Posterior Teeth Occlusion Associated with Cognitive Function in Nursing Home Older Residents: A Cross-Sectional Observational Study

Early detection and subsequent reduction of modifiable risk factors for cognitive decline is important for extending healthy life expectancy in the currently aging society. Although a recent increase in studies on the state or number of the teeth and cognitive function, few studies have focused on the association between posterior teeth occlusion necessary to maintain chewing function and cognitive function among older adults. This study examined the association between posterior teeth occlusion and cognitive function in nursing home older residents. In this cross-sectional study, 279 residents aged ≥60 years from eight nursing homes in Aso City, Japan participated in cognitive function and dental status assessments and completed a comprehensive questionnaire survey in 2014. Cognitive function was measured using a Mini-Mental State Examination (MMSE). Posterior teeth occlusion was assessed using a total number of functional tooth units (total-FTUs), depending on the number and location of the remaining natural and artificial teeth on implant-supported, fixed, and removable prostheses. Linear regression models were used to assess univariate and multivariate associations between total-FTUs and MMSE scores. Models were sequentially adjusted for demographic characteristics, number of natural teeth, socioeconomic status, health behaviors, comorbidities, physical function, and nutritional status. Among the 200 residents included in our analysis, mean MMSE scores and total-FTUs were 11.0 ± 8.6 and 9.3 ± 4.6, respectively. Higher total-FTUs were significantly associated with higher MMSE scores after adjustment for demographics and teeth number (B = 0.48, 95% confidence interval [CI] = 0.22–0.74). The association remained significant even after adjustment for all covariates (B = 0.25, 95% CI = 0.01–0.49). The current findings demonstrated that loss of posterior teeth occlusion was independently associated with cognitive decline in nursing home older residents in Japan. Maintenance and restoration of posterior teeth occlusion may be a preventive factor against cognitive decline in aged populations.

Prognosis of uveal melanoma based on race in 8100 patients: The 2015 Doyne Lecture

A retrospective, nonrandomized, interventional case series of 8100 patients with uveal melanoma were evaluated for melanoma-related metastasis based on patient race. The patient race was Caucasian (n=7918, 98%), Hispanic (n=105, 1%), Asian (n=44, <1%), or African American (n=33, <1%). On the basis of race (Caucasian, Hispanic, Asian, and African American), significant differences were noted in mean age at presentation (58, 48, 44, and 52 years; P<0.001), distance of posterior tumor margin to foveola (5, 5, 6, and 4 mm; P<0.001), distance of posterior tumor margin to optic disc (5, 5, 6, and 4 mm) (P<0.001), tumor base (11, 12, 12, and 13 mm; P<0.001), tumor thickness (5.4, 7.1, 6.5, and 7.5 mm; P<0.001), intraocular hemorrhage (10, 14, 11, and 24%; P=0.02), and rupture of Bruch's membrane (20, 27, 39, and 36%; P=0.001). On the basis of multivariate analysis, the rate of metastasis increased with increasing age (P<0.001), ciliary body location (P<0.001), increasing tumor base (P<0.001), increasing tumor thickness (P<0.001), pigmented tumor (P=0.001), subretinal fluid (P=0.001), intraocular hemorrhage (P=0.045), and extraocular extension (P=0.036). Kaplan-Meier estimates of metastasis at 3, 5, and 10 were 8, 15, and 25% in Caucasians; 13, 13, and 13% in Hispanics; 4, 4, and 36% in Asians; and 8, 8, and 8% in African Americans. Compared with Caucasians, despite relative risk for metastasis of 0.31 for African Americans, 0.73 for Hispanics, and 1.42 for Asians, there was no statistical difference in metastasis, or death from uveal melanoma based on race. In summary, uveal melanoma showed similar prognosis for all races.

Cancer whole-genome sequencing: present and future

Recent explosive advances in next-generation sequencing technology and computational approaches to massive data enable us to analyze a number of cancer genome profiles by whole-genome sequencing (WGS). To explore cancer genomic alterations and their diversity comprehensively, global and local cancer genome-sequencing projects, including ICGC and TCGA, have been analyzing many types of cancer genomes mainly by exome sequencing. However, there is limited information on somatic mutations in non-coding regions including untranslated regions, introns, regulatory elements and non-coding RNAs, and rearrangements, sometimes producing fusion genes, and pathogen detection in cancer genomes remain widely unexplored. WGS approaches can detect these unexplored mutations, as well as coding mutations and somatic copy number alterations, and help us to better understand the whole landscape of cancer genomes and elucidate functions of these unexplored genomic regions. Analysis of cancer genomes using the present WGS platforms is still primitive and there are substantial improvements to be made in sequencing technologies, informatics and computer resources. Taking account of the extreme diversity of cancer genomes and phenotype, it is also required to analyze much more WGS data and integrate these with multi-omics data, functional data and clinical-pathological data in a large number of sample sets to interpret them more fully and efficiently.

Risk factors for reduced salivary flow rate in a Japanese population: the Hisayama Study

The purpose of this study was to determine distinct risk factors causing reduced salivary flow rate in a community-dwelling population using a prospective cohort study design. This was a 5-year follow-up survey of 1,377 community-dwelling Japanese individuals aged ≥40 years. The salivary flow rate was evaluated at baseline and follow-up by collecting stimulated saliva. Data on demographic characteristics, use of medication, and general and oral health status were obtained at baseline. The relationship between reduced salivary flow rate during the follow-up period and its predictors was evaluated after adjustment for confounding factors. In a multivariate logistic regression model, higher age and plaque score and lower serum albumin levels were significantly associated with greater odds of an obvious reduction in salivary flow rate (age per decade, odds ratio [OR] = 1.25, 95% confidence interval [CI] = 1.03-1.51; serum albumin levels <4 g/dL, OR = 1.60, 95% CI = 1.04-2.46; plaque score ≥1, OR = 1.53, 95% CI = 1.04-2.24). In a multivariate linear regression model, age and plaque score remained independently associated with the increased rate of reduced salivary flow. These results suggest that aging and plaque score are important predictors of reduced salivary flow rate in Japanese adults.

Dental plaque development on a hydroxyapatite disk in young adults observed by using a barcoded pyrosequencing approach

Dental plaque is a dynamic microbial biofilm ecosystem that comprises hundreds of species including difficult-to-cultivate bacteria. We observed the assembly of a plaque bacterial community through 16S rRNA gene analysis. Plaque samples that accumulated on a hydroxyapatite disk for 1, 2, 3, 4, 5, and 7 days with saliva on day 0 were collected from 19 young adults using a removable resin splint. Quantitative PCR analysis showed that the total bacterial amount gradually increased and reached a plateau on day 4. Barcoded pyrosequencing analysis revealed that the microbial richness and diversity particularly increased between days 5 and 7. A principal coordinate analysis plot based on unweighted UniFrac showed the community assembly in a time-related manner, which became increasingly similar to the salivary microbiota. Facultative anaerobic bacteria such as Streptococcus, Neisseria, Abiotrophia, Gemella, and Rothia were predominant in the plaque bacterial community in the earlier days, whereas obligate anaerobes, such as Porphyromonas, Fusobacterium, Prevotella, and Capnocytophaga showed increased dominance on later days. UniFrac analysis also demonstrated that dental caries experience had a significant effect on the assembly process. Our results reveal the development pattern of the plaque bacterial community as well as the inter-individual differences associated with dental caries experience.

Distinct composition of the oral indigenous microbiota in South Korean and Japanese adults

A comparison of national surveys on oral health suggested that the population of South Korea has a better periodontal health status than that of Japan, despite their similar inherent backgrounds. Here, we investigated differences in oral bacterial assemblages between individuals from those two countries. To exclude potential effects of oral health condition on the microbiota, we selected 52 Korean and 88 Japanese orally healthy adults (aged 40-79 years) from the participants of two cohort studies, the Yangpyeong study in South Korea and the Hisayama study in Japan, and compared the salivary microbiomes. The microbiota of the Japanese individuals comprised a more diverse community, with greater proportions of 17 bacterial genera, including Veillonella, Prevotella, and Fusobacterium, compared to the microbiota of the Korean individuals. Conversely, Neisseria and Haemophilus species were present in much lower proportions in the microbiota of the Japanese individuals than the Korean individuals. Because higher proportions of Prevotella and Veillonella and lower proportions of Neisseria and Haemophilus in the salivary microbiome were implicated in periodontitis, the results of this study suggest that the greater proportion of dysbiotic oral microbiota in the Japanese individuals is associated with their higher susceptibility to periodontitis compared to the Korean individuals.

Relationship between increases in BMI and changes in periodontal status: a prospective cohort study

AIM

The purpose of this prospective cohort study was to investigate whether body mass index (BMI) and oral health behaviour are related to changes in periodontal status in Japanese university students.

MATERIALS AND METHODS

Students (n = 224) who were interested in receiving oral health examinations before entering university and before graduation were included in the analysis. Subjects were investigated regarding the correlations of oral health behaviours and increases in BMI with the percentage of bleeding on probing (%BOP) and Community Periodontal Index (CPI) scores as indicators of changes in periodontal status.

RESULTS

The risk of increased %BOP was associated with the non-use of dental floss (adjusted odds ratio [OR]: 3.11; 95% confidence interval [CI]: 1.31-7.37; p < 0.05), whereas the risk of increased CPI score was associated with increases in BMI (OR: 1.95; 95% CI: 1.05-3.65; p < 0.05) and simplified oral hygiene index score (OR: 2.28; 95% CI: 1.23-4.22; p < 0.01).

CONCLUSION

Increases in BMI were associated with worsening of periodontal status, defined as increased CPI score in Japanese university students, whereas lack of inter-dental cleaning was associated with exacerbated gingival bleeding.

Nutritional status and dysphagia risk among community-dwelling frail older adults

OBJECTIVES

Although the presence of dysphagia is a key determinant of nutritional status among older adults, few studies have focused on the association between malnutrition and dysphagia risk in community-dwelling frail older adults. This study estimated the prevalence of malnutrition and quantified the association between malnutrition and dysphagia risk among community-dwelling older Japanese adults requiring long-term care.

DESIGN

Cross-sectional study.

SETTING

This study was conducted with the cooperation of the Japan Dental Association and local dental associations in all 47 prefectures from January to February 2012.

PARTICIPANTS

Individuals aged ≥65 years capable of oral nutrient intake who were living at home and receiving home dental care and treatment.

MEASUREMENTS

Individual demographic characteristics and factors associated with health loss-related functional decline were obtained through interviews by home-visit dentists and self-administered questionnaires. Nutritional status and dysphagia risk were evaluated using the Mini Nutritional Assessment Short Form and the Dysphagia Risk Assessment for the Community-dwelling Elderly.

RESULTS

Among 874 respondents (345 men and 529 women), 24.6% were malnourished, 67.4% were at risk of malnutrition, and 8.0% were well nourished. Dysphagia risk was related to an increased likelihood of malnutrition at an old age, even after adjusting for covariates (PR = 1.30, 95% CI = 1.01-1.67).

CONCLUSION

Malnutrition is highly prevalent among community-dwelling frail older adults, and dysphagia risk is independently associated with malnutrition. Dysphagia may be an important predictor of malnutrition progression in aged populations.

Gender differences in the association between metabolic syndrome and periodontal disease: the Hisayama Study

Aims: Periodontal disease and metabolic syndrome (MS) are more prevalent in males than in females. However, whether there is a gender difference in the association between these health conditions has not yet been investigated. This study examined the gender difference in this association, considering the definition of periodontal disease.

Materials and Methods: We recruited 1040 males and 1330 females, aged ≥40 years, with at least ten teeth from subjects of the 2007 Hisayama health examination. We performed a logistic regression analysis with various definitions of periodontal disease the dependent variable and MS as the independent variable. Following the analysis, the data were reanalysed with the structural equations model.

Results: The logistic regression analysis suggested a stronger association between periodontal disease and MS in females than that in males when periodontal disease was more severely defined. When we constructed the structural equations model in each gender, the model showed a good fit to the data of females, suggesting the association between periodontal disease and MS in females, but not in males.

Conclusions: Gender differences seem to exist in the association between periodontal disease and MS; MS might show a stronger association with periodontal disease in females than in males.

Furuta M, Shimazaki Y, Takeshita T, Shibata Y, Akifusa S, Eshima N, Kiyohara Y, Ninomiya T, Hirakawa Y, Mukai N, Nagata M, Yamashita Y. Gender differences in the association between metabolic syndrome and periodontal disease: the Hisayama Study. J Clin Periodontol 2013; 40: 743–752. doi: 10.1111/jcpe.12119.

Relationships between self-rated oral health, subjective symptoms, oral health behavior and clinical conditions in Japanese university students: a cross-sectional survey at Okayama University

Background

Self-rated oral health is a valid and useful summary indicator of overall oral health status and quality of life. However, few studies on perception of oral health have been conducted among Japanese young adults. This study investigated whether oral health behavior, subjective oral symptoms, or clinical oral status were associated with self-rated oral health in Japanese young adults.

Methods

This cross-sectional survey included 2,087 students (1,183 males, 904 females), aged 18 and 19 years, at Okayama University, Japan. A self-administered questionnaire was distributed and an oral examination was performed.

Results

In a structural equation modeling analysis, the score of decayed, missing and filled teeth (DMFT) significantly affected self-rated oral health (p <0.05) and the effect size was highest. Malocclusion, subjective symptoms of temporomandibular disorders (TMD) and stomatitis, and poor oral health behavior significantly induced self-rated poor oral health with small effect sizes (p <0.05). Clinical periodontal conditions and Oral Hygiene Index-simplified were not related to self-rated oral health.

Conclusion

Self-rated oral health was influenced by subjective symptoms of TMD and stomatitis, oral health behavior, the score of DMFT, and malocclusion. The evaluation of these parameters may be a useful approach in routine dental examination to improve self-rated oral health in university students.

Oral Health and Swallowing Problems

Oral health impacts systemic health. Therefore, oral care is an important consideration in maintaining quality of life (QOL). Previously, maintenance and improvement of oral hygiene was considered essential for achieving oral health. In addition to oral hygiene, oral care in terms of oral function is now considered to maintain QOL. Ingestion of exogenous nutrients via the oral cavity is fundamental to the function of all higher animals, not only human beings. Chewing and swallowing processes are critical for normal food intake, and adequate saliva supply and oral care to allow proper functioning of these processes are indispensable for maintaining QOL. In this review, we will summarize the relationship between chewing and swallowing and effects of saliva secretion on these functions, and discuss methods to maintain ingestion of exogenous nutrients and prevent swallowing problems, especially in elderly people.

Dental caries is correlated with knowledge of comprehensive food education in Japanese university students

In Japan, the "Food Education Basic Law" (The Basic Law on Shokuiku, food education) was enacted in 2005. The comprehensive food education programs, namely Shokuiku, aim to improve dietary practices to reduce lifestyle-related diseases. Dental caries is one of the diseases associated with inappropriate dietary habits. Thus, food education may influence the prevalence of dental caries. However, there are no data regarding the association between public based-food education and dental caries. The aim of the present study was to investigate the relationship between knowledge about comprehensive food education (Shokuiku) and dental caries experience in Japanese university students. A total of 2,184 students (1,240 men, 944 women), aged 18-20 years, were examined. They had attended the Shokuiku program while in junior/senior high school. The numbers of teeth present, and decayed, missing and filled teeth (DMFT) (dental caries experience) were recorded. Additional information was collected via a questionnaire regarding knowledge about food education, dietary habits and oral health behavior. Of the students, 315 men (20.7%) and 345 women (52.8%) reported that they know and can explain the meaning and content of the word "Shokuiku". After adjusting for potential confounding factors, subjects who did not have knowledge about Shokuiku had higher adjusted odds ratio (OR) for dental caries experience (DMFT >0) than those who had (adjusted OR, 1.23; 95% CI, 1.02-1.48; p<0.05). These observations revealed that having knowledge about comprehensive food education in university students correlates with low prevalence of dental caries.

Effects of eating behaviors on being overweight in japanese university students: a cross-sectional survey at the Okayama University

Being overweight is an important risk factor for lifestyle-related diseases. The objective of the present study was to examine whether eating until full, eating quickly, or both eating behaviors were associated with being overweight, defined as a body mass index (BMI) ≥ 25, in young adults. This cross-sectional survey comprised 1918 students (1139 male and 779 female students) at the Okayama University in Japan. In logistic regression analysis, eating until full was not associated with being overweight in either sex. The adjusted odds ratio of being overweight among those who reported eating quickly was 3.93 (2.45-6.31; P < .0001) for male and 1.59 (0.79-3.21; P = .193) for female students. Moreover, the adjusted odds ratio of being overweight was 2.72 (1.72-4.30; P < .001) in male students who frequently reported eating a fatty diet. The combination of eating quickly and frequently eating a fatty diet had a supra-additive effect on being overweight in the male students.

Effect of exposure to non-esterified fatty acid on progressive deterioration of insulin secretion in patients with Type 2 diabetes: a long-term follow-up study

AIM

The aim of the study was to determine whether fasting serum non-esterified fatty acid (NEFA) could be associated with long-term progressive deterioration of insulin secretion in patients with Type 2 diabetes.

METHODS

Seventy-seven Japanese patients with Type 2 diabetes (mean BMI 23.3 kg/m(2) ) were followed for 10 years. We measured fasting C-peptide level every 1-2 years. By using the slope of regression line between fasting C-peptide level and duration, we calculated its individual annual decline as an index of insulin secretion. During the follow-up periods of C-peptide, the patients were evaluated for fasting serum non-esterified fatty acid, LDL cholesterol, HDL cholesterol and HbA(1c) levels for the last 8 years. We excluded patients who had renal dysfunction or anti-insulin antibodies from among the insulin-treated patients. Association between the individual annual decline of fasting C-peptide level and related factors were evaluated.

RESULTS

The mean individual annual decline of fasting serum C-peptide level was -0.013 ± 0.027 nmol/l/year. Fasting serum non-esterified fatty acid level had no significant difference between the first and the last 2 years of the 8-year observation period of non-esterified fatty acid. Using multiple regression analysis, mean fasting serum non-esterified fatty acid level was associated with the individual annual decline of fasting serum C-peptide level (standardized regression coefficient -0.358, P=0.0056), although other related factors, including HbA(1c) level, were not associated.

CONCLUSIONS

Mean fasting serum non-esterified fatty acid level during an 8-year observation was independently associated with long-term progressive deterioration of insulin secretion in Japanese patients with Type 2 diabetes.

Effects of self-efficacy on oral health behaviours and gingival health in university students aged 18- or 19-years-old

AIM

Although self-efficacy is known to affect various health-related practises, few studies have clearly examined how self-efficacy correlates with oral health behaviors or the oral health condition. We examined the relationship between gingivitis, oral health behaviors and self-efficacy in university students.

MATERIAL & METHODS

A total of 2,111 students (1,197 males, 914 females) aged 18 and 19 years were examined. The degree of gingivitis was expressed as the percentage of bleeding on probing (%BOP). Additional information was collected via a questionnaire regarding oral health behaviors (daily frequency of tooth-brushing, use of dental floss and regular check-up). Self-efficacy was assessed using the Self-Efficacy Scale for Self-care (SESS). Path analysis was used to test pathways from self-efficacy to oral health behaviors and %BOP.

RESULTS

In the final structural model, self-efficacies were related to each other, and they affected oral health behaviors. Good oral health behaviors reduced dental plaque and calculus, and lower levels of dental plaque and calculus resulted in lower %BOP.

CONCLUSION

Higher self-efficacy correlated with better oral health behaviours and gingival health in university students. Improving self-efficacy may be beneficial for maintaining good gingival health in university students. To prevent gingivitis, the approach of enhancing self-efficacy in university students would be useful.