Misuzu Sato

Hyposalivation and dietary nutrient intake among community‐based older Japanese

Saliva is important for maintaining oral function and regulating oral health. Reduced saliva flow rate, which is common among older adults, has been reported to be associated with perceived chewing and swallowing difficulties; however, its relationship to actual nutrient intake is unclear. The aim of the present cross‐sectional study was to evaluate the relationship between hyposalivation and nutrient intake among older Japanese adults.

Longitudinal relationship between metabolic syndrome and periodontal disease among Japanese adults aged ≥70 years: the Niigata Study.

BACKGROUND There has been little evaluation in longitudinal epidemiologic studies of the effect of metabolic syndrome (MetS) on periodontal status. The specific aim of this longitudinal study is to investigate whether MetS in the Japanese population could be a risk factor for periodontal disease. METHODS A total of 125 older adults from Japan for whom data were available for the years 2003 to 2006 were selected for the current study. Full-mouth periodontal status, measured as clinical attachment level (CAL), was recorded at baseline and in follow-up examinations. Development of periodontal disease was considered to be ≥2 teeth demonstrating a longitudinal loss of proximal attachment of ≥3 mm at the follow-up dental examination. A multivariable Poisson regression model with robust error variance was used to evaluate the association of MetS defined by the modified National Cholesterol Education Program Adult Treatment Panel III criteria with development of periodontal disease. Adjustments for sex, income, education, smoking status, number of teeth at baseline, mean CAL at baseline, pattern of visits to a dentist, and brushing frequency were considered. RESULTS The prevalence of MetS was 21.6% (27/125). Study participants with MetS were approximately 2.6 times more likely to develop periodontal disease (adjusted relative risk 2.58, 95% confidence interval 1.17 to 5.67) after simultaneous adjustment for other covariates. CONCLUSIONS These findings support the hypothesis that MetS may be a risk factor for periodontal disease in older Japanese individuals. Additional studies with larger, more diverse populations and more complete information are needed to substantiate the findings.

Serum antibody to Porphyromonas gingivalis in metabolic syndrome among an older Japanese population.

BACKGROUND AND OBJECTIVE Potentially significant associations between metabolic syndrome (MetS) and periodontal disease have been reported in recent studies; however, there is a dearth of literature regarding the relationship of MetS with serum antibody levels to periodontal pathogens. The aim of this cross-sectional study was to investigate the association between MetS and serum antibody to the periodontal pathogen Porphyromonas gingivalis (P. gingivalis) in 216 Japanese individuals aged 79 years. MATERIALS AND METHODS Serum antibody levels to P. gingivalis were measured by enzyme-linked immunosorbent assay. An elevated serum antibody response was defined as the upper quartile and was considered as the outcome variable. A multivariable logistic regression model was used to evaluate the association of MetS defined by the modified National Cholesterol Education Program Adult Treatment Panel III criteria with an elevated antibody status. Adjustments for gender, income, education, smoking status, dental-care utilisation patterns and brushing frequency were considered. RESULTS The prevalence of MetS was 22.2% (n = 48). Study participants with MetS were 2.9 times more likely to have an elevated serum antibody to P. gingivalis (adjusted odds ratio = 2.91, 95% confidence interval = 1.24-6.85) after simultaneous adjustment for other covariates. CONCLUSION Our findings suggest an independent relationship between MetS and serum antibody levels to P. gingivalis in the Japanese elderly. Additional longitudinal epidemiologic studies with larger, more diversified samples and more complete information are needed to substantiate our findings.

Effect of periodontal treatment on adipokines in type 2 diabetes

The association between adipokines and inflammatory periodontal diseases has been studied over the last two decades. This review was intended to explore the observation that periodontal therapy may lead to an improvement of adipokines in diabetic patients. In summary, substantial evidence suggests that diabetes is associated with increased prevalence, extent and severity of periodontitis. Numerous mechanisms have been elucidated to explain the impact of diabetes on the periodontium. However, current knowledge concerning the role of major adipokines indicates only some of their associations with the pathogenesis of periodontitis in type 2 diabetes. Conversely, treatment of periodontal disease and reduction of oral inflammation may have positive effects on the diabetic condition, although evidence for this remains somewhat equivocal.

Longitudinal association of dentition status with dietary intake in Japanese adults aged 75 to 80 years

Limited information is available on the temporal association between dentition status and dietary intake. The aim of this 5-year prospective cohort study was to investigate whether impaired dentition was associated with subsequent decline in dietary intake in older Japanese adults. Two hundred and eighty-six community-dwelling Japanese individuals, all aged 75 years at baseline, were included in the study. Functional tooth units (FTUs), defined as a pair of opposing natural or prosthetic teeth excluding third molars (range: 0-14), were counted on the basis of baseline dental examinations. Individuals with ≤5 FTUs were defined as having impaired dentition. Dietary intake was assessed at baseline and 5 years later, using a validated dietary questionnaire. Robust regression analyses were used to evaluate the differences in change in dietary intake between participants with and without impaired functional dentition, after adjustment for potential confounders. Sixty-one study participants (21·3 %) were defined as having impaired dentition. Overall, mean values for all estimated dietary variables (energy, nutrients and food groups) declined over time. Notably, individuals with impaired dentition demonstrated a significantly (P < 0·05) greater degree of decline in the intake of multiple nutrients (protein, sodium, potassium, calcium, vitamin A, vitamin E and dietary fibre) and food groups (vegetable and meat) than those without impaired dentition, after adjusting for potential confounders. The results of this study describe the temporal association of impaired dentition with the decline in selected nutrient and food group intake among older Japanese adults.

Association between tooth loss and medical costs related to stroke in healthy older adults aged over 75 years in Japan

Growing evidence suggests that tooth loss is associated with increased risk of stroke. In the current study, we investigated cumulative medical costs related to stroke using data from the Advanced Elderly Medical Service System. We hypothesized that tooth loss was associated with an increase in medical costs related to stroke among older Japanese adults.

Maximum bite force at age 70 years predicts all-cause mortality during the following 13 years in Japanese men

There is limited information on the impact of oral function on mortality among older adults. The aim of this prospective cohort study was to examine whether an objective measure of oral function, maximum bite force (MBF), is associated with mortality in older adults during a 13-year follow-up period. Five hundred and fifty-nine community-dwelling Japanese (282 men and 277 women) aged 70 years at baseline were included in the study. Medical and dental examinations and a questionnaire survey were conducted at baseline. Maximum bite force was measured using an electronic recording device (Occlusal Force-Meter GM10). Follow-up investigation to ascertain vital status was conducted 13 years after baseline examinations. Survival rates among MBF tertiles were compared using Cox proportional hazards regression models stratified by sex. There were a total of 111 deaths (82 events for men and 29 for women). Univariable analysis revealed that male participants in the lower MBF tertile had increased risk of all-cause mortality [hazard ratio (HR) = 1·94, 95% confidence interval (CI) = 1·13-3·34] compared with those in the upper MBF tertile. This association remained significant after adjustment for confounders (adjusted HR = 1·84, 95% CI = 1·07-3·19). Conversely, no association between MBF and all-cause mortality was observed in female participants. Maximum bite force was independently associated with all-cause mortality in older Japanese male adults. These data provide additional evidence for the association between oral function and geriatric health.

Association between periodontitis and medical expenditure in older adults: A 33-month follow-up study.

Along with rapid aging, medical expenditure for older adults has been increasing in Japan. Research has shown that periodontitis is a useful predictor for excess medical expenditure; however, limited information is available on the elderly population after adequately considering confounding factors. The aim of the present study was to evaluate the association between periodontitis and long‐term medical expenditure in elderly Japanese.

Effects of Periodontal Diseases on Diabetes-Related Medical Expenditure

We conducted a review of English papers published between 2012 and April 2015 for associations between periodontal disease and diabetes-related medical expenditure. This resulted in only one paper being selected, which demonstrated that, to date, very little information exists on this topic. Although the evidence is limited, the current research findings support the hypothesis that periodontal disease is an important predictor for the growth of medical spending related to diabetes among the US population. Our ongoing project based on a Japanese elderly population also produced concordant results. It is necessary to conduct further research to accumulate more evidence and to be able to generalize these findings. Because periodontal disease is largely modifiable, controlled intervention studies are needed to elucidate whether health-care spending related to diabetes could be reduced thorough adequate preventive dental care, proper dental education, and oral health promotion.

Dentition status and frailty in community‐dwelling older adults: A 5‐year prospective cohort study

To examine the longitudinal association between dentition status and incidence of frailty in older adults.