The association between bilateral maximum occlusal force and all-cause mortality among community-dwelling older adults: The Tsurugaya project

Number of teeth and functional disability in community-dwelling older adults

INTRODUCTION

This study determined whether tooth loss was associated with the development of functional disability and estimated the population attributable fraction (PAF) of functional disability due to tooth loss, along with risk factors for functional disability such as physical function and cognitive impairment.

METHODS

The participants were 838 community-dwelling older adults aged ≥70 years living in the Tsurugaya district in Japan in 2003. The exposure variable was the number of remaining teeth (counted by trained dentists). Other variables were age, sex, depressive symptoms, cognitive impairment, educational attainment, physical function and social support. The Cox proportional hazards model was applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of the incidence of functional disability for each risk factor, such as tooth loss. The functional disability PAF due to tooth loss was estimated, and risk factors for functional disability were identified.

RESULTS

In total, 619 (73.9%) participants developed functional disability during follow-up. A multivariable model showed that those with <20 teeth (HR, 1.28; 95% CI, 1.08-1.53) were more likely to develop functional disability than those with 20 teeth or more. PAF estimation for functional disability was shown to have decreasing values in the following order: age, female sex, tooth loss and reduced physical function.

CONCLUSIONS

Tooth loss was associated with the development of functional disability in community-dwelling older Japanese adults. While retaining teeth may be a potential strategy for avoiding functional disability, clinical studies on the effect of dental treatment on preventing functional disability are warranted.

The predictive value of masticatory function for adverse health outcomes in older adults: a systematic review

Masticatory function is associated with a variety of health outcomes. The aim of this systematic review is to clarify the predictive value of masticatory function for adverse health outcomes, such as frailty, sarcopenia and malnutrition, in older adults. An online literature search covered articles published in English or Dutch in three databases (PubMed, Embase and CINAHL, last searched November 4th 2022). Inclusion criteria were: an observational study design, focus on adults aged ≥65 years and evaluation of the association between masticatory function and health outcomes. Reviews and articles published before the year 2000 were excluded. Methodological quality and risk of bias were assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies of the U.S. National Institutes of Health. Study population demographics, methods for assessing masticatory function, and the association between masticatory function and adverse health outcomes were extracted. From the 34 included studies, 5 studies had a prospective design, 2 had a retrospective design, and the other 27 studies had cross-sectional design. The majority of the studies were conducted in Japan (74%, n = 26). Twenty studies (59%) used one indicator for masticatory function, the other 41% used two (n = 9) or more (n = 5) indicators. Masticatory function was most frequently assessed with the maximum occlusal force (MOF) (79%, n = 27). The identified health outcomes were clustered into 6 categories: physical parameters and sarcopenia, history of falling, nutritional status, frailty, cognitive function and mortality. Despite the complex and multidimensional character of both masticatory function and most identified adverse health outcomes, some significant associations were reported. Prospective studies showed that reduced masticatory function in older adults is associated with incidence of frailty and frailty progression, cognitive decline and all-cause mortality. Regarding the other identified adverse health outcomes, i.e., physical measures and sarcopenia, history of falling and nutritional status, only cross-sectional studies were available and results were less concordant. As all prospective studies showed that reduced masticatory function in older adults is associated with adverse health outcomes, prevention of decline of masticatory function by adequate oral care may contribute to healthy ageing.

Association between oral health and nutritional status among older patients requiring long-term care who received home-visit dental care

PURPOSE

This study examined the association between oral health and nutritional status among older patients receiving home-visit dental care.

METHODS

This study enrolled 110 older patients (age ≥65 years) requiring long-term care who received home-visit dental care. The oral health indicators evaluated included number of teeth, occlusal support, number of functional teeth, tongue pressure, tongue coating index (TCI), and rinsing ability. Nutritional indicators included skeletal muscle mass index (SMI) and the mini-nutritional assessment short-form (MNA-SF). A multivariate modified Poisson regression analysis (adjusted for age, sex, medical history, care level, and housing type) was used to calculate prevalence ratios and 95% confidence intervals (CIs).

RESULTS

The prevalence ratio for low SMI was not significantly higher for patients with ≥20 teeth than for those with 1-19 or no teeth. Number of teeth was not significantly associated with MNA-SF score. A high TCI score (2.15, 95% CI: 1.07-4.32) and poor rinsing ability (2.32, 95% CI: 1.25-4.30) were significantly associated with low SMI. High TCI scores were associated with low scores in MNA-SF categories (1.25, 95% CI: 1.01-1.55).

CONCLUSION

TCI and rinsing ability, rather than number of teeth, were associated with nutritional status in older patients requiring long-term care.

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

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.

Relationship between occlusal force and endothelial function in community‐dwelling elderly women: A pilot study

Objective

In this study, age, endothelial function as flow‐mediated dilation (FMD), occlusal force, grip strength, and advanced glycation end products (AGEs) were obtained. AGEs were measured as indicators of aging, while grip strength was measured as an indicator of muscle strength. This study aimed to explain the relationship between occlusal force and endothelial function and determine whether occlusal force can be a new indicator in community preventative care projects.

Materials and Methods

In 38 community‐dwelling women (age, 76.7 ± 5.7 years), the occlusal force and grip strength were measured, the endothelial function was evaluated by FMD, and AGEs were obtained. The relationship between occlusal force, measurement items, and factors were investigated independently related to endothelial function.

Results

There were significant correlations between occlusal force and grip strength (r = .54, p < .01). The degree of FMD was significantly associated with occlusal force (r = .60, p < .01) and grip strength (r = .35, p < .05) or increase in AGEs (r = −.37, p < .05). Multiple regression analysis revealed that occlusal force was significantly associated with the degree of FMD (p < .01).

Conclusion

Occlusal force can be an important indicator of endothelial function in the community‐dwelling elderly. This study may help understand the general health of the elderly in communities.

Relationship between maximum occlusal force and gastrointestinal cancer in community-dwelling older Japanese adults

Globally, the cancer burden is expected to increase as populations are ageing. Therefore, cancer prevention among older age groups is important. This prospective cohort study examined the relationship between the number of remaining teeth, maximum occlusal force, and incidence of gastrointestinal cancer in community-dwelling older Japanese individuals using data from the Tsurugaya project; 847 participants were included. The exposure variables were the number of remaining teeth and the maximum occlusal force, with the outcome being the incidence of gastrointestinal cancer. Covariates were age, sex, medical history, smoking, alcohol consumption, educational attainment, and physical function. The Cox proportional hazard model was used to examine the relationship between the number of remaining teeth, maximum occlusal force, and incidence of gastrointestinal cancer. With a median follow-up of 7.6 years, 63 participants were confirmed to have gastrointestinal cancer. The risk of gastrointestinal cancer was significantly higher in those with an occlusal force lower than the median (hazard ratio, 2.80; 95% confidence interval, 1.54–5.10). No significant risk difference was found according to the number of remaining teeth. Low maximum occlusal force was associated with the incidence of gastrointestinal cancer in community-dwelling older Japanese adults.

Poor oral function is associated with loss of independence or death in functionally independent older adults

AIM

To clarify the association of poor oral function with loss of independence (LOI) or death in functionally independent older adults in the community.

METHODS

We conducted a secondary analysis of data from a prospective cohort study in two municipalities in Japan. We included participants who were older than 65 years of age and had no certification in long-term care at baseline. Poor oral function was evaluated by the Kihon Checklist. Among participants with poor oral function, they were further classified by the degree of quality of life (QOL) impairment due to dysphagia. Main outcome is LOI or death from all cause. The hazard ratio (HR) and 95% confidence of intervals (CIs) were estimated by Cox proportional hazard models adjusted for potential confounders.

RESULTS

Of 1,272 participants, 150 participants (11.8%) had poor oral function. The overall incidence of LOI or death was 10.0% in the participants with poor oral function, while 3.3% in the participants without. Participants with poor oral function were more likely to develop LOI or death than those without (crude HR = 3.17 [95% CIs 1.74-5.78], adjusted HR = 2.30 [95% CIs 1.22-4.36]). 10 participants (0.79%) were classified as poor oral function with QOL impairment, and were more likely to develop LOI or death than those without poor oral function (crude HR = 7.45 [95% CIs 1.80-30.91], adjusted HR = 8.49 [95% CIs 1.88-38.34]).

CONCLUSIONS

Poor oral function was associated with higher risk of LOI or death in functionally independent older adults in the community.