Masumi Muramatsu

Relationships between perceived chewing ability and muscle strength of the body among the elderly

The aim of the present study was to elucidate whether self-assessed masticatory ability (masticatory ability) is significantly related to muscle strength of the body evaluated as handgrip strength and skeletal muscle mass of the whole body (kg) (SMM) after adjusting for confounding variables, including, age, gender, height, weight, employment status, type of household, educational background, social interaction, chronic medical conditions, smoking habit, drinking habits and dentition status among the elderly. A total of 381 persons aged 67-74 years were enrolled. Masticatory ability was classified into one of three categories: ability to chew all kinds of food, ability to chew only slightly hard food or ability to chew only soft or pureed food. Handgrip strength was measured, and bioimpedance analysis was used to estimate SMM. One-way analysis of variance and Bonferroni methods were used to examine differences in handgrip strength and SMM among the three groups of masticatory ability. An ordinal regression model was conducted with masticatory ability as the dependent variable and handgrip strength as the principal independent variable. Handgrip strength was significantly lower in those individuals who could chew only soft or pureed food than in those individuals who could chew all kinds of food. No significant difference in SMM was found among the three groups of masticatory ability. Masticatory ability was significantly related to handgrip strength after adjusting for SMM, dentition status and background factors. Chewing ability may be related to muscle strength of the body evaluated as handgrip strength, but not evaluated as SMM.

Associations between self-assessed masticatory ability and higher brain function among the elderly.

Among the elderly, the quality of higher brain function is a contributing factor in performing activities of daily living. The aim of the study is to elucidate, epidemiologically, associations between mastication and higher brain function. A total of 208 community-dwelling elderly persons, aged 70-74 years, were enrolled. Self-assessed masticatory ability (masticatory ability) was classified into one of three categories: ability to chew all kinds of food, ability to chew only slightly hard food, or ability to chew only soft or pureed food. Brain function was assessed by four neuropsychological tests: Ravens Colored Progressive Matrices (RCPM) test, the Verbal Paired Associates 1 (VerPA) task and the Visual Paired Associates 1 task (from the Wechsler Memory Scale Revised Edition), and the Block Design subtest (from the Wechsler Adult Intelligence Scales-Third Edition). Correlations between masticatory ability and each test were examined using Spearman rank correlation coefficients. Multinominal logistic regression models were conducted with the neuropsychological tests as the dependent variables and masticatory ability as the principal independent variable to adjust for age, gender, educational background, social activity, drinking/smoking habits, chronic medical conditions and dental status. Significant correlations were found between the RCPM test, the VerPA task, the Block Design test and masticatory ability. In multinominal logistic regression models, poor masticatory ability was significantly and independently related to the categories under the mean-s.d. points compared with those of the mean ± s.d. ranges for RCPM test and the VerPA task. Significant associations may exist between mastication and higher brain function among the elderly.

Self-assessed masticatory ability and hospitalisation costs among the elderly living independently.

The escalating medical costs are a social problem in many countries. Masticatory ability is thought to be related to the general health conditions. The purpose of this study was to show relationships between self-assessed masticatory ability and medical costs among the elderly living independently in community. Data on background factors and self-assessed masticatory ability were collected from 702 Japanese elderly persons by questionnaires. An intra-oral examination was performed to examine the number of remaining teeth. Self-assessed masticatory ability was classified into one of three categories: ability to chew all kinds of food (Good), ability to chew only slightly hard food (Fair) or ability to chew only soft or pureed food (Poor). Data on the annual medical excluding dental costs were obtained from the Japanese National Health Insurance system. The Kruskal-Wallis test was used to examine differences in outpatient costs and hospitalisation costs among the three groups of self-assessed masticatory ability. Univariate unconditional logistic regression models and multivariate logistic regression models were used with medical costs as the dependent variable and self-assessed masticatory ability as the principal independent variable. A significant difference (P=0·039) in hospitalisation costs but not outpatient costs was found among the three groups of self-assessed masticatory ability. The multivariate logistic regression analysis showed that severely impaired masticatory ability (Poor) was significantly related to higher costs of hospitalisation. Self-assessed impairment of masticatory ability may be a significant and independent indicator of higher costs of hospitalisation among community-dwelling elderly persons.

SELF-ASSESSED IMPAIRMENT OF MASTICATORY ABILITY AND LOWER SERUM ALBUMIN LEVELS AMONG COMMUNITY-DWELLING ELDERLY PERSONS

SUMMARY Background: Serum albumin is considered a key nutrient that is significantly related to general health among elderly persons. The aim of the present study was to determine the relationship between masticatory ability and serum albumin levels in the elderly. Methods: A total of 768 persons were enrolled in the study. Data on background factors and the self-assessed masticatory ability were collected by means of questionnaires. An intraoral examination was performed to examine the pattern of occluding pairs of natural teeth, and blood samples were collected from the cutaneous vein to measure serum albumin levels. A forward stepwise multivariate logistic model was constructed with serum albumin levels as the dependent variable and the self-assessed masticatory ability as the principal independent variable, to adjust for potential confounding variables. Results: Sex, current employment status, social interaction, and self-assessed masticatory ability were retained in the final model, and they were significantly associated with serum albumin levels. The odds ratios for lower levels of serum albumin (≤ 40 g/L) were 1.88 for males, 1.70 for non-working status, 1.55 for low social activity status, and 1.43 for the self-assessed impairment of masticatory ability. Conclusion: A weak, statistically significant relationship may exist between self-assessed impairment of masticatory ability and lower levels of serum albumin in the elderly living independently. [International Journal of Gerontology 2010; 4(2): 89–95]

Relationship between subjective assessment of oral health and medical expenses in community-dwelling elderly persons

Objectives The increasing medical expenses of elderly persons in Japan’s rapidly ageing society have become a major concern. It is therefore important to elucidate the factors associated with such escalation. Here, we focused on the relationship between subjective self-assessment of oral health, as an index of general health, and medical expenses (excluding dental repair) under the hypothesis that oral health contributes to general medical expenses. Several studies have shown that oral health status is correlated with general health status among elderly persons. We speculated that oral health status might show a relation with medical costs among elderly persons. However, few studies have investigated this relationship to date. Materials and Methods Participants were 259 elderly subjects (range: 65–84 years; 120 men, 139 women) residing independently. Subjective assessment of oral health was evaluated by their responses (‘Good’, ‘Not good’ and ‘Not at all good’) on a survey questionnaire. The correlation between subjective assessment of oral health and medical expenditure was analysed using Spearman’s rank method, the Mann–Whitney U-test and the Kruskal–Wallis test. Medical expenses were used as the dependent variable in multinomial logistic regression analysis with background and intraoral factors as independent variables. Results A slight yet statistically significant correlation was observed between subjective assessment of oral health and outpatient treatment fees. Conclusion The findings revealed that subjective assessment of oral health is significantly and independently related to the medical expenses of community-dwelling elderly persons after adjusting for social background, living environment and physical factors.

Relationships between Geriatric Oral Health Assessment Index scores and general physical status in community‐dwelling older adults

OBJECTIVE The aim of this study was to investigate the relationships between Geriatric Oral Health Assessment Index (GOHAI) and general physical status among community-dwelling older adults. BACKGROUND Geriatric Oral Health Assessment Index is a patient-centred assessment of oral health for older adults. We hypothesised that GOHAI is a significant indicator of general physical status of older adults. METHODS This study included 354 adults (age, ≥65 years) living independently. Body mass index, handgrip strength and one-leg standing time with eyes open were used to evaluate the general physical status. Spearmans rank correlation coefficients were calculated to examine the relationships between the GOHAI scores, its three subdivided categories (physical function, psychological function and pain and discomfort) and each physical status measurement. A stepwise linear regression model was applied with each physical status measurement as the dependent variable and the GOHAI scores and its subdivisions as the principal independent variable. RESULTS Positive correlations were found between the GOHAI scores, its three subdivided categories and handgrip strength. The physical function category positively correlated with one-leg standing time. The GOHAI and the pain and discomfort category scores were retained in the final models of stepwise regression for handgrip strength, and significant relationships persisted after adjustments for demographic, psychosocial, medical and dental status. CONCLUSION The GOHAI scores and its pain and discomfort category score may be significant indicators of body muscle strength.