Fig. 4

Doughnut chart for the four categories of oral health items (oral health status deterioration; decline in oral motor skills; chewing, swallowing, and saliva disorders; oral pain), and combined with the corresponding eleven indicators of oral health and relative metrics for each of the heath-related adverse outcomes: mortality (a), physical frailty (b), functional disability (c); quality of life (d), hospitalization (e), and falls (f)

Fig. 5

Methodological quality assessment within studies (panel A) and overall quality assessment across studies (panel B)

Fig. 5

Methodological quality assessment within studies (panel A) and overall quality assessment across studies (panel B)