Association of the number of remaining teeth with kidney function in community-dwelling healthy older adults: a cross-sectional study.

Objectives: Although a few studies have investigated the relationship between kidney and oral function (number of remaining teeth), their results remain inconclusive. Therefore, this study aimed to investigate the relationship between kidney function and oral health in community-dwelling healthy elderlies and examine the factors associated with kidney function. Materials and Methods: We used cross-sectional data from the Shimane prefecture cohort recruited by the Center for Community-Based Health Research and Education in 2019. We collected clinical data on dental status, background factors and kidney function (estimated glomerular filtration rate [eGFR], mL/min/1.73 m2 and creatinine levels, mg/dL). Results: The study enrolled 481 participants, whose mean age was 66.7±7.4 years, and 223 (46.4%) participants were men. Multivariate analysis revealed significant correlations between eGFR (B=0.17, P=0.04), creatinine (B=-0.54, P<0.01), and the number of remaining teeth. The number of remaining teeth was associated with creatinine and eGFR, which are indicators of kidney function. Conclusion: This study suggests that preserving the teeth may prevent decline in kidney function. Dental professionals should provide instructions and professional care to reduce the risk of systemic diseases such as kidney dysfunction.

Changes in masticatory performance and the new onset of diabetes mellitus in older adults: a 5-year longitudinal study.

Objective: Although masticatory performance is affected by age-related reduction in number of teeth (or treatment), the relationship between longitudinal changes in masticatory performance and diabetes mellitus is unknown. This longitudinal study investigated the association between changes in masticatory performance and new-onset diabetes mellitus among community-dwelling Japanese older adults. Methods: The data of 214 older adults living in Ohnan Town, Shimane, Japan, who participated in two surveys conducted between 2012 and 2017 were analyzed. Diabetes mellitus was defined as a hemoglobin A1c level ≥ 6.5% or self-reported diabetes mellitus. The masticatory performance (measured by number of gummy jelly pieces collected after chewing) was evaluated by dental hygienists. Masticatory performance was categorized into two groups (high or low) based on the median in each survey; further, four groups (Group A: remained consistently high, Group B: changed from low to high, Group C: remained consistently low, Group D: changed from high to low) were used to determine longitudinal changes in masticatory performance. Logistic regression was used to analyze the association between changes in masticatory performance and new-onset diabetes mellitus. Results: Overall, 10.3% of participants had diabetes mellitus at the follow-up survey. Multivariate analysis showed that Group D (odds ratio 8.69, 95% confidence interval 1.98-38.22) was positively associated with the development of diabetes mellitus compared with Group A after adjusting for sex, age, body mass index, alcohol consumption, physical activity, and eating speed. Conclusions: Deteriorating masticatory performance for 5 years may cause diabetes mellitus among older adults.

Fast Eating Speed Could Be Associated with HbA1c and Salt Intake Even after Adjusting for Oral Health Status: A Cross-Sectional Study.

This study aimed to examine the relationship between eating speed and hemoglobin A1c (HbA1c), considering the number of teeth, using cross-sectional health examination data from community-dwelling older individuals in Japan. We used data from the Center for Community-Based Healthcare Research and Education Study in 2019. We collected data on gender, age, body mass index, blood test results, Salt intake, bone mineral density, body fat percentage, muscle mass, basal metabolic rate, number of teeth, and lifestyle information. Eating speed was evaluated subjectively as fast, normal, or slow. Overall, 702 participants were enrolled in the study and 481 participants were analyzed. Multivariate logistic regression analysis revealed a significant association between fast eating speed and being a male (odds ratio [95% confidence interval]: 2.15 [1.02-4.53]), HbA1c (1.60 [1.17-2.19]), salt intake (1.11 [1.01-1.22]), muscle mass (1.05 [1.00-1.09]), and enough sleep (1.60 [1.03-2.50]). Fast eating may be associated with overall health and lifestyle. The characteristics of fast eaters, after taking oral information into consideration, tended to increase the risk of type 2 diabetes, renal dysfunction, and hypertension. Dental professionals should provide dietary and lifestyle guidance to fast eaters.

Reduced masticatory performance and not using dentures are associated with hypertension in older adults with tooth loss: the Shimane CoHRE study.

The relationship between masticatory performance and hypertension has seldom been studied. The association between hypertension and tooth loss with/without denture use is unclear. This cross-sectional study examined the relationship between hypertension and masticatory performance and whether the relationship between hypertension and the number of teeth varied with denture use among older Japanese adults. Hypertension was defined as a systolic or diastolic blood pressure ≥140 or ≥90 mm Hg, respectively, or the use of antihypertensive medications. Masticatory performance was assessed using a chewable gummy jelly. The number of teeth and denture use were visually assessed by a trained dental hygienist. Poisson regression analyses were carried out to estimate the prevalence ratio and 95% confidence interval (CI) of hypertension with the number of teeth (≥28, 20-27, or 0-19 teeth), quartiles of masticatory performance (Q1: highest [reference] to Q4: lowest), and tooth loss with/without denture use. Hypertension was significantly associated with masticatory performance in participants in Q3 (prevalence ratio = 1.35; 95% CI = 1.07, 1.72) and Q4 (prevalence ratio = 1.31; 95% CI = 1.01, 1.69). There was no association between tooth loss and hypertension. Compared to participants with >28 teeth, the prevalence ratios and 95% CIs of those without dentures and those with 20-27 teeth were 1.33 (95% CI = 1.06, 1.68) and 1.69 (95% CI = 1.21, 2.37), respectively, in those with 0-19 teeth. Masticatory performance was inversely associated with hypertension, and tooth loss without the use of dentures was related to hypertension. Therefore, masticatory function may be important for preventing hypertension among older adults.

Combined association of oral and skeletal muscle health with type 2 diabetes mellitus among community-dwelling older adults in Japan: a cross-sectional study.

Objective: Although oral health and skeletal muscle status are known to be risk factors for type 2 diabetes mellitus (T2DM), there is limited information on their combined effects among community-dwelling older adults. The purpose of this study was to investigate the association between oral health and skeletal muscle status among older adults with T2DM in Japan. Participants and Methods: This cross-sectional study included data from individuals aged ≥60 years. T2DM was defined as a glycosylated hemoglobin A1c level ≥48 mmol/mol (≥6.5%) or the use of hypoglycemic agents. For oral health status, dental hygienists assessed the number of teeth (NT) and masticatory function (MF). Skeletal muscle status was assessed using skeletal muscle mass index (SMI) and handgrip strength (HGS). Logistic regression analysis examined T2DM in nine-category combinations of oral health status (each of the three categories in NT and MF) and skeletal status (each of the three categories in SMI and HGS). Results: T2DM was prevalent in 83 participants (16.4%) and was significantly associated with low NT and SMI (odds ratio [OR] = 5.93, 95% confidence interval [CI]: 1.37-25.73) and low MF and SMI (OR = 4.48, 95% CI: 1.23-16.35) compared to high NT and SMI and high MF and SMI, respectively. Conclusion: Our findings indicate that low muscle mass with tooth loss or masticatory dysfunction is associated with T2DM among community-dwelling older adults. This suggests that maintaining oral health and muscle mass may be an effective strategy for the prevention of T2DM.

Relationship between Masticatory Function and Bone Mineral Density in Community-Dwelling Elderly: A Cross-Sectional Study.

The relationship between masticatory function and bone mineral density (BMD) is unclear. This cross-sectional study examined this relationship after adjusting for confounding factors. The subjects were 702 community-dwelling elderly adults (306 men, 396 women) who had been recruited for the Community-Based Healthcare Research and Education study in 2019. Objective masticatory function was assessed using the gummy jelly method. The median for each descriptive statistic was 69.0 years for age, 86.2% for the young adult mean, and 18.0 for masticatory function. Comparisons of the groups with good and poor masticatory function by sex revealed a significant difference in muscle mass and the tooth number for both sexes (p < 0.05). Men showed significant differences in age (p < 0.05) and salivary occult blood findings (p < 0.05). Multivariate analysis using propensity scores showed a significant association between masticatory function and BMD in both sexes (men: odds ratio 163.0, 95% confidence interval 1.36-19,610.55, p = 0.04; women: odds ratio 48.65, 95% confidence interval 1.52-1561.15, p = 0.03 in women). Masticatory function and BMD in the community-dwelling elderly may be related. However, other factors, including frailty and sarcopenia, may also be involved. Regular oral health care by dentists and dental hygienists may benefit this population.

Number of teeth and masticatory function are associated with sarcopenia and diabetes mellitus status among community-dwelling older adults: A Shimane CoHRE study.

OBJECTIVES: We aimed to examine the number of teeth and masticatory function as oral health indices and clarify their roles in the pathogenesis of sarcopenia and diabetes mellitus in community-dwelling older adults. SUBJECTS AND METHODS: This cross-sectional study was conducted with 635 older adults in Ohnan, Shimane Prefecture, in rural Japan. The number of teeth and masticatory function (measured by the number of gummy jelly pieces collected after chewing) were evaluated by dental hygienists. Sarcopenia status was assessed using handgrip strength, skeletal muscle index, calf circumference, and a possible sarcopenia diagnosis based on the Asian Working Group for Sarcopenia 2019. Diabetes mellitus status was defined as a hemoglobin A1c level ≥6.5% or self-reported diabetes. A multivariable logistic regression model was used to analyze the association between oral health, sarcopenia, and diabetes mellitus after adjusting for confounders. RESULTS: After adjusting for all confounders, logistic regression analysis showed that the number of remaining teeth was negatively associated with a low level of handgrip strength (odds ratio [OR], 0.961; 95% confidence interval [CI], 0.932-0.992) and possible sarcopenia (OR, 0.949; 95% CI, 0.907-0.992). Higher levels of masticatory function were also negatively associated with a low level of handgrip strength (OR, 0.965; 95% CI, 0.941-0.990) and possible sarcopenia (OR, 0.941; 95% CI, 0.904-0.979). Logistic regression analysis showed that the number of remaining teeth and a higher level of masticatory function were negatively associated with diabetes mellitus (OR, 0.978; 95% CI, 0.957-0.999; OR, 0.976; 95% CI, 0.960-0.992, respectively). CONCLUSION: Our findings suggest that improvement in oral health, including the maintenance of masticatory function and remaining teeth, may contribute to the prevention of sarcopenia and diabetes mellitus in older adults.

Relationship between Oral Health Status and Bone Mineral Density in Community-Dwelling Elderly Individuals: A Cross-Sectional Study.

The relationship between oral health status and bone mineral density has been poorly elucidated. We conducted a cross-sectional study to examine the relationship between oral health status and bone mineral density with data from healthy community-dwelling elderly individuals in Ohnan-cho, Shimane Japan who were recruited in 2019 for the Shimane Center for Community-Based Health Research and Education (CoHRE) study. The study included 702 participants (306 men and 396 women). The median age, bone mineral density, and number of remaining teeth were 69.0 years, 86.2%, and 26.0, respectively. The two groups (Low teeth group and High teeth group) showed significant differences in age, hemoglobin A1c (HbA1c) level, and masticatory function in men (p < 0.05). In women, age, number of untreated teeth, and masticatory function were significantly different (p < 0.05). The odds ratio of propensity score analysis for the association between the number of remaining teeth and bone mineral density was 27.7 (95% confidence interval: 1.86-414.9, p < 0.05). The number of remaining teeth could be associated with bone mineral density in the healthy elderly women, and no significant association was observed in men. Number of remaining teeth and bone mineral density may be interrelated, and oral care by dentists/dental hygienists may play an important role in maintaining bone mineral density in elderly women.

Is Accessibility to Dental Care Facilities in Rural Areas Associated with Number of Teeth in Elderly Residents?

Given that public transportation networks are less developed in rural than in urban areas, a lack of accessibility to dental care facilities could be a barrier to routine dental checkups. Thus, we hypothesized that the distance to the dental care facilities is a risk factor for tooth loss. The aim of this study was to test whether there is an association between the distance to dental care facilities, estimated by geographic information systems, and number of teeth, assessed by an oral examination, among elderly residents of a rural area in Japan. Data were collected in 2016 from a cross-sectional study conducted in Shimane prefecture, Japan. After excluding participants with missing data (n = 21), we analyzed data from 710 participants. Of them, 40.6% were male and the mean (standard deviation) age was 67.4 (7.4) years. Further, 68.0% (n = 483) had at least 20 teeth. We found that the distance to dental care facilities was significantly associated with the number of teeth (less than 20) (odds ratio = 1.07, 95% confidence interval = 1.01-1.12) after adjustment for potential confounders. This result suggested that individuals without easy access to dental care facilities may be important targets for dental care.

Accessible Transportation, Geographic Elevation, and Masticatory Ability Among Elderly Residents of a Rural Area.

Given that public transportation networks are often worse in rural areas than in urban areas, rural residents who do not drive can find it difficult to access health-promoting goods, services, and resources related to masticatory ability. Moreover, geographical location, assessed by elevation, could modify this association. The aim of this study was to test whether the association between access to transportation and masticatory ability varied by elevation. Data were collected from a cross-sectional study conducted in Mizuho and Iwami counties, Japan. Objective masticatory ability was evaluated using a test gummy jelly and elevation was estimated by the geographic information systems according to the participant's address. After excluding subjects with missing data, 672 subjects (Mizuho = 401 and Iwami = 271) were analyzed. After adjustment for potential confounders, being a driver was not significantly associated with masticatory ability among elderly people living at low elevation (≤313 m) in Mizuho county. However, after the same adjustment, being a driver remained significantly associated with increased masticatory ability among elderly at high elevations. Similar findings were observed in Iwami county. Accessible transportation was significantly associated with increased mastication ability in elderly people living at high elevations, but not in those living at low elevations.