Oral-to-rectum microbial transmission in orthopedic patients without a history of intestinal disorders

The enrichment of oral taxa in the gut has recently been reported as a notable alteration in the microbial balance in patients with intestinal disorders. However, translocation in populations without such diseases remains controversial. In this study, we examined 49 pairs of tongue and rectal samples collected from orthopedic patients without a history of intestinal disorders to verify the presence of oral taxa in the rectal microbiota. The bacterial composition of each sample was determined using 16S rRNA gene sequencing and amplicon sequence variant (ASV) analysis. Although the bacterial compositions of the tongue and rectal microbiota were distinctly different, tongue ASVs were detected in 67.3% of the participants and accounted for 0.0%-9.37% of the rectal microbiota. Particularly, Streptococcus salivarius, Fusobacterium nucleatum, and Streptococcus parasanguinis were abundant in the rectal microbiota. According to the network analysis, tongue taxa, such as S. salivarius and S. parasanguinis, formed a cohabiting group with Klebsiella pneumoniae and Alistipes finegoldii in the rectal microbiota. The total abundance of tongue ASVs in the rectal microbiota was significantly higher in participants with older age, hypertension, and proton pump inhibitor (PPI) use. Our study presents an extensive translocation of oral taxa to the rectum of a population without intestinal disorders and suggests that aging, hypertension, and PPI use are associated with an increased abundance of oral taxa and potential pathogenic bacteria in the rectal microbiota.

Establishment of tongue microbiota by 18 months of age and determinants of its microbial profile

IMPORTANCE

Understanding the development of oral microbiota early in life and the factors that influence it is important for preventing the establishment of dysbiotic oral microbiota later in life. This study demonstrates that the tongue microbiota undergoes early development from 4 to 18 months of age and converges into two types of microbiota showing indications of adult characteristics, with either S. salivarius or Neisseria-dominance. Interestingly, their divergence was strongly determined by their weaning status and the dietary frequencies of sweetened beverages, snacks, and fruits, suggesting that dietary habits during this period might influence the establishment of the oral microbiota. These findings may contribute to the development of novel preventive strategies against oral microbiota-related diseases.

Longitudinal association between periodontal condition and glycaemic status in middle-aged adults: A cross-lagged panel analysis

AIM

To investigate the existence of a bidirectional temporal relationship between periodontal condition and glycaemic status.

MATERIALS AND METHODS

This longitudinal study included 2198 participants with mean age 43.4 ± 7.7 years, who underwent dental examinations in Yokohama, Japan, at two time points, 2003-2004 and 2008-2009, at an interval of 5 years. Periodontal condition was assessed by the mean value of probing pocket depth (PPD) and clinical attachment level (CAL). Glycaemic status was assessed by fasting glucose and glycated haemoglobin (HbA1c).

RESULTS

The cross-lagged panel models showed the effect of HbA1c at baseline on mean PPD at follow-up (β = 0.044, p = .039). There was a marginal effect of fasting glucose on the mean PPD (β = 0.037, p = .059). It was similar to the effect of fasting glucose or HbAlc on mean CAL. However, in the opposite direction, no effect of mean PPD or CAL at baseline on fasting glucose or HbAlc at follow-up was identified.

CONCLUSIONS

This study demonstrated a unidirectional relationship between glycaemic status and periodontal condition. The study population, however, had mostly mild periodontitis. Future studies are needed to investigate the effect of periodontal condition on glycaemic status in patients with severe periodontitis.

High-Resolution Detection of Translocation of Oral Bacteria to the Gut

Ectopic enrichment of oral microbes in the gut is a notable alteration in gut microbial balance. These microbes are likely delivered from the oral cavity with saliva and food; however, evidence of oral-gut microbial transmission is insufficient and needs further investigation. In this observational study, we examined 144 pairs of saliva and stool samples collected from community-dwelling adults to verify the oral-gut microbial link and identify the relevant influencing factors on the increased abundance of oral microbes within the gut. The bacterial composition of each sample was determined using PacBio single-molecule long-read sequencing of the full-length 16S ribosomal RNA gene and amplicon sequence variant (ASV) analysis. Although the bacterial compositions of salivary and gut microbiota were distinctly different, at least 1 ASV was shared between salivary and gut microbiota in 72.9% of subjects. Shared ASVs accounted for 0.0% to 63.1% (median 0.14%) of the gut microbiota in each subject and frequently included abundant Streptococcus salivarius and Streptococcus parasanguinis. Their total relative abundance in the gut was significantly higher in older subjects or those with dental plaque accumulation. The gut microbiota with ≥5% of shared ASVs displayed a higher abundance of Streptococcus, Lactobacillus, and Klebsiella and a lower abundance of Faecalibacterium, Blautia, Megamonas, and Parabacteroides. Our study presents evidence for the translocation of oral bacteria to the gut in community-dwelling adults and suggests that aging and dental plaque accumulation contribute to an increased abundance of oral microbes in the gut, which might be relevant to the compositional shift in the gut commensals.

Association of second-hand smoke exposure, quantified by salivary cotinine, with dental caries in Japanese adolescents

PURPOSE

Second-hand smoke has adverse effects on oral health. This cohort study used a multilevel approach to investigate the association of second-hand smoke exposure, as determined by salivary cotinine level, with dental caries in adolescents.

METHODS

Data from 75 adolescents aged 11 or 12 years and 2,061 teeth without dental caries were analyzed in this study. Annual dental examinations to assess dental caries were conducted between 2018 and 2021. Salivary cotinine and Dentocult SM-Strip level were measured at baseline. Information on the smoking habits of parents, snack frequency, regular dental visits, and use of fluoride toothpaste was collected at baseline from parent-reported questionnaires.

RESULTS

During the 3-year follow-up, dental caries was noted in 21 adolescents and 43 teeth. Participants exposed to parental smoking had higher salivary cotinine levels than those whose parents did not smoke. The multilevel Cox regression model showed that a high salivary cotinine level was associated with the incidence of dental caries, after adjusting for potential confounding factors (hazard ratio, 3.39; 95% confidence interval 1.08-10.69).

CONCLUSION

This study suggests that the risk of dental caries is higher for adolescents who have high salivary cotinine levels attributable to second-hand smoke exposure.

Dietary Problems Are Associated with Frailty Status in Older People with Fewer Teeth in Japan

This study aimed to investigate the association between dietary problems and frailty according to tooth loss in older Japanese people. This cross-sectional study included 160 older people (mean age 82.6 years) from Japan. Frailty status was assessed using the Study of Osteoporotic Fractures (SOF) criteria, which consists of (i) weight loss > 5% in the past year, (ii) inability to perform five chair stands, and (iii) self-perceived reduced energy level. Frailty was defined as the presence of ≥2 items of SOF criteria. Multivariate logistic regression analyses were performed with frailty as the dependent variable and dietary problems as the independent variable, stratified according to having <20 teeth. Low appetite and no enjoyment of eating were associated with frailty after adjusting for covariates in participants with <20 teeth. Dietary problems, including low appetite, eating alone, and negative attitudes toward enjoyment of eating were associated with a self-perceived reduced energy level in participants with <20 teeth. However, this association was not observed in participants with ≥20 teeth. In older people with fewer teeth, dietary problems have been suggested to be associated with frailty. Therefore, it may be necessary to pay attention to dietary problems, especially in older people with tooth loss.

Burden of Oral Diseases and Access to Oral Care in an Ageing Society

Objective

The total years lived with disability among older people, and the concomitant burden of tooth loss in ageing societies have increased. This study is an overview of the burden of oral diseases and access to oral care in an ageing society.

Methods

We selected key issues related to the burden of oral diseases and access to oral care and reviewed the relevant literature.

Results

The rising number of older people with teeth increases their oral health care needs. To improve access to oral care, affordability of care is a great concern with respect to universal health coverage. In addition, accessibility is a crucial issue, particularly for vulnerable older adults. To improve oral care access, attempts to integrate oral health care into general care are being made in ageing countries. For this purpose, provision of professional oral care at home through domiciliary visits and provision of daily oral health care by non-dental professional caregivers are important. Oral health care for older people reduces general diseases such as pneumonia and malnutrition, which in turn could reduce further healthcare costs.

Conclusions

To address the growing burden of oral care in ageing societies, special provision of oral health care to vulnerable older people, and integration of oral care with primary care will be required.

Evaluation of distinct modes of oxidative secondary injury generated in heat-treated cells of Escherichia coli with solid/liquid and complex/semi-synthetic media sets

AIMS

To characterize and evaluate oxidative secondary injury generated in heat-treated Escherichia coli cells during recovery cultivation either on agar or in a broth of a semi-synthetic enriched M9 (EM9) medium and a complex Luria broth (LB) medium with different types of antioxidants.

METHODS AND RESULTS

E. coli cells grown in the EM9 and LB broth were heated at 50^o C in a buffer (pH7.0). Heated cells were recovered on the same kind of agar medium as that used for growth, with or without different antioxidants. Although these antioxidants mostly protected the cells from oxidative secondary injury on the recovery media, sodium thiosulfate and sodium pyruvate were most protective on EM9 and LB agars, respectively. Determination of viability using the most probable number and growth delay analysis methods showed significant reductions in the protective effects of antioxidants in the EM9 and LB media.

CONCLUSION

Oxidative secondary injury generated in heated E. coli cells was found to be qualitatively and quantitatively diverse under cellular and environmental conditions.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results suggest that different modes of oxidation should be considered in viability determination and injured cell enumeration of heat-treated cells.

Yogurt product intake and reduction of tooth loss risk in a Japanese community

Aim

To evaluate the longitudinal association between yogurt product intake and oral health in a population‐based study.

Materials and Methods

This study included 1967 Japanese residents aged 40–79 years who underwent dental examinations in 2012. Among them, 1469 participants were followed up in 2017 for the incidence of tooth loss, which was defined as two or more teeth lost over 5 years. The intake of yogurt products, defined as yogurt and lactic acid beverages, was estimated using a semi‐quantitative food frequency questionnaire. The composition of the salivary microbiota was evaluated.

Results

The Poisson regression model showed that a higher intake of yogurt products was negatively associated with the incidence of tooth loss (p for trend = .020), adjusted for potential confounding factors. Mediation analysis confirmed that periodontal condition partly mediated the effect of yogurt product intake on tooth loss, while dental caries experience did not. Additionally, we confirmed the association of a high intake of yogurt products with a low percentage of the salivary microbiota pattern, which was associated with poor oral health.

Conclusion

These findings suggest that the intake of yogurt products is associated with a lower risk of tooth loss resulting from periodontal disease, probably via modulation of the oral microbiome composition.

Baseline periodontal status and modifiable risk factors are associated with tooth loss over a 10-year period: estimates of population attributable risk in a Japanese community

Background

This study aimed to examine whether modifiable risk factors can predict tooth loss over 10 years and estimate population attributable risk (PAR) for a combination of modifiable factors.

Methods

This longitudinal study included 1466 participants who underwent dental examinations in 2007 and 2017 and were aged 40 to 79 years at baseline. Periodontal conditions were assessed using the 2018 periodontal classification. Incident tooth loss was defined as ≥4 teeth lost over a 10‐year period. We calculated the partial PAR (pPAR%) for tooth loss to estimate the combined effect of modifiable risk factors.

Results

Incidence of tooth loss was 17.5%. Directed acyclic graphs were used to identify risk factors for tooth loss. A logistic regression model showed that baseline periodontitis, dental caries experience, no regular dental visit, periodontal treatment, smoking, and obesity were associated with tooth loss after adjusting for covariates; pPAR% was 55.5% (95% confidence interval: 31.1% to 73.0%) in periodontitis Stage III to IV and 87.6% (50.4% to 97.4%) in the combination of all factors, respectively. The sex‐stratified analysis showed that smoking and no regular dental visit in men and obesity in women were identified as potential risk factors for tooth loss.

Conclusions

Modifiable factors accounted for most cases of incident tooth loss. Risk factors for tooth loss might differ by sex, suggesting that the appropriate approach for preventing tooth loss base on sex.

Periodontal health predicts self-rated general health: A time-lagged cohort study

OBJECTIVES

There is limited evidence of a temporal relationship between periodontal diseases and self-perceived general health. To plug this knowledge gap, we aimed to assess how periodontal health affects future self-rated health (SRH).

METHODS

We collected data from five waves of an annual nationwide Japanese survey of dental patients from 2015 to 2019. The analysis of repeated measurements included 9306 observations from 4242 patients aged 20 years or older. The clinical periodontitis measurements were bleeding on probing, deepest periodontal pocket depth and most severe clinical attachment loss (CAL). We used a self-administered questionnaire to collect data on sociodemographic characteristics, diabetes history, health behaviour, SRH and self-reported periodontitis. We applied 2-level ordered logistic regression models for repeated measurements to examine the relationships between SRH (time t) and 1-year-lagged periodontal health (time t-1) after adjusting for covariates.

RESULTS

The percentage of SRH responses recorded at time t as 'good', 'moderate' and 'poor' were 36.9%, 52.4% and 10.7%, respectively. Multivariate analyses showed that the risk of poorer SRH at time t increased in patients with CAL ≥7 mm (odds ratio [OR] = 1.15, 95% confidence interval [CI] = 1.02-1.30), those who reported bleeding gums (OR = 1.33, 95% CI = 1.21-1.46) and those who perceived swollen gums (OR = 1.40, 95% CI = 1.26-1.56) at time t-1. Sensitivity analyses using the 4-year follow-up model and 3-year-lagged cohort model also showed consistent results.

CONCLUSION

Periodontitis shows a gradual contribution to future SRH in dental patients, even after adjusting for sociodemographic characteristics, general health and health-related behaviours.

10-year trend of tooth loss and associated factors in a Japanese population-based longitudinal study

OBJECTIVES

We examined the trend in the number of missing teeth in a Japanese community over a 10-year period and the potential associated explanatory factors.

DESIGN

Prospective cohort study.

SETTING

A population-based study conducted in 2007, 2012 and 2017 in Japan (Hisayama Study).

PARTICIPANTS

Residents of a Japanese community aged 40-79 years undergoing dental examination in 2007 (n=2665), 2012 (n=2325) and 2017 (n=2285).

OUTCOME MEASURES

The number of missing teeth, periodontal condition, dental caries experience, dental plaque index and oral health behaviours were evaluated each year. The longitudinal analysis of variation in these factors were assessed using mixed models.

RESULTS

The age-adjusted and sex-adjusted mean number of missing teeth decreased with time (6.80 in 2007, 6.01 in 2012 and 4.99 in 2017). The mean clinical attachment level (CAL), prevalence of periodontitis and dental plaque index decreased over the study period, while dental caries experience slightly increased. The level of oral health behaviour increased over time. Poisson mixed models showed that changes in mean CAL and dental caries experience were positively associated with the change in the number of missing teeth over time. Linear mixed models showed that changes in dental plaque index and no regular dental visit were positively associated with changes in mean CAL.

CONCLUSIONS

These findings suggest that a decreasing trend regarding the number of missing teeth in Japan might be associated with improvements in the periodontal condition due to changes in oral hygiene level and oral health behaviour.

Clinical utility of subgingival plaque-specific bacteria in salivary microbiota for detecting periodontitis

Saliva contains diverse bacteria shed from various oral sites, including subgingival plaque. It is reasonable to focus on the total occupancy of subgingival plaque-specific bacteria (SUBP bacteria), which live in subgingival environments, in the saliva for detecting periodontitis using salivary testing. This study aimed to validate the clinical utility of SUBP bacteria in the salivary microbiota for the detection of periodontitis. We examined stimulated saliva samples collected from 125 subjects who visited three dental clinics. The relative abundances of previously identified 11 SUBP bacteria were determined using 16S ribosomal RNA gene sequencing and a reference-based approach. The prediction performance was evaluated using a receiver operating characteristic (ROC) curve. The SUBP bacteria accounted for 0-15.4% of the salivary microbiota, and the percentage distinguished periodontitis patients with at least 15 sites with probing depth ≥4 mm with a sensitivity of 0.90 (95% confidence interval [CI], 0.81-0.98) and specificity of 0.70 (95% CI, 0.60-0.80) (area under the ROC curve [AUC], 0.87). Among 2,047 combinations of 11 SUBP bacteria, combinations including Streptococcus constellatus, Porphyromonas gingivalis, and Fusobacterium nucleatum subsp. vincentii demonstrated significantly higher AUC values in their detection. These results suggest that examining SUBP bacteria in saliva may be useful for detecting periodontitis patients in mass screening.

Number of teeth, denture wearing and cognitive function in relation to nutritional status in residents of nursing homes

BACKGROUND

Although statistical associations between tooth loss and cognitive decline have been reported, there are few previous studies on denture wearing. Additionally, it remains unclear whether nutritional status mediates this association.

OBJECTIVE

Our purpose was to test for the hypothesis that the association between the number of teeth and denture wearing with cognitive function is mediated by nutritional status in residents of nursing homes.

MATERIALS AND METHODS

We enrolled 162 participants who required long-term care (mean age: 87.7 ± 7.5 years, 26 men and 136 women) and were admitted to eight nursing homes in Fukuoka city, from September 2013 to March 2014. A trained dentist conducted dental and swallowing examinations, and the care-staff assessed nutritional status, comorbid conditions and cognitive function using the Clinical Dementia Rating (CDR).

RESULTS

Poisson regression analysis showed that 0-19 teeth without dentures were associated with severe cognitive impairment (CDR 3) (prevalence ratio = 2.00; 95% confidence interval: 1.13-3.55) after adjustment for sex, age, suspected swallowing dysfunction and comorbid conditions. Mediation analysis confirmed that the nutritional status as a mediator of this association (the percentage mediated effect through nutritional status was 23.1%).

CONCLUSION

There is an association between dental status and cognitive impairment in elder individuals, and dentures and poor nutrition are involved in this association. However, due to the cross-sectional design of this study, there is a possibility that this association is bidirectional.

Airflow limitation and tongue microbiota in community-dwelling elderly individuals

Numerous oral indigenous microorganisms are constantly introduced into the stomach via the laryngopharynx, and a portion of these microorganisms irregularly reaches the lower airways and lungs. This study investigated the association between airflow limitation and the status of tongue microbiota, which is a primary source of ingested oral bacterial populations.

The study population consisted of 484 community-dwelling adults aged 70–80 years inhabiting Hisayama town, Japan, who underwent a regular health examination including dental examination and spirometry test in 2016. The bacterial density and composition of their tongue microbiota were determined using a previously used 16S rRNA gene to understand their relationship with oral health conditions. The present cross-sectional study compared the tongue microbiota status between elderly individuals with airflow limitation and those with normal airflow.

The total bacterial density of the tongue microbiota of individuals with airflow limitation was significantly higher than that of individuals with normal airflow. Logistic regression analysis demonstrated that a high-biomass tongue microbiota was significantly associated with airflow limitation after adjustment for smoking intensity and other covariates (adjusted OR 1.61, 95% CI 1.01–2.60). Of the predominant commensals, higher amounts of Prevotella melaninogenica and Actinomyces odontolyticus were associated with a higher prevalence of airflow limitation.

These results indicate that increased bacterial burden in the tongue microbiota is associated with a higher prevalence of airflow limitation.

Bacterial enrichment in the tongue microbiota is associated with airflow limitation characterising COPD in community-dwelling elderly adultshttps://bit.ly/36qMf6G

Multilevel Analysis of the Association of Dental-Hygienist-Related Factors on Regular Dental Check-Up Behavior

Few studies have examined the factors related to dental clinics during dental check-ups. We examined the association between dental-hygienist-related factors and patients’ regular dental check-ups. This nationwide cross-sectional study was based on a survey conducted in Japan in 2014. The analyzed population included 12,139 patients from 1181 dental clinics. We used three-level Poisson regression analysis, considering patient‒clinic‒prefecture, to examine the association of dental-hygienist-related factors with dental check-up behavior. Patients attending treatment and regular check-ups constituted 63.0% and 37.0%, respectively. The adjusted prevalence ratios (PRs) for patients undergoing regular dental check-ups at dental clinics with dedicated dental hygienists’ units, spending ≥20 min in patient education (compared to 0 min), and with three or more dental hygienists (compared to 0 hygienists) available were 1.17 (95% confidence interval [CI]: 1.06–1.30), 1.25 (95%CI: 1.07–1.46), and 2.05 (95%CI: 1.64–2.56), respectively. The median PR indicates that when a patient randomly moves to another dental clinic with more regular dental check-ups, this prevalence increased 1.69 times. These results suggest that dental check-up behavior is determined not only by individual factors but also dental-clinic-level factors. Improving the dental-hygienist-related factors is necessary to encourage people to visit dentists for regular check-ups.

Association between periodontitis and fibrotic progression of non-alcoholic fatty liver among Japanese adults

AIM

Non-alcoholic fatty liver (NAFL) is known to develop into liver fibrosis, which increases the risk of liver cirrhosis and liver cancer. The association between periodontal condition and fibrotic progression of NAFL is unclear. This study aimed to clarify this longitudinal association.

MATERIALS AND METHODS

Among 4812 participants aged 35-64 years undergoing annual health check-ups between 2003 and 2004, and follow-up 5 years later, 392 participants were diagnosed with NAFL. After excluding participants with liver fibrosis at baseline, 341 participants were followed up for 5 years. NAFL disease fibrosis score of ≥-1.455 was used to evaluate the probability of the presence of liver fibrosis.

RESULTS

During the follow-up period, 10.6% of participants progressed to liver fibrosis. A higher clinical attachment level (CAL) tended to be associated with the incidence of liver fibrosis in the logistic regression analysis (odds ratio [OR] 1.82, 95% confidence interval [CI], 0.94-3.49, p = .074). The stratified analysis by obesity revealed a significant association with higher CAL in obese participants (OR 2.87, 95% CI, 1.23-6.69, p = .015), but not in non-obese participants.

CONCLUSION

Higher CAL was associated with an increased probability of liver fibrosis in obese adults with NAFL.

Longitudinal Associations of Toothbrushing With Obesity and Hyperglycemia

Background

Toothbrushing is a health-related lifestyle habit and has been reported to contribute not only to oral health but also to some parameters of general health; however, little research has been conducted to understand the association of the frequency and timing of toothbrushing with the development of comprehensive metabolic abnormalities, with consideration of oral health condition. In this study, using longitudinal data, we examined this association in Japanese adults, adjusting for periodontal condition.

Methods

A 5-year longitudinal study was performed with 4,537 participants between 35 and 64 years old who underwent an annual dental examination in both 2003 and 2008. Data about toothbrushing habits and metabolic abnormalities, such as obesity, hyperglycemia, diabetes, hypertension, hypertriglyceridemia, and low levels of high-density lipoprotein-cholesterol, were analyzed using Poisson regression analysis.

Results

The percentage of participants with a toothbrushing frequency ≤1 time/day was 29.4%, and that for those not brushing their teeth at night was 21.4%. The incidences of obesity and hyperglycemia after 5 years were 5.5% and 28.4%, respectively. A toothbrushing frequency ≤1 time/day was associated with development of obesity (prevalence rate ratio [PRR] 1.77; 95% confidence interval [CI], 1.12–2.80), after adjusting for periodontal condition and potential risk factors. A significant association between not brushing teeth at night and hyperglycemia (PRR 1.30; 95% CI, 1.02–1.66) was observed in participants with toothbrushing frequency of 1 time/day. No association was found between toothbrushing habits and other metabolic abnormalities.

Conclusions

This study suggests that toothbrushing habits are associated with the development of obesity and hyperglycemia.

A multilevel analysis of the importance of oral health instructions for preventing tooth loss: The 8020 Promotion Foundation Study of Japanese Dental Patients

Background

Many studies have reported risk factors for tooth loss. Oral health instruction is considered effective at improving oral health behavior and oral health. However, few studies have examined the relationship of dental clinic factors, such as the number of dental hygienists and implementation of oral health instructions, with tooth loss. Here, we conducted a multilevel analysis to clarify the dental clinic risk factors associated with tooth loss.

Methods

Baseline surveys were conducted at 1216 dental clinics in 46 prefectures in Japan, and 12,399 dental patients aged 20 years and over underwent oral examinations and completed a questionnaire. The dental clinics also completed a questionnaire at baseline. A 3-year follow-up survey included 2488 patients in 585 dental clinics. Multilevel multivariate logistic regression analysis was used to examine the risk of tooth loss at the patient and clinic levels.

Results

Of the patient variables, older age, higher mean probing pocket depth, current or past smoking, and bleeding during tooth brushing were associated with higher risks of tooth loss. Individuals with many teeth who visited dental clinics for maintenance were at significantly lower risk of tooth loss. Of the clinic variables, patients attending dental clinics with four or more dental hygienists had a significantly lower risk of tooth loss (OR 0.68, 95% CI 0.50–0.99). Patients attending dental clinics that provide oral health instructions for 20 min or more had a significantly lower risk of tooth loss (OR 0.69, 95% CI 0.50–0.96).

Conclusions

In addition to individual risk factors for tooth loss, dental clinic factors such as length of oral health instruction and number of dental hygienists are associated with tooth loss. In dental clinics, ensuring sufficient time for dental hygienists to provide oral health instructions can help prevent tooth loss in dental patients.

Association between intensive health guidance focusing on eating quickly and metabolic syndrome in Japanese middle-aged citizens

PURPOSE

The purpose of this intervention study was to investigate whether intensive health guidance focusing on eating quickly can prevent metabolic syndrome (MetS) more effectively than standard routine guidance in Japanese citizens living in rural areas.

METHODS

This controlled, non-randomized, intervention study analyzed 141 participants with MetS at baseline. Participants in the intervention group received health guidance focusing on eating quickly and standard health guidance about MetS in accordance with the guidelines of the Ministry of Health, Labour and Welfare in Japan, whereas participants in the control group received only standard health guidance about MetS. The primary study outcome was the prevalence of MetS at a 1-year follow-up.

RESULTS

At 1-year follow-up, the prevalence of MetS in the intervention group was significantly lower than that in the control group (p = 0.003). The decreases in body weight, body mass index, waist circumference and triglycerides from baseline to 1 year were significantly greater in the intervention group than in the control group (p < 0.05).

CONCLUSION

Intensive health guidance focusing on eating quickly is more effective for improving MetS than standard Japanese health guidance alone.

LEVEL OF EVIDENCE

Level II, Evidence obtained from well-designed controlled trials without randomization. TRIAL REGISTRY NAME, REGISTRATION IDENTIFICATION NUMBER, AND URL FOR THE REGISTRY: UMIN, UMIN000030600, http://www.umin.ac.jp/ctr/index-j.htm.

Periodontal status and self-reported systemic health of periodontal patients regularly visiting dental clinics in the 8020 Promotion Foundation Study of Japanese Dental Patients

This nationwide cross-sectional survey investigated the association between periodontal disease and self-reported systemic health in periodontal patients who regularly visited private dental clinics in Japan. Data from 999 patients of 444 dental clinics were analyzed; the patients were aged 40 years or older, regularly visited dentists, and had diagnosed periodontal disease (defined as two or more teeth with a clinical attachment level ≥6 mm). Medical history was collected with a self-reported questionnaire. Number of teeth with a probing pocket depth (PPD) ≥5 mm was used to define periodontal status, and the highest quartile was used as the dependent variable. A Poisson regression model showed that histories of diabetes and hypertension were associated with a larger number of teeth with a PPD ≥5 mm (diabetes: prevalence rate ratio [PRR] 1.36, 95% confidence interval [CI] 1.00-1.85; hypertension: PRR 1.27, 95% CI 1.02-1.58) after adjusting for potential periodontal risk factors. These findings suggest that diabetes and hypertension are associated with worse periodontal disease. Dentists should confirm the diabetes and hypertension status of patients who receive maintenance care, because these conditions could affect periodontal management of patients.

Relationships of Variations in the Tongue Microbiota and Pneumonia Mortality in Nursing Home Residents

Background

Aspiration of oral debris, containing dense oral bacteria, is a major cause of pneumonia in elderly adults. This study investigated the relationship between tongue microbiota composition and incidence of pneumonia-related deaths, in nursing home residents.

Methods

The subjects were assessed for health conditions, including their tongue microbiota, at baseline. We determined tongue microbiota profiles by 16S ribosomal RNA gene sequencing and clustering approach. All subjects (n = 173) were followed prospectively for a median of 19 months to assess the incidence of all-cause death, including pneumonia-related death. We evaluated risk estimates of microbiota effects on death using multivariate Cox proportional hazards regression analysis.

Results

Tongue microbiota were classified into two community types: type I was dominated by Prevotella and Veillonella species, while type II was dominated by Neisseria and Fusobacterium species. The subjects with type I microbiota exhibited a significantly greater risk of all-cause death (adjusted hazard ratio [aHR] = 3.79, 95% confidence interval [CI] = 1.38-10.39) and pneumonia-related death (aHR = 13.88, 95% CI = 1.64-117.21), than those with type II microbiota. There was no significant association between microbiota type and other-cause death.

Conclusions

The tongue microbiota type was significantly associated with an increased mortality risk from pneumonia in nursing home residents.

Characteristics of the Salivary Microbiota in Patients With Various Digestive Tract Cancers

The salivary microbiota is constantly swallowed and delivered to the digestive tract. These bacteria may be associated with gastrointestinal diseases. This case-control study examined the salivary microbiota in patients with digestive tract cancer (DTC) and evaluated their differential distribution based on the cancer sites. We collected saliva samples from 59 patients with cancer in any part of the digestive tract (tongue/pharynx, esophagus, stomach, and large intestine) and from 118 age- and sex-matched control subjects. There was no significant difference in periodontal status between DTC patients and control subjects (P = 0.72). We examined the bacterial diversity and composition in saliva by 16S ribosomal RNA gene sequencing. Salivary bacterial diversity in DTC patients was significantly higher than that in control subjects [number of operational taxonomic units (OTUs), P = 0.02; Shannon index, P < 0.01; Chao1, P = 0.04]. Eleven differentially abundant OTUs in DTC patients were identified using the linear discriminant analysis effect size (LEfSe) method. Based on the cancer sites, the diversity of salivary bacteria was especially higher in tongue/pharyngeal or esophageal cancer patients than in control subjects. Among the 11 differentially abundant OTUs in DTC patients, an OTU corresponding to Porphyromonas gingivalis was more abundant in the saliva of all groups of DTC patients compared to that in control subjects, and an OTU corresponding to Corynebacterium species was more abundant in all groups other than gastric cancer patients (P < 0.01). In addition, the relative abundances of OTUs corresponding to Fusobacterium nucleatum, Streptococcus parasanguinis II, and Neisseria species were significantly higher in tongue/pharyngeal cancer patients compared to their abundances in control subjects (P < 0.01). The relative abundance of an OTU corresponding to the Neisseria species was also significantly higher in gastric cancer patients and that of an OTU corresponding to Actinomyces odontolyticus was significantly higher in colorectal cancer patients (P < 0.01). These results suggest that the salivary microbiota might be associated with various digestive tract cancers.

Periodontitis Is Associated with Chronic Obstructive Pulmonary Disease

Although they are known to share pathophysiological processes, the relationship between periodontitis and chronic obstructive pulmonary disease (COPD) is not fully understood. The aim of the present study was to test the hypothesis that periodontitis is associated with a greater risk of development of COPD, when smoking is taken into account. The analysis in a 5-y follow-up population-based cohort study was based on 900 community-dwelling Japanese adults (age: 68.8 ± 6.3 [mean ± SD], 46.0% male) without COPD aged 60 or older with at least 1 tooth. Participants were classified into 3 categories according to baseline periodontitis severity (no/mild, moderate, and severe). COPD was spirometrically determined by a fixed ratio of <0.7 for forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) and by FEV1/FVC below the lower limit of normal. Poisson regression was used to calculate the relative risk (RR) of developing COPD according to the severity of periodontitis. The population attributable fraction (PAF) was also calculated. During follow-up, 22 (2.4%) subjects developed COPD. Compared with no/mild periodontitis subjects, a significantly increased risk of COPD occurred among severe periodontitis subjects (RR = 3.55; 95% confidence interval [CI], 1.18 to 10.67), but no significant differences were observed between the no/mild and moderate categories (RR = 1.48; 95% CI, 0.56 to 3.90). After adjustment for potential confounders, including smoking intensity, the relationship between severe periodontitis and risk of COPD remained significant (RR = 3.51; 95% CI, 1.15 to 10.74). Likewise, there was a positive association of periodontitis severity with risk of COPD ( P for trend = 0.043). The PAF for COPD due to periodontitis was 22.6%. These data highlight the potential importance of periodontitis as a risk factor for COPD.

Risk factors for tooth loss in adult Japanese dental patients: 8020 Promotion Foundation Study

AIM

The assessment of the risk of tooth loss in patients visiting a dental clinic is important for managing their oral health. In the present study, we examined the risk factors for tooth loss among dental patients.

METHODS

Data from the 8020 Promotion Foundation Study on the Health Promotion Effects of Dental Care were used in the present study. The study involved 2743 patients who visited a dental clinic in Japan and completed a questionnaire and oral health examination at baseline and at the 2-year follow up. Tooth- and person-level risk factors for tooth loss during 2 years were subjected to a multilevel multivariate logistic regression analysis.

RESULTS

In both the person- and tooth-level analyses, age, smoking habit, reason for dental visit, economic status, number of remaining teeth, and periodontal status were significantly associated with tooth loss. In the tooth-level analysis, tooth type, tooth status, and periodontal status were significantly related to tooth loss. Persons who visited a dental clinic for periodic maintenance had a significantly lower risk of tooth loss than those who visited only to receive dental treatment.

CONCLUSIONS

Various tooth-level factors and modifiable factors, such as smoking cessation and periodic maintenance, are important for the suppression of tooth loss in dental patients.

Periodontal status and lung function decline in the community: the Hisayama study

This study aimed to determine whether periodontal status is related to a decline in lung function in a general Japanese population. We followed a total of 1,650 community-dwelling individuals (≥40 years) without chronic obstructive pulmonary disease, with at least one teeth, for 3 years. Periodontal status was assessed at baseline by clinical attachment loss (CAL) and probing pocket depth (PPD) at two sites for each tooth, and the mean values were calculated for each subject. Lung function was measured at baseline and follow-up using spirometry, and longitudinal decline in forced expiratory volume in one second (FEV1) was calculated. Multivariate Poisson regression with robust error variance was used to estimate risk ratio (RR). After adjusting for potential confounders including smoking status, there was a tendency for the adjusted RR of developing rapid lung function decline (≥160 mL/3years, the highest quartile of the distribution of FEV1 declines) to increase as mean CAL levels increased (P trend = 0.039). Likewise, a positive association was observed between mean PPD levels and RR of developing rapid lung function decline (P trend = 0.047). Our findings suggest deterioration of periodontal status could be a risk factor for rapid lung function decline in the general Japanese population.

Decreased cognitive function is associated with dysphagia risk in nursing home older residents

OBJECTIVE

To examine the association between cognitive function and dysphagia risk among Japanese nursing home residents.

BACKGROUND

Reduction in cognitive function can influence the intake of food during swallowing, and may be an aggravating factor in dysphagia.

METHODS

This cross-sectional study included 236 residents aged ≥60 years from eight nursing homes. Screening of dysphagia, especially aspiration risk, was conducted using the Modified Water Swallow Test, whose scores from one to three were classified as at risk of dysphagia. Cognitive function was evaluated using Mini-Mental State Examination (MMSE). Number of teeth and occlusal support were evaluated by clinical examination. The participants were stratified into dentulous and edentulous groups, because the number of teeth could influence swallowing function. The odds ratio (OR) and 95% confidence interval (CI) for dysphagia risk based on the scores of MMSE were calculated using logistic regression. Demographic characteristics, activity of daily living, comorbidities, health behaviour and occlusal support were used as covariates.

RESULTS

Among the 236 participants (111 dentulous participants and 125 edentulous participants) included in our analysis, 16.9% belonged to risk of dysphagia. Dentulous participants with higher scores of MMSE tended to have significantly lower odds of dysphagia risk after adjusting for covariates (OR = 0.87, 95% CI = 0.80-0.96). Despite the lack of significant differences, edentulous participants with higher score of MMSE tended to have lower odds of dysphagia risk (OR = 0.92, 95% CI = 0.83-1.00).

CONCLUSION

Decreased cognitive function may be an independent predictor of dysphagia among dentulous and edentulous adults.

Relationship of toothbrushing to metabolic syndrome in middle-aged adults

AIM

To examine the effect of toothbrushing on the development of metabolic syndrome (MetS), including assessment of periodontal status, in middle-aged adults.

METHODS

This 5-year follow-up retrospective study was performed in 3,722 participants (2,897 males and 825 females) aged 35-64 years who underwent both medical check-ups and dental examinations. Metabolic components included obesity, elevated triglycerides, blood pressure, fasting glucose and reduced high-density lipoprotein. Toothbrushing frequency was assessed using a questionnaire. Periodontal disease was defined as having at least one site with a pocket depth of ≥4 mm. Logistic regression analysis was performed to evaluate the relationship between toothbrushing frequency at the baseline examination and the development of MetS (≥3 components).

RESULTS

During follow-up, 11.1% of participants developed MetS. After adjusting for potential confounders including periodontal disease, participants with more frequent daily toothbrushing tended to have significantly lower odds of developing MetS (p for trend = .01). The risk of development of MetS was significantly lower in participants brushing teeth ≥3 times/day than in those brushing teeth ≤1 time/day (odds ratio = 0.64, 95% confidence interval = 0.45-0.92).

CONCLUSIONS

Frequent daily toothbrushing was associated with lower risk of development of MetS.

Tooth loss, swallowing dysfunction and mortality in Japanese older adults receiving home care services

AIM

Severe tooth loss and swallowing dysfunction occur more frequently in dependent older adult populations. Poor oral health and functional status are expected to have a negative impact on general health. We examined whether mortality is related to the number of teeth and swallowing function in dependent older Japanese individuals receiving home care services.

METHODS

Older adults aged ≥65 years who were receiving home care were included. The planned follow-up period was 3 years. Baseline data on the number of teeth, swallowing function, nutritional status, cognitive ability and activities of daily living were collected.

RESULTS

A total of 259 participants (mean age 85.0 ± 7.7 years) were enrolled. The mean length of follow up was 26.2 months. Severe tooth loss (≤9 present teeth) and swallowing dysfunction were observed in 68.0% and 32.0% of the participants, respectively. Cox's proportional hazards regression model showed that participants with both ≤9 teeth and swallowing dysfunction were at a higher risk of mortality compared with those with both ≥10 teeth and normal swallowing function (hazard ratio 2.89, 95% confidence interval 1.22-6.83). A significant interaction among severe tooth loss, swallowing dysfunction and mortality risk was observed.

CONCLUSIONS

Severe tooth loss and swallowing dysfunction were associated with increased mortality. The present study suggests that the maintenance of oral health and swallowing function has a positive effect on general health. Therefore, attention should be given to both tooth loss and swallowing function in dependent older adult populations. Geriatr Gerontol Int 2018; 18: 873-880.

Oral mycobiome in community-dwelling elderly and its relation to oral and general health conditions

OBJECTIVE

Oral fungal infection is generally associated with dysbiosis related to antibiotic use, immunodeficiency, or frailty. However, fungal colonization in a typical population without apparent symptoms and its associated conditions are poorly understood. In this study, oral fungal colonization in community-dwelling and independently living elderly populations was evaluated and factors affecting fungal colonization were analyzed.

SUBJECTS AND METHODS

The subjects (410; 181 males and 229 females) were 75-99 years of age; those under prior antibiotic use were excluded. Fungal populations in the saliva were evaluated by PCR-based molecular techniques. Body mass index (BMI), smoking habits, and oral health conditions were examined.

RESULTS

Salivary fungal amounts exceeded 10⁴  CFU/ml in 63 (15.4%) of 410 subjects. Candida albicans was most frequently detected (98.4%), followed by Candida glabrata (54.0%), and Candida dubliniensis (38.1%) in those subjects with fungi at 10⁴  CFU/ml or over. Fungi at 10⁴  CFU/ml or over in the presence of C. glabrata or C. dubliniensis was significantly associated with low BMI.

CONCLUSIONS

Candida albicans, C. glabrata, and C. dubliniensis dominated the oral mycobiome in Japanese community-dwelling elderly. Lower BMI might signify compromised health status and thus could result in susceptibility to specific candidiasis by C. glabrata and C. dubliniensis.

Tooth Loss and Risk of Dementia in the Community: the Hisayama Study

OBJECTIVES

To clarify the effect of tooth loss on development of all-cause dementia and its subtypes in an elderly Japanese population.

DESIGN

Prospective cohort study.

SETTING

The Hisayama Study, Japan.

PARTICIPANTS

Community-dwelling Japanese adults without dementia aged 60 and older (N = 1,566) were followed for 5 years (2007-2012).

MEASUREMENTS

Participants were classified into four categories according to baseline number of remaining teeth (≥20, 10-19, 1-9, 0). The risk estimates of the effect of tooth loss on the development of all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD) were computed using a Cox proportional hazards model.

RESULTS

During follow-up, 180 (11.5%) subjects developed all-cause dementia; 127 (8.1%) had AD, and 42 (2.7%) had VaD. After adjusting for potential confounders, there was a tendency for the multivariable-adjusted hazard ratio of all-cause dementia to increase with decrease in number of remaining teeth (P for trend = .04). The risk of all-cause dementia was 1.62 times as great in subjects with 10 to 19 teeth, 1.81 times as great in those with one to nine teeth, and 1.63 times as great in those with no teeth as in those with 20 teeth or more. An inverse association was observed between number of remaining teeth and risk of AD (P for trend = .08), but no such association was observed with risk of VaD (P for trend = .20).

CONCLUSION

Tooth loss is associated with an increased risk of all-cause dementia and AD in the Japanese population.

Association of periodontal status with liver abnormalities and metabolic syndrome

Although an association between periodontal status and liver abnormalities has been reported, it has not been described in relation to metabolic syndrome (MetS), which often coexists with non-alcoholic fatty liver disease. We examined the association of a combination of liver abnormality and MetS with periodontal condition in Japanese adults, based on the level of alcohol consumption. In 2008, 4,207 males aged 45.4 ± 8.9 years and 1,270 females aged 45.9 ± 9.7 years had annual workplace health check-ups at a company in Japan. Periodontal status was represented as periodontal pocket depth at the mesio-buccal and mid-buccal sites for all teeth. Alanine aminotransferase (ALT), and metabolic components were examined. Multiple linear regression analysis showed a significant association between deep pocket depth and the coexistence of elevated ALT and MetS in males with low alcohol consumption. Females showed no such relationship. In conclusion, the association between periodontal condition and the combination of elevated ALT and MetS was confirmed in males. That is, a clear association between liver abnormalities and periodontal condition was seen in male subjects with no or low alcohol consumption and MetS, providing new insights into the connection between liver function and periodontal health.

Tooth loss and metabolic syndrome in middle-aged Japanese adults

AIM

Metabolic syndrome is associated with periodontal disease and dental caries; however, little attention has been given to the association between metabolic syndrome and tooth loss, which is the endpoint of these two diseases. This study examined this association in middle-aged adults over a 5-year period.

METHODS

A retrospective study was performed in 2107 participants (1718 males and 389 females) aged 35-60 years who underwent annual dental check-ups, to evaluate tooth loss and metabolic components, including obesity, elevated triglycerides, blood pressure, fasting glucose, and reduced high-density lipoprotein. Logistic regression analysis was performed to evaluate the association between metabolic syndrome (≥3 components) at the baseline examination and tooth loss.

RESULTS

Over a 5-year period, 10.8% of the participants lost at least one tooth. Compared to those with no metabolic components, participants with ≥3 components had an increased risk of tooth loss (odds ratio = 1.54; 95% confidence interval: 1.01-2.37), adjusting for age, gender, dental caries experience, attachment loss, oral hygiene status, number of teeth, tooth brushing frequency, smoking, and occupational status.

CONCLUSIONS

Metabolic syndrome was associated with the incidence of tooth loss among middle-aged adults.

Swallowing Function and Nutritional Status in Japanese Elderly People Receiving Home-care Services: A 1-year Longitudinal Study

OBJECTIVES

Malnutrition is a serious health concern for frail elderly people. Poor oral function leading to insufficient food intake can contribute to the development of malnutrition. In the present study, we explored the longitudinal association of malnutrition with oral function, including oral health status and swallowing function, in elderly people receiving home nursing care.

DESIGN

Prospective observational cohort study with 1-year follow-up.

SETTING

Two mid-sized cities in Fukuoka, Japan from November 2010 to March 2012.

PARTICIPANTS

One hundred and ninety-seven individuals, aged ≥ 60 years, living at home and receiving home-care services because of physical disabilities, without malnutrition.

MEASUREMENTS

Oral health status, swallowing function, taking modified-texture diets such as minced or pureed foods, nutritional status, cognitive function, and activities of daily living were assessed at baseline. The associations between malnutrition at 1-year follow-up and these related factors were analyzed using a logistic regression model.

RESULTS

Swallowing disorders [risk ratio (RR): 5.21, 95% confidence interval (95% CI): 1.65-16.43] were associated with malnutrition. On the other hand, oral health status did not have a direct association with malnutrition.

CONCLUSION

Swallowing disorders may be associated with the incidence of malnutrition in elderly people receiving home-care. The findings indicate that maintaining swallowing function may contribute to the prevention of malnutrition in frail elderly people.