Association between sarcopenia and oral functions in community-dwelling older adults: A cross-sectional study.

BACKGROUND: Few studies have examined the state of oral function in older adults with sarcopenia. We assessed the oral functions of community-dwelling older adults with sarcopenia from multiple perspectives to clarify their potentially low oral function. METHODS: A total of 1517 (86.2%; 990 women, 527 men; mean age 76.1 ± 7.6 years) participants were included in this study. Grip strength, gait speed and skeletal muscle mass index were assessed, and sarcopenia was evaluated according to the criteria of the Asian Working Group for Sarcopenia 2019. The degree of tongue coating, oral moisture, occlusal force, tongue-lip motor function, tongue pressure, masticatory function and swallowing function were assessed. The criteria for oral hypofunction (a disease that is a combination of multiple low oral functions) were used to assess oral function. Statistical analyses were performed using Kolmogorov-Smirnov test, unpaired t-test, Mann-Whitney U test, χ2 test, and univariate and multivariable logistic regression analyses, with each oral function as the dependent variable and sarcopenia as one of the independent variables. The significance level was set at P < 0.05. RESULTS: The prevalence rates of sarcopenia and severe sarcopenia were 14.2% and 3.8%, respectively. The prevalence of oral hypofunction was 39.9%. Compared with the robust group, the sarcopenia and severe sarcopenia groups tended to have a higher frequency of the following components (all P < 0.01): low occlusal force, low tongue-lip motor function, low tongue pressure, low masticatory function, low swallowing function and oral hypofunction. Univariate logistic regression analysis showed that sarcopenia was associated with low occlusal force, low tongue-lip motor function, low tongue pressure, low masticatory function, low swallowing function and oral hypofunction. The odds ratios and 95% confidence intervals of sarcopenia for each oral function were 2.62 [2.00, 3.43], 2.21 [1.69, 2.89], 3.66 [2.79, 4.81], 3.23 [2.46, 4.25], 1.66 [1.26, 2.20] and 3.59 [2.72, 4.72], respectively. Multivariable logistic regression analysis showed that sarcopenia was associated with low occlusal force (1.63 [1.10, 2.40]), low tongue pressure (2.28 [1.65, 3.15]), low masticatory function, (1.94 [1.27, 2.97]), low swallowing function (1.64 [1.17, 2.28]) and oral hypofunction (2.17 [1.52, 3.09]). CONCLUSIONS: This study demonstrated that multiple aspects of oral function were low among community-dwelling older adults with sarcopenia. The potential decline in oral functions in older adults with sarcopenia may have been overlooked until now. This study indicates the need for dental perspectives in intervening with older adults with sarcopenia and the need to encourage them to see dental professionals.

Impact of number of functional teeth on independence of Japanese older adults.

AIM: To examine the relationship between the number of present and functional teeth at baseline and future incidence of loss of independence. METHODS: Participants were community-dwelling older individuals who participated in a comprehensive geriatric health examination conducted in Kusatsu town, Japan, between 2009 and 2015. The primary endpoint was the incidence of loss of independence among participants, defined as the first certification of long-term care insurance in Japan. The numbers of present and functional teeth at baseline were determined via an oral examination. Demographics, clinical variables (e.g., history of chronic diseases and psychosocial factors), blood nutritional markers, physical functions, and perceived masticatory function were assessed. RESULTS: This study included 1121 individuals, and 205 individuals suffered from loss of independence during the follow-up period. Kaplan-Meier estimates of loss of independence for participants with smaller numbers of present and functional teeth were significantly greater than for those with larger numbers of teeth. Cox proportional hazard analyses indicated that a smaller number of present teeth was not a significant risk factor after adjusting for demographic characteristics. However, the number of functional teeth was a significant risk factor after the adjustment (hazard ratio: 1.975 [1.168-3.340]). Additionally, higher hazard ratios were observed in other adjusted models, but they were not statistically significant. CONCLUSIONS: The number of functional teeth may be more closely related to the future incidence of loss of independence than the number of present teeth. This novel finding suggests that prosthodontic rehabilitation for tooth loss possibly prevents the future incidence of this life-event. Geriatr Gerontol Int 2022; 22: 1032-1039.

Prevalence, overlap, and interrelationships of physical, cognitive, psychological, and social frailty among community-dwelling older people in Japan.

Background The aim of this study is to explore the prevalence and overlap of physical, cognitive, psychological, and social frailty and their negative-interrelationships. Methods We conducted a survey of people aged ≥75 years in the region with the oldest population in Japan. Frailty was divided into physical, cognitive, psychological, and social frailty, which were evaluated with the Japanese version of the Cardiovascular Health Study (J-CHS) criteria, J-CHS and the Japanese version of the Montreal Cognitive Assessment, the Geriatric Depression Scale-15 and the Lubben Social Network Scale, respectively. Results Of the 268 participants (aged 81.5 ± 4.5 years), 48.1% and 8.6% had physical prefrailty and frailty; 68.3%, 13.0%, and 5.2% had mild cognitive impairment, dementia, and cognitive frailty; 25.7% and 5.2% had depressive mood and depression as psychological frailty; and 7.8% had social frailty, respectively. Path analysis showed that social frailty was associated with psychological frailty. Psychological frailty was associated with physical frailty. Physical frailty was associated with cognitive frailty. Multiple logistic regression analysis showed that independent determinants of physical robustness were female sex, age, and psychological robustness (odds ratio (OR) = 2.166, 0.831, 3.625, respectively). Determinants of cognitive robustness were age and psychological robustness (OR = 0.837, 7.079). Determinants of psychological robustness were physical, cognitive, and social robustness (OR = 3.759, 6.829, 5.037), and the determinant of social robustness was psychological robustness (OR = 4.489), respectively. Conclusions We demonstrated the prevalence, overlap, and interrelationships of different types of frailty and clarified the factors that may help to reduce frailty.

Relationship between Oral Hypofunction and Sarcopenia in Community-Dwelling Older Adults: The Otassha Study.

Oral hypofunction, resulting from a combined decrease in multiple oral functions, may affect systemic-condition deterioration; however, few studies have examined the association between oral hypofunction and general health among older adults. In this cross-sectional study, we examined the relationship between oral hypofunction and sarcopenia in community-dwelling older adults. We included 878 adults (268 men and 610 women, mean age 76.5 ± 8.3 years). Tongue coating index, oral moisture, occlusal force, oral diadochokinesis (/pa/,/ta/,/ka/), tongue pressure, mas-ticatory function, and swallowing function were evaluated as indicators of oral hypofunction. Grip strength, gait speed, and skeletal muscle mass index were measured as diagnostic sarcopenia parameters. The association between oral hypofunction and sarcopenia was examined via logistic regression using sarcopenia as the dependent variable. Oral hypofunction prevalence was 50.5% overall, 40.3% in men, and 54.9% in women. The prevalence of sarcopenia was 18.6% overall, 9.7% in men, and 22.5% in women. A logistic regression showed oral hypofunction, age, body mass index, higher-level functional capacity, and serum albumin level were significantly associated with sarcopenia. Sarcopenia occurred at an increased frequency in patients diagnosed with oral hypofunction (odds ratio: 1.59, 95% confidence interval: 1.02-2.47); accordingly, oral hypofunction appears to be significantly associated with sarcopenia.

[The oral function of community-dwelling older adults complaining of an oral function deterioration: An examination using the oral function-related items of the Questionnaire for Latter-stage Elderly People].

AIM: The oral function-related items of the newly developed "Questionnaire for Latter-stage Elderly People" are based on two items of the Kihon checklist assessing the masticatory and swallowing functions. In this study, we estimated the questionnaire's application rate and investigated the oral function of the respondents. METHODS: Included were 699 older adults (274 men/425 women, average age, 73.4±6.6 years old). Those who responded positively to the related items were considered to have decreased swallowing and masticatory functions. The specific oral function was assessed based on the number of present and functional teeth; oral hygiene; oral moisture; occlusal force; oral diadochokinesis /pa/, /ta/, /ka/; tongue pressure; mixing ability; shearing ability; and Eating Assessment Tool (EAT)-10 (reference, score ≥3). RESULTS: The rates of decreased masticatory and swallowing functions were 21.5% and 26.6%, respectively, while 7.4% of participants had both. Those with a decreased masticatory function showed fewer present teeth; a lower occlusal force, oral diadochokinesis /pa/, mixing ability, shearing ability, and higher EAT-10 scores.Those with a decreased swallowing function only had higher EAT-10 scores. In the early- and latter-stage elderly, the decreased masticatory function rates were 15.6% and 29.4%, respectively, the decreased swallowing function rates were 27.8% and 25.0%, respectively, and the rates of both decreased masticatory and swallowing functions were 6.0% and 9.5%, respectively. CONCLUSION: The older adults who responded positively to the related questionnaire items, especially for items related to masticatory function, had a decreased oral function in multiple respects. The items related to the oral function in the Questionnaire for Latter-stage Elderly People are considered useful for identifying older adults with a decreased oral function.

Distribution of lip-seal strength and its relation to oral motor functions.

OBJECTIVES: Lip-seal strength, which represents the muscle strength of the lips, appears to chiefly contribute to mastication and pronunciation. However, the functional characteristics of lip-seal strength in adults are still undefined. The present study aimed to understand not only the distribution of lip-seal strength in adult men and women but also the effect of age on this strength and identify oral motor functions correlated with lip-seal strength. MATERIALS AND METHODS: The subjects included 339 participants (men: 170, age 39.2 ± 18.2 years; women: 169, age 43.1 ± 19.7 years). Oral motor function was evaluated for lip-seal strength, oral diadochokinesis (ODK), tongue pressure, occlusal force, and masticatory performance. Statistical analyses included the Shapiro-Wilk, Mann-Whitney U, and Jonckheere-Terpstra tests, in addition to the Spearman's correlation analysis and curvilinear regression analysis. RESULTS: Lip-seal strength did not have a normal distribution (p < 0.001). The mean ± standard deviation and median (first quartile, third quartile) of lip-seal strength were 11.2 ± 3.4 and 10.9 (8.7, 13.2)N for the whole sample, 12.3 ± 3.4 and 11.9 (9.4, 14.4)N for men, and 10.2 ± 3.0 and 9.9 (8.0, 12.0)N for women. A significant difference was observed in lip-seal strength between men and women (p < 0.001). Oral motor functions showed a marked correlation with lip-seal strength, including tongue pressure, occlusal force, and masticatory performance and ODK (/pa/ and /ta/), tongue pressure, and masticatory ability in men and women, respectively. In women, lip-seal strength declined with increase in age. CONCLUSIONS: Lip-seal strength was non-normally distributed in both men and women, and lip-seal strength was affected by age only in women. Lip-seal strength and multiple oral motor functions were significantly correlated. Because the indicators of perioral muscle strength and performance were correlated with lip-seal strength, lip-seal strength may also partially reflect the condition of the perioral muscles.

[Relationship between the rate of a decreased oral function and the nutrient intake in community-dwelling older persons: An examination using oral function-related items in a questionnaire for latter-stage elderly people].

AIM: To determine the rate of a decreased oral function using questions from the Kihon checklist corresponding to the Questionnaire for Latter-stage Elderly People and to clarify nutrient intake in older persons. METHODS: This study targeted 511 older people (217 men, 294 women, average age 73.1±5.6 years old). Their oral function was evaluated using questions on the masticatory function and swallowing function from the Kihon checklist, corresponding to questions on the oral function in the Questionnaire for Latter-stage Elderly People. Participants who had at least one symptom measured were defined as the applicable group (AG). In addition, to evaluate the nutrient intake of the participants, interviews were conducted using the Food Frequency Questionnaire Based on Food Groups. RESULTS: The rate of inclusion in the AG was 32.9% for the total sample, 28.2% for early-stage elderly people, and 40.1% for latter-stage elderly people. The AG rates did not differ significantly between men and women. For latter-stage elderly people, the protein-energy ratio and intakes of total energy, protein, pantothenic acid, folic acid, vitamin B6, niacin, vitamin K, copper, zinc, phosphorus, magnesium, potassium, and total dietary fiber were significantly lower in the AG than in the non-AG. CONCLUSION: The evaluation of placement in the AG through questions on the oral function from the Kihon checklist corresponding to the Questionnaire for Latter-stage Elderly People demonstrated that the rate of a decreased oral function was higher in latter-stage elderly people than in early-stage elderly people. In addition, the latter-stage elderly people in the AG had a lower nutrient intake.

A comparison of colorimetric and visual methods for the assessment of masticatory performance with color-changeable chewing gum in older persons.

BACKGROUND/PURPOSE: Color-changeable chewing gum is used for the evaluation of masticatory performance. However, it is currently unclear whether colorimetric and visual assessment methods yield consistent results. This study aimed to clarify the consistency between colorimetric and visual methods used for the evaluation of color changes in color-changeable chewing gum. MATERIALS AND METHODS: The sample comprised 644 older persons (mean age, 75.4 ± 6.4 years). The chewing gum was masticated 60 times at the participant's own chewing rate and then expectorated. The color of the chewing gum was evaluated with the ΔE values and a∗ values, measured using a colorimeter, and the 10 Color Shades (10CSh) and 5 Color Scales (5CSc), using visual evaluation. Spearman's correlation analysis was performed to examine the correlation between the results obtained by the four methods. The significance level was set at α = 0.05. RESULTS: The ΔE values, a∗ values, 10CSh scores, and 5CSc scores were all significantly correlated. The highest correlation coefficient (0.979) was between the ΔE values and a∗ values. The lowest correlation coefficient (0.847) was between the a∗ values and 5CSc scores. Decreased masticatory performance was observed with increased age. CONCLUSION: Significant correlations were found for all four methods used in the assessment of masticatory performance with color-changeable chewing gum. While visually based assessments are valid, colorimetric methods are more sensitive to smaller changes in masticatory performance.

Association between oral, social, and physical frailty in community-dwelling older adults.

OBJECTIVES: Oral frailty (OF) has been shown to be a predictor of disability. Therefore, it is important to be able to identify factors associated with OF in order to prevent long-term dependence. The purpose of this study was to clarify the relationships between OF, social frailty (SF), and physical frailty (PF) in community-dwelling older adults, with the overarching aim of informing the future development of effective measures to prevent frailty. METHODS: Oral, physical, and social function, nutritional and psychological status, and medical history were examined in 682 community-dwelling individuals (267 men, 415 women) aged ≥ 65 years. Ordinal logistic regression analysis with SF and PF as independent variables was performed with pass analysis to determine the relationship between the different types of frailty. RESULTS: Logistic regression analysis revealed significant associations between OF and decline in social function, physical function, and nutritional status, and an increase in the number of medications used. Path analysis showed that SF was directly related to OF and that OF and SF were directly related to PF. CONCLUSIONS: These findings suggest that a decline in social function may directly influence a decline in oral and physical function. The results of this study provide initial evidence, that may guide the future development of measures that aim to prevent and manage OF.

Number of functional teeth more strongly predicts all-cause mortality than number of present teeth in Japanese older adults.

AIM: Previous studies on the association between intraoral conditions and mortality in community-dwelling older individuals reported that fewer present teeth (PT) are significant risk factors for mortality. However, how the number of PT relative to the number of functional teeth (FT), including both present and rehabilitated teeth, influences mortality has not been investigated fully. This study examined the impact of the number of FT on mortality among community-dwelling Japanese older adults. METHODS: This study was a retrospective, observational and population-based follow-up study, which examined 1188 older individuals who participated in an annual geriatric health examination from 2009 to 2015. The average follow-up period was 1697.0 ± 774.5 days. The primary outcome was all-cause mortality at follow-up. The numbers of PT and FT of each participant were counted during an oral examination. In addition, demographics, clinical variables, blood nutrient markers, physical functions and perceived masticatory function were measured. RESULTS: Kaplan-Meier analysis, followed by a log-rank test, revealed that fewer PT (P < 0.001) and FT (P = 0.002) were significantly associated with a reduced survival rate. Cox's proportional hazard analysis indicated that the number of FT, but not the number of PT, was a significant independent mortality risk factor after adjusting for demographics, clinical variables, nutrient markers and physical functioning (P = 0.036, hazard ratio: 2.089). CONCLUSIONS: Current results suggest that the number of FT more strongly predicts all-cause mortality than the number of PT among community-dwelling older adults. Further studies are necessary to consider the confounding of socioeconomic status and disability status. Geriatr Gerontol Int 2020; ••: ••-••.

Rate of oral frailty and oral hypofunction in rural community-dwelling older Japanese individuals.

OBJECTIVE: To clarify the rate of oral frailty and oral hypofunction in rural community-dwelling older adults in Japan. BACKGROUND: Recently, the oral function of Japanese older adults has been evaluated multilaterally based on two concepts: oral frailty and oral hypofunction. Oral frailty is defined as a decrease in the oral function accompanied by a decrease in mental and physical functions. Oral hypofunction is a disease where the oral function is comprehensively decreased. However, their rates have not yet been elucidated. MATERIALS AND METHODS: Oral frailty and oral hypofunction were evaluated in 679 older adults from rural areas. To investigate the differences in occurrence rates due to the evaluation methods, one of the subordinate symptoms of oral hypofunction, the reduced occlusal force, was evaluated based on both the occlusal force (main method) and the number of teeth (alternative method). RESULTS: The rate of oral frailty was 22.3% in men and 22.7% in women. The rate of oral hypofunction was 39.0% in men and 46.9% in women. The overall rate of oral hypofunction was 43.6% when the reduced occlusal force of oral hypofunction was evaluated using the main method and 46.4% when evaluated using the alternative method. The proportion of participants with decreased occlusal force, the number of present teeth, oral diadochokinesis, tongue pressure and masticatory performance increased with age in both men and women. CONCLUSION: Among rural community-dwelling older adults, the rate of oral frailty was 22.5% and that of oral hypofunction was 43.6%.

Factors associated with masticatory performance in community-dwelling older adults: A cross-sectional study.

BACKGROUND: Decreased masticatory performance leads to deterioration of overall health among older adults. However, maintaining and improving masticatory performance in ways other than maintenance of natural teeth and appropriate prosthodontic treatment remains unclear. If the factors related to the mixing and shearing abilities for masticatory performance are clarified, it may be possible to maintain and improve the masticatory performance of older adults. We aimed to clarify the association among mixing ability, shearing ability, and masticatory performance-related factors. METHODS: Of the 707 community-dwelling older adults in Kusatsu Town, Japan, 344 who had been treated for any dental defects were enrolled in this study. Masticatory performance was evaluated on the basis of mixing ability and shearing ability. The number of natural teeth and artificial teeth, occlusal force, tongue pressure, and oral diadochokinesis /ta/ were measured as masticatory performance-related factors. Their relationship with mixing ability, shearing ability, and masticatory performance-related factors was examined by means of Spearman rank correlation coefficient and path analysis. RESULTS: Among masticatory performance-related factors, the number of natural teeth, occlusal force, and tongue pressure were directly associated with both mixing ability and shearing ability. Moreover, mixing ability was also directly associated with shearing ability. CONCLUSIONS: Tongue pressure, which can be improved by means of training, is a masticatory performance-related factor associated with both mixing and shearing abilities. PRACTICAL IMPLICATIONS: Training for tongue pressure after proper prosthetic treatment may provide an effective means of maintaining and improving masticatory performance in older adults.

Intra- and inter-investigator reliabilities of oral moisture measured using an oral moisture-checking device.

BACKGROUND: Oral mucosal moisture determined using oral moisture-checking devices is used as a mouth dryness evaluation method. Such devices are capable of evaluating the state of mouth dryness in a simple manner and have applicability in a wide range of subjects; however, their intra- and inter-investigator reliabilities have not yet been clarified. OBJECTIVE: This study aims to investigate the intra- and inter-investigator reliabilities of measuring oral moisture using an oral moisture-checking device for a wide range of age groups. METHODS: Intra- and inter-investigator reliabilities were investigated in 28 young subjects and 19 older subjects aged ≥65 years. Three trained investigators independently measured oral mucosal moisture values using an oral moisture-checking device. Intra-investigator reliability was assessed using the coefficient of variation (CV) and intraclass correlation coefficient (ICC) (1.1), and inter-investigator reliability was assessed using ICC (2.1). RESULTS: Mean CV was 0.015 and 0.016, mean ICC (1.1) was 0.806 and 0.877, and ICC (2.1) was 0.873 and 0.829 in the young and older subjects, respectively. CONCLUSION: In young subjects, the mean values of ICC (1.1) and ICC (2.1) of the oral moisture-checking device were 0.806 and 0.873, respectively, whereas in older subjects, these values were 0.877 and 0.829, respectively. Thus, this confirms that the examination of oral mucosal moisture using the oral moisture-checking device has sufficient intra- and inter-investigator reliabilities for a wide range of age groups.

Association between simple evaluation of eating and swallowing function and mortality among patients with advanced dementia in nursing homes: 1-year prospective cohort study.

BACKGROUND: A simple and predictable method of evaluating eating and swallowing has not been yet established; thus, it is difficult to implement advance care planning according to deterioration in this function. This study aimed to clarify the association between a simple evaluation of eating and swallowing function and 1-year mortality in advanced dementia patients in nursing homes in Japan. METHODS: The study included 325 residents with advanced dementia. In a baseline survey, we examined medical history, physical function, and eating and swallowing function. We recorded mortality for 1 year from baseline. Kaplan-Meier survival analysis and Cox proportional regression were performed to investigate the association between the simple evaluation of eating and swallowing function and mortality. RESULTS: Statistical analysis included data from 312 of the 325 residents who had completed the baseline survey (7 individuals with non-oral ingestion and 6 who were alive but did not reside in the nursing home 1 year later were excluded). The participants' mean age was 85.2 years, and 79.5 % of participants were female. At the 1-year follow-up, 70 patients had died. According to Cox proportional regression analysis, age, male gender, history of cerebrovascular disorder, poor results of palpation of masseter muscle tension, and modified water swallowing test were significantly associated with 1-year mortality. CONCLUSION: The results of palpation of masseter muscle tension and modified water swallowing test were associated with 1-year mortality. These routine observations can predict mortality, and may thus provide evidence of the opportunity to implement advance care planning.

Validity of a visual scoring method using gummy jelly for evaluating chewing efficiency in a large-scale epidemiological survey.

BACKGROUND: Several methods exist for objectively evaluating chewing efficiency by using gummy jelly. However, the validity of the subjective visual evaluation of chewing efficiency has not been assessed. OBJECTIVE: To verify with an epidemiological study, the validity of a visual scoring method using gummy jelly by testing the relationship between masticatory performance (MP) using a fully automatic measuring system and visual score (VS) using a visual scoring method. METHODS: Community-dwelling elderly individuals (n = 1234) ≥70 years old participated. One evaluator measured VS consecutively after participants chewed the gummy jelly (ie, actual-VS). The chewed jelly was photographed. Two evaluators used the photograph to measure the gummy jelly (ie, photo-VS). To test the validity of both methods, the correlation between actual-VS and MP and between photo-VS and MP were analysed. Inter-rater reliability between the evaluators of photo-VS was analysed. RESULTS: Significant correlations existed between actual-VS and MP and between photo-VS and MP (r = 0.86-0.87; P < 0.001). The intra-class correlation coefficient of the inter-rater reliability for photo-VS was very high (0.93; P < 0.001; 95% confidence interval: 0.877-0.953); however, the distribution of photo-VS deviated slightly from the actual-VS. A large coefficient of variation in the MP for low VSs suggested the influence of incomplete comminution, which was not reflected by the VS, and the accidental swallowing of small pieces during chewing. CONCLUSION: The VS deviated slightly from the MP calculated using a fully automated method; however, the VS can be utilised for epidemiological surveys with numerous participants.

Relationship between mild cognitive decline and oral motor functions in metropolitan community-dwelling older Japanese: The Takashimadaira study.

BACKGROUND: Diminished oral motor function is considered to be a factor influencing cognitive decline, but this association has not been clarified. The aim of the present study was to clarify the association between cognitive and oral motor function in older people with either from normal cognitive function or mild cognitive decline. METHODS: A cross-sectional study was conducted across 1118 older people (445 men, 673 women) aged ≥70 years (mean age, 77.0 ± 4.7 years) who lived in a city of Tokyo Metropolis, Japan. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Older people who had an MMSE score of 23 points or lower were excluded. To investigate the relationship between cognitive and oral motor function, Pearson's correlation, multiple linear regression, and path analysis were performed. RESULTS: Pearson's correlation revealed that, among the oral motor functions assessed, masticatory performance, occlusal force, and tongue pressure were correlated with MMSE score. Multiple linear regression showed that tongue pressure and oral diadochokinesis (ODK) were significantly associated with MMSE score. Path analysis revealed that decreases in tongue pressure and in ODK were directly associated with decreases in MMSE score. Decreases in tongue pressure were also indirectly associated with decreases in MMSE score via decreases in ODK. CONCLUSIONS: Among the oral motor functions assessed, tongue pressure and ODK were associated with cognitive function in older people ranging from those with normal cognitive function to those with mild cognitive decline. Diminished tongue pressure and ODK might thus lead to cognitive decline.