Assessment of potential clinical cascade between oral hypofunction and physical frailty: Covariance structure analysis in a cross-sectional study

Comparative Analysis of Frailty Risk and Associated Factors: Community-Based vs. Open Recruitment Groups

BACKGROUND

Frailty leads to vulnerability to stress, impaired daily functioning, and an increased need for care. Frailty is considered reversible, and it is crucial to detect the risk of frailty early and investigate factors that may delay its progression.

OBJECTIVES

To identify tests that can explain frailty risk and compare the situation of local residents with and without frailty support.

METHODS

Participants were recruited in two ways: through public advertisements in Akita City (open recruitment group) and through invites from frailty supporters in their immediate communities (community-based group). We examined the differences in frailty risk and oral, motor, and social functions between the two groups and identified factors associated with frailty risk in both groups.

RESULTS

The community-based group exhibited a lower risk of frailty than the open recruitment group despite having more older members on average. Additionally, the community-based group demonstrated better social functioning than the open-recruitment group. Furthermore, factors such as oral diadochokinesis (ODK), one-leg stand test (OLS), and grip strength (GS) showed significant association with frailty risk.

CONCLUSION

The ODK, OLS, and GS were identified as factors explaining frailty risk, and Frailty Supporters may reduce the risk of frailty.

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 hypofunction and general health: a systematic review

BACKGROUND

Oral hypofunction comprises 7 oral function conditions, including mastication, swallowing, pronouncing, oral hygiene, and oral dryness. However, it remains unresolved whether having oral hypofunction and each individual condition adversely affect general health. This study aimed to investigate the association between oral hypofunction and general health, encompassing physical, psychological, and social dimensions.

METHODS

Oral hypofunction was diagnosed following the criteria proposed by the 2016 Japan Society of Gerodontology, comprising 7 oral function conditions. Oral hypofunction was diagnosed when at least 3 conditions presented. The selected studies eligible for reviewing were based on the PI(E)CO criteria: P (population), adult and older adults; I/E (intervention/exposure), having oral hypofunction by considering overall and individual 7 oral function conditions; C (comparator), not having oral hypofunction; O (outcome), the general health status, encompassing physical, psychological, and social dimensions. Electronic search limited to English articles was performed through PubMed, Scopus, and Cochrane Database of Systematic Reviews databases from January 2016 to June 2023. The included studies were assessed for quaility and risk of bias using the modified Newcastle-Ottawa scale. Qualitative analyses were performed on the general outcome, and having oral hypofunction considering overall and individual oral function conditions.

RESULTS

Ten studies were included in the final syntheses. One was a prospective cohort, one was a case-control, and the others were cross-sectional studies. All included studies were high quality. General health outcomes were mostly frailty, sarcopenia, and malnutrition, whereas mild cognitive impairment,social withdrawal, and gastric cancer prognosis were identified in one of the included studies. The association between general health and having oral hypofunction was stronger than when considering an individual condition. The health outcomes were predominantly associated with mastication and swallowing, whereas their relationships with oral hygiene and dryness were less likely to be reported.

CONCLUSIONS

The present review found an association between the presence of oral hypofunction and impaired general health. However, the specific impact on individual physical, psychological, and social dimensions cannot be distinctly delineated. Further prospective studies are required to clarify the causal-effect relationship between oral and general health.

Prevalence of frailty and its association with oral hypofunction in older adults: a gender perspective

BACKGROUND

Previous studies have indicated an association between oral hypofunction and frailty in community-dwelling older adults. However, this issue has not been evaluated in institutionalized older patients. We aimed to determine the prevalence of physical frailty in this particularly vulnerable group and evaluate its association with oral hypofunction, analyzing possible differences by gender.

METHODS

This cross-sectional study was conducted in private and public care homes in Guayaquil (Ecuador) from January 2018 until December 2019. Participants were classified as robust, pre-frail, and frail according to the Fried's frailty phenotype. Oral hypofunction was defined as the presence of at least three positive items in the following list: poor oral hygiene, oral dryness, reduced occlusal force, decreased masticatory function, and deterioration of swallowing function. The relationships between frailty and oral hypofunction were analyzed using logistic regression models for the whole sample and stratified by gender. Statistical analyses were performed using STATA 15.0 software (Stata Corp. LP, College Station, TX, USA).

RESULTS

Among the 589 participants analyzed (65% women), the median age was 72 years (interquartile range: 66-82). Pre-frailty and frailty were presented in 66.7% and 28.9% of them respectively. Weakness was the most frequent item (84.6%). There was a significant relationship between frailty and oral hypofunction in women. In the overall sample, the frequency of frailty was 2.06 times higher (95% CI 1.30-3.29) in patients with oral hypofunction, and this association was maintained in women (ORa: 2.18; 95% CI 1.21-3.94). Reduced occlusal force and decreased swallowing function were items significantly associated with the presence of frailty (ORa: 1.95; 95% CI 1.18-3.22 and ORa: 2.11; 95% CI 1.39-3.19, respectively).

CONCLUSION

The prevalence of frailty and pre-frailty was high among institutionalized older people and was associated with the presence of hypofunction, especially in women. Decreased swallowing function was the most strongly item associated with frailty.

Association between oral function and physical pre-frailty in community-dwelling older people: a cross-sectional study

BACKGROUND

Few studies have examined the relationship between oral functions and the physical pre-frailty status, classified using physical function tests. This cross-sectional study aimed to clarify this association among community-dwelling older people from the Itoshima Frail Study in Itoshima Fukuoka Prefecture.

METHODS

Of the 1,555 individuals invited to join the study, 381 (188 males and 193 females) enrolled. Their physical pre-frailty was assessed with a classification system consisting of two physical indicators (fatigue and unintentional weight loss, determined with a questionnaire), two functional components (declined walking speed and muscle weakness, determined using a body function measuring instrument), and declined physical activity (examined using a triaxial accelerometer). Subsequently, the individuals were classified into three groups: robust, pre-frailty, and frailty. Along with the number of teeth remaining, oral functions, such as masticatory performance, tongue pressure strength, and oral diadochokinesis (ODK), were examined. Data regarding social activity and exercise habits were collected, and the individuals' body compositions were measured. Odds ratios (ORs) and 95% confidence intervals (CIs) for the physical pre-frailty were calculated using logistic regression models.

RESULTS

In this study, 126 (33%) participants presented with physical pre-frailty. The participants in the robust group were younger, had stronger maximum handgrip strength, and walked faster than those in the physical pre-frailty group (p < 0.001). The robust group presented with better oral functions (masticatory performance, p = 0.015; oral ODK /ta/, p = 0.004). The physical pre-frailty status was significantly associated with age (OR, 1.111; 95% CI, 1.048-1.178; p < 0.001), masticatory performance (OR, 0.819; 95% CI, 0.680-0.986; p = 0.035), low ODK/ta/ (OR, 1.864; 95% CI, 1.069-3.250; p = 0.028), and low social activity (OR, 2.273; 95% CI, 1.308-3.951; p = 0.004).

CONCLUSION

This study indicated that older people with higher age, lower anterior tongue movement, lower masticatory performance, and lower social activity are positively associated with physical pre-frailty.

Associations of general health conditions with masticatory performance and maximum bite force in older adults: A systematic review of cross-sectional studies

OBJECTIVES

To give an overview of the current evidence on the associations of general health conditions with masticatory performance and maximum bite force in older adults.

DATA/SOURCES

Three electronic databases (Medline via PubMed, Embase via Ovid and CINAHL Plus via EBSCOhost) were searched up to September 2021 for cross-sectional studies on general health conditions and masticatory performance or maximum bite force in older adults. Methodological quality of the included studies was independently evaluated based on Joanna Briggs Institute critical appraisal checklist for analytical cross-sectional studies. Data on the associations between general health conditions and masticatory performance or maximum bite force were extracted.

STUDY SELECTION

Of the 5133 records identified, 39 studies (43 articles) were included in this review. Significant negative associations were found between masticatory performance and stroke, sarcopenia, amyotrophic lateral sclerosis, chronic obstructive pulmonary disease, dyspepsia, dysphagia, anorexia, and carotid atherosclerosis. Significant negative association was found between maximum bite force and sarcopenia. There were equivocal results on the association between masticatory performance and diabetes mellitus, and between maximum bite force and stroke, and amyotrophic lateral sclerosis. There was no significant association between masticatory performance and metabolic syndrome, and between maximum bite force and progress of Parkinson's disease. Most studies revealed positive associations of physical function with masticatory performance and maximum bite force.

CONCLUSIONS

Negative associations between masticatory function of older adults and presence of several systemic diseases have been reported in a number of studies while there are positive associations between masticatory function and some physical function indicators.

CLINICAL SIGNIFICANCE

This study provides valuable information on the association of masticatory function with general health, which draws clinicians' attention to the masticatory function of older adults who suffer from certain systemic diseases or physical dysfunction, and to the need to improve their masticatory ability to achieve healthy aging.

Regular Oral Health Management Improved Oral Function of Outpatients with Oral Hypofunction in Dental Hospital: A Longitudinal Study

This longitudinal study aimed to clarify the impact of regular oral health management for oral hypofunction on the oral function of older dental outpatients. The 68 participants enrolled in this study were older dental outpatients (mean age 78.5 ± 8.1 years). According to the number of declined oral examinations after the first exam, participants were assigned to the oral hypofunction group (Hypo group, ≥3), receiving regular oral health management with a leaflet at the dental clinic, or the pre-oral hypofunction group (Pre-hypo group, ≤2), which served as a control. At the second oral examination, after approximately 6 months to 1 year, the Hypo group showed significant improvement in the tongue-lip motor function (Oral diadochokinesis, ODK) /pa/, /ta/, and masticatory function, while the Pre-hypo group showed significant worsening in oral hygiene and oral wetness. Temporal changes in ODK /pa/, /ta/, and the number of declined examination items were significantly different between the groups. Multiple analysis revealed that the number of improved oral examination items were associated with presence of regular oral health management after adjusting for age, sex, number of visits, measuring period, and dental treatment. Regular comprehensive oral health management for oral hypofunction improves and maintains oral function among older dental outpatients.

Impact of oral health guidance on the tongue-lip motor function of outpatients at a dental hospital

Objective

To clarify the effect of oral health guidance on tongue‐lip motor function in the outpatients visiting the Showa University Dental Hospital (Tokyo, Japan).

Background

The management of the oral function of older people visiting a dental hospital is important. Previous studies have revealed that tongue‐lip motor function is easy to improve. However, the impact of oral health guidance on tongue‐lip motor function in the outpatients of dental hospital requires further elucidation.

Materials and Methods

The participants (n = 35) included patients who were diagnosed with low tongue‐lip motor function on evaluation by oral diadochokinesis (ODK) at the outpatient clinic. They underwent a second examination approximately 6‐12 months later. Their demographic characteristics were recorded. Oral health guidance was provided through an educational leaflet on oral hypofunction when the participants visited the clinic. It included content on tongue twisters, voice training and a range of movement and muscle training of the tongue and lip.

Results

Following oral health guidance on tongue‐lip motor function, the ODK values changed from 5.6 at the first examination to 6.0 at the second for /pa/, from 5.6 to 5.8 for /ta/ and from 5.2 to 5.4 for /ka/. This improvement was not significantly associated with age, sex, measurement period or number of visits.

Conclusion

The findings of this longitudinal study suggested that oral health guidance using an oral hypofunction educational leaflet may be effective in improving the tongue‐lip motor function of outpatients who had low tongue‐lip motor function, regardless of the measurement period or the number of visits to the dental hospital.

Reliability of Screening Methods to Diagnose Oral Dryness and Evaluate Saliva Secretion

In this study, we evaluated the reliability and reproducibility of widely implemented salivary flow rate and oral dryness tests. In experiment 1, twenty young and healthy Japanese participants volunteered to participate. For each participant, the oral moisture (OM) level, unstimulated whole saliva volume (U-WSV), and stimulated whole saliva volume (S-WSV) were measured at the same time on two separate days. In experiment 2, twenty-seven patients who were over 65 years of age volunteered to participate. The OM level and U-WSV were measured at the same time on two separate days. In Experiment 1, the intra-class correlation coefficients (ICCs) corresponding to the S-WSV, U-WSV, and OM level were 0.23, 0.28, and 0.16, respectively, for the young participants. In Experiment 2, the ICCs corresponding to the U-WSV/spitting and OM level were 0.83 and 0.12, respectively, for the older participants. The results of Bland–Altman analysis confirmed the absence of systematic error, with the exception of the OM level results in Experiment 2, which indicated systematic bias. In conclusion, we believe that there is currently no consistent and reliable screening test for assessing salivary flow rate and oral dryness, although the spitting test was determined to be highly reliable.