The Alteration of Brain Function by the Improvement of Periodontal Tissues and Occlusal State.

Objective: In this study, we have introduced a case in which the effective blood oxygenation level-dependent signal on functional magnetic resonance imaging (fMRI) was altered by the improvement of periodontal tissue and occlusal function in a patient with periodontitis Stage II Grade B. Material and Methods. A 61-year-old female patient requiring periodontal treatment was diagnosed as having periodontitis Stage II Grade B via clinical and radiographic examinations. Her past medical history included type 2 diabetes, hypertension, and hyperlipidemia. Following the patient's informed written consent, the periodontal initial treatment provided to the patient included tooth brushing instruction and scaling and root planing; however, occlusal adjustment was not performed at this stage. Occlusal force and fMRI results were also evaluated at the initial and reevaluation examinations. Results: After the periodontal initial treatment had been performed, it was noted that the patient's periodontal tissue and occlusal force had improved. It was also evident from fMRI that cerebral blood flow had been activated in the insula, primary motor cortex, and premotor cortex. Conclusion: This result suggested that the periodontal ligament had recovered and the periodontal ligament neuron had been further subjected to clenching in the insula so that the muscle spindle sensation impacted the motor cortex.

Wear of Polymer-Infiltrated Ceramic Network Materials against Enamel.

Polymer-infiltrated ceramic network materials (PICNs) have high mechanical compatibility with human enamel. However, the wear properties of PICN against natural human enamel have not yet been clarified. We investigated the in vitro two-body wear behaviors of PICNs and an enamel antagonist. Two PICNs were used: Experimental PICN (EXP) prepared via the infiltration of methacrylate-based resin into the porous silica ceramic network and commercial Vita Enamic (ENA). Two commercial dental ceramics, lithium disilicate glass (LDS) and zirconia (ZIR), were also characterized, and their wear performance was compared to PICNs. The samples were subjected to Vickers hardness tests and two-body wear tests that involve the samples being cyclically impacted by enamel antagonists underwater at 37 °C. The results reveal that the Vickers hardness of EXP (301 ± 36) was closest to that of enamel (317 ± 17). The volumetric wear losses of EXP and ENA were similar to those of LDS but higher than that of zirconia. The volumetric wear loss of the enamel antagonist impacted against EXP was moderate among the examined samples. These results suggest that EXP has wear behavior similar to that of enamel. Therefore, PICNs are mechanically comparable to enamel in terms of hardness and wear and are excellent tooth-restoration materials.

Castable polymer-infiltrated ceramic network composite for training model tooth with compatible machinability to human enamel.

This study aimed to develop a novel polymer-infiltrated ceramic network (PICN) composite fabricated via a slip-casting method for a dental training model tooth with machinability compatible to human enamel. A PICN model tooth comprised of silica/acrylic-resin was fabricated via the slip-casting method. A commercial resin-based model tooth and human enamel were used as the control sample. The samples were evaluated based on Vickers hardness, inorganic contents, density, and machinability. The machinability was characterized by a grinding amount obtained from the grinding test using a device equipped with a dental micromotor handpiece with a diamond bur. The properties of the PICN model tooth yielded a silica content of 84.7% and a density of 1.99 g/cm3, and its Vickers hardness (312) was comparable with that of enamel (348). The grinding amount was comparable with that of enamel. The castable PICN model tooth was compatible to enamel in terms of hardness and machinability.

Relationship between Dynamics of TNF-α and Its Soluble Receptors in Saliva and Periodontal Health State.

Soluble tumor necrosis factor receptors 1 and 2 (sTNF-R1 and sTNF-R2) are reported to protect against excessive TNF-α, a primary mediator of systemic responses to infection. This study aimed to investigate the levels of TNF-α, sTNF-R1, and sTNF-R2 in saliva and to verify whether their dynamics are associated with periodontal health. The study population comprised 28 adult patients. Probing pocket depth, clinical attachment level, and bleeding on probing were assessed, and periodontal inflamed surface area (PISA) was calculated. Stimulated saliva was collected before the oral examinations. The levels of TNF-α, sTNF-R1, sTNF-R2, and total protein (TP) in saliva samples were determined. There were significant positive correlations between TNF-α, sTNF-R1, and sTNF-R2 to TP (/TP) in stimulated saliva. Moreover, there were significant positive correlations between PISA and sTNF-R2/TP. Stepwise multiple regression analysis revealed that PISA was significantly associated with sTNF-R2/TP in saliva; however, TNF-α/TP was not significantly associated with PISA. In conclusion, this study demonstrates that significant relationships exist between the salivary levels of TNF-α and sTNF-R1, and that salivary sTNF-R2 is associated with the expansion of inflamed periodontal tissue.

Effect of COVID-19 on dental telemedicine in Japan.

BACKGROUND/PURPOSE: In Japan, medical and dental care is provided by the universal health insurance system. The Ministry of Health, Labour, and Welfare (MHLW) in Japan sets the rules for health care services provided by health insurance. The MHLW issued a notice in 2020 permitting telemedicine and dental telemedicine for the first visit and for follow-up visits to prevent the spread of COVID-19 infection. We conducted this study to clarify the status of dental telemedicine during 2020. MATERIALS AND METHODS: We used data from lists obtained on the MHLW website in the analysis. We investigated the number of dental institutions conducing dental telemedicine for the first visit and for follow-up visits by prefecture. RESULTS: In each prefecture, fewer dental institutions conducted telemedicine for the first visit than for follow-up visits. Regions with large metropolitan areas had higher numbers of dental institutions conducting dental telemedicine for the first visit and follow-up visits. Private dental clinics provided the largest proportion of dental telemedicine for the first visit, and general hospitals provided the largest proportion for follow-up visits. CONCLUSION: Our study findings indicated that many dental institutions in Japan made efforts to provide dental services via dental telemedicine using the telephone or online with video to help prevent the spread of COVID-19 infection. Dental telemedicine can help patients to access dental services and dental care, thereby expanding the potential of dental telemedicine in Japan.

Periodontal disease and pneumonia mortality in haemodialysis patients: A 7-year cohort study.

AIM: To evaluate the association between periodontal disease and pneumonia mortality in haemodialysis patients. MATERIALS AND METHODS: This prospective cohort study included 211 patients (mean age, 64.4 years) undergoing haemodialysis at a single medical centre. The patients underwent a baseline clinical dental examination in 2008 and were then followed up until July 2015. Periodontal disease was defined as the presence of clinical attachment loss of ≥4 mm in ≥30% of the probed sites. The primary endpoint, that is death from pneumonia, was determined by reviewing death certificates and was analysed using the competing-risks regression model. RESULTS: At baseline, 92 patients (43.6%) had periodontal disease. The median follow-up period was 84 months (interquartile range, 36-86 months). Of the 68 deaths that occurred, 21 were from pneumonia. The multivariable competing-risks regression model showed that periodontal disease was significantly associated with death from pneumonia (adjusted subhazard ratio, 3.49; 95% confidence interval, 1.14-10.64), after adjusting for other baseline health characteristics. CONCLUSIONS: The results of this study suggest that periodontal disease is independently associated with pneumonia mortality in haemodialysis patients. Future studies evaluating the potential effect of oral interventions for periodontal health improvement on pneumonia in haemodialysis patients would be of great interest.

ADAM17 regulates TNF-α expression upon lipopolysaccharide stimulation in oral keratinocytes.

A disintegrin and metalloprotease 17 (ADAM17) is a tumor necrosis factor (TNF)-converting enzyme and was first identified as the enzyme that cleaves the prodomain of TNF-α, a proinflammatory cytokine that plays a central role in immune regulation and a variety of inflammatory responses in destructive periodontal disease. The aim of the present study was to verify the presence of ADAM17 in the gingival epithelium and elucidate its involvement in the release of TNF-αin oral keratinocytes. Immunohistochemical analyses of ADAM17 were performed in gingival tissues obtained from patients and in human oral keratinocytes (HOKs). Additionally, levels of TNF-α and ADAM17 in HOKs exposed to lipopolysaccharide (LPS) were assessed using enzyme-linked immunosorbent assays. Moreover, the effects of ADAM17 inhibitor, matrix metalloproteinase (MMP) inhibitor, and ADAM17 siRNA on TNF-α concentration were assessed. Strong immunoreactivity for ADAM17 was observed in the epithelium of the inflamed gingival tissues and in HOKs. Furthermore, treatment with either ADAM17 inhibitor or ADAM17 siRNA inhibited the generation of TNF-α induced by LPS in HOKs. The present study demonstrates that ADAM17 is strongly expressed in the epithelium of gingival tissues and suggests that ADAM17 may be a key enzyme that regulates the generation of TNF-α in oral keratinocytes.

Relationships between pathologic subjective halitosis, olfactory reference syndrome, and social anxiety in young Japanese women.

BACKGROUND: Pathologic subjective halitosis is known as a halitosis complaint without objective confirmation of halitosis by others or by halitometer measurements; it has been reported to be associated with social anxiety disorder. Olfactory reference syndrome is a preoccupation with the false belief that one emits a foul and offensive body odor. Generally, patients with olfactory reference syndrome are concerned with multiple body parts. However, the mouth is known to be the most common source of body odor for those with olfactory reference syndrome, which could imply that the two conditions share similar features. Therefore, we investigated potential causal relationships among pathologic subjective halitosis, olfactory reference syndrome, social anxiety, and preoccupations with body part odors. METHODS: A total of 1360 female students (mean age 19.6 ± 1.1 years) answered a self-administered questionnaire regarding pathologic subjective halitosis, olfactory reference syndrome, social anxiety, and preoccupation with odors of body parts such as mouth, body, armpits, and feet. The scale for pathologic subjective halitosis followed that developed by Tsunoda et al.; participants were divided into three groups based on their scores (i.e., levels of pathologic subjective halitosis). A Bayesian network was used to analyze causal relationships between pathologic subjective halitosis, olfactory reference syndrome, social anxiety, and preoccupations with body part odors. RESULTS: We found statistically significant differences in the results for olfactory reference syndrome and social anxiety among the various levels of pathologic subjective halitosis (P < 0.001). Residual analyses indicated that students with severe levels of pathologic subjective halitosis showed greater preoccupations with mouth and body odors (P < 0.05). Bayesian network analysis showed that social anxiety directly influenced pathologic subjective halitosis and olfactory reference syndrome. Preoccupations with mouth and body odors also influenced pathologic subjective halitosis. CONCLUSIONS: Social anxiety may be a causal factor of pathologic subjective halitosis and olfactory reference syndrome.

Periodontitis and health-related quality of life in hemodialysis patients.

Periodontitis is common among dialysis patients. The current cross-sectional study aimed to explore associations between periodontitis and health-related quality of life (HRQoL) among hemodialysis patients. Data from 188 dentate patients undergoing hemodialysis between May and July 2008 at a medical center in Kitakyushu city, Japan, were analyzed while applying modified Centers for Disease Control and Prevention/American Academy of Periodontology periodontitis case definitions to categorize the participants into the following three groups: severe, moderate, and no/mild periodontitis, respectively. HRQoL was assessed by the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) where a higher score indicates better health status. Associations between periodontitis groups and the eight health domains of SF-36 were evaluated using general linear models that were adjusted for age, sex, underlying cause of dialysis, duration of dialysis, comorbidities, serum biomarkers, body mass index, smoking status, and alcohol use. Among the 188 participants, 18 (9.6%) had severe periodontitis, 100 (53.2%) had moderate periodontitis, and the remaining 70 (37.2%) had no/mild periodontitis. Compared with the participants with no/mild periodontitis, those with severe periodontitis had worse scores in the following five of eight SF-36 health scales: physical functioning, role physical, vitality, social functioning, and mental health (P < 0.05). The findings suggest an independent relationship between severe periodontitis and decreased HRQoL among dialysis patients.

Cognitive function and 10 year mortality in an 85 year-old community-dwelling population.

The relationship between mortality and impaired cognitive function has not been thoroughly investigated in a very elderly community-dwelling population, and little is known about the association of disease-specific mortality with Mini-Mental State Examination (MMSE) subscale scores. Here we evaluated these data in Japanese community-dwelling elderly. In 2003, 85 year-olds (n=207) were enrolled; 205 completed the MMSE for cognitive function and were followed-up for 10 years, during which time 120 participants died, 70 survived, and 17 were lost to follow-up. Thirty-eight deaths were due to cardiovascular disease, 22 to senility, 21 to respiratory disease, and 16 to cancer. All-cause mortality decreased by 4.3% with a 1-point increase in the global MMSE score without adjustment, and it decreased by 6.3% with adjustment for both sex and length of education. Cardiovascular mortality decreased by 7.6% and senility mortality decreased by 9.2% with a 1-point increase in the global MMSE score with adjustment for sex and education. No association was found between respiratory diseases or cancer mortality and global MMSE score. All-cause mortality also decreased with increases in MMSE subscale scores for time orientation, place orientation, delayed recall, naming objects, and listening and obeying. Cardiovascular mortality was also associated with the MMSE subscale of naming objects, and senility mortality was associated with the subscales of time orientation and place orientation. Thus, we found that impaired cognitive function determined by global MMSE score and some MMSE subscale scores were independent predictors of all-cause mortality or mortality due to cardiovascular disease or senility in 85 year-olds.

Serum total cholesterol concentration and 10-year mortality in an 85-year-old population.

Little is known about the association between total cholesterol (TC) and all-cause mortality in the elderly (especially the very elderly). Here we examined the association between TC and all-cause mortality in 207 very elderly (85-year-old) participants. In 2003, we performed a baseline laboratory blood examination, and blood pressure (BP) and body mass index (BMI) measurements, and lifestyle questionnaires were completed by the participants. The participants were followed for the subsequent 10 years. As of 2013, of the 207 participants in 2003, 70 participants had survived, 120 individuals had died, and 17 were lost to follow up. The TC values were divided into high-TC (≥209 mg/dL), intermediate-TC (176-208 mg/dL), and low-TC (≤175 mg/dL) categories. With the Kaplan-Meier method, we found that both the high-TC and intermediate-TC participants survived longer than the low-TC participants. The men with high TC survived longer than those with low TC, but no corresponding difference was found for the women. A multivariate Cox proportional hazards regression model, with adjustment for gender, smoking, alcohol intake, history of stroke or heart disease, serum albumin concentration, BMI, and systolic BP, revealed that the total mortality in the low-TC group was 1.7-fold higher than that in the high-TC group. Mortality, adjusted for the same factors, decreased 0.9% with each 1 mg/dL increase in the serum TC concentration and decreased 0.8% with each 1 mg/dL increase in the serum (low-density lipoprotein) LDL-cholesterol (LDL-C) concentration. Our results indicate an association between lower serum TC concentrations and increased all-cause mortality in a community-dwelling, very elderly population. Mortality decreased with the increases in both TC and LDL-C concentrations, after adjustment for various confounding factors. These findings suggest that low TC and low LDL-C may be independent predictors of high mortality in the very elderly.

Prevalence and imaging characteristics of detectable tonsilloliths on 482 pairs of consecutive CT and panoramic radiographs.

BACKGROUND: Recent studies suggest that tonsilloliths are clinically related to halitosis and tonsillar abscess. Based on our empirical knowledge, tonsilloliths are relatively commonly encountered in daily clinical practice. It has been reported that the detection rate of tonsilloliths was under 24% in previous reports, although experience suggests otherwise. The purpose of the study was to evaluate the prevalence and characteristics of tonsilloliths using computed tomography (CT). In addition, the possible causes of low detection rates on panoramic radiographs were evaluated based on comparisons between CT images and panoramic radiographs in order to elucidate the limitations of visualizing the area around the palatine tonsils on panoramic radiographs. METHODS: 482 pairs of CT images and panoramic radiographs were retrospectively assessed with respect to the presence and characteristics of tonsilloliths. In addition, the causes in cases of disagreement between the two modalities were analyzed. RESULTS: The detection rate of tonsilloliths was 46.1% using CT scans, unlike previous reports. The characteristics of tonsillolith were dot-like figures with about 300-500 Hounsfield units within the palatine tonsil under the soft palate. The most common length of tonsilloliths was about 3 or 4 mm. As the subjects aged, the detection rate increased gradually. A significant difference in the tonsillolith detection rate was found between the over and under 40-year-old groups (p < 0.0001). However, the detection rate of tonsilloliths was only 7.3% on panoramic radiographs. A significant correlation was observed between the detection rate of tonsilloliths on panoramic radiographs and CT number (Spearman r = 0.429), size, (Spearman r = 0.318), and number of tonsilloliths (Spearman r = 0.333). CONCLUSION: The present results suggest that tonsilloliths are relatively more common than previously suggested. However, panoramic radiographs detect only a small percentage of palatine tonsilloliths. The low detection rates on panoramic radiographs might be related to the degree of calcification, size, and number of tonsilloliths.

Neutral endopeptidase regulates neurogenic inflammatory responses induced by stimulation of human oral keratinocytes with bacterial lipopolysaccharide and nicotine.

Neutral endopeptidase (NEP) is present on various epithelial cells and inactivates numerous physiologically active peptides. Neutral endopeptidase may regulate proinflammatory signals in oral mucosal epithelium. However, the function of NEP in oral mucosal epithelium is unknown. The present study investigated the action of NEP upon proinflammatory signals on human oral keratinocytes and the influence of endothelin-converting enzyme (ECE)-1, an enzyme similar to NEP, on the functions of NEP. Oral keratinocytes were cultured in medium containing inflammatory inducers [lipopolysaccharide (LPS) and nicotine], NEP inhibitors, and ECE-1/NEP inhibitors, either alone or in combination. The concentrations of substance P (SP) and interleukin-1ß (IL-1ß) were measured in the supernatant. Additionally, the concentrations of SP and IL-1ß were measured in the supernatant of cells incubated with LPS or nicotine after transfection with NEP small interfering RNA (siRNA). The concentrations of SP and IL-1ß were significantly increased in cells incubated with NEP inhibitors and, to a lesser extent, in cells incubated with ECE-1/NEP inhibitors, compared with controls (cells incubated with LPS or nicotine alone). The concentrations of SP and IL-1ß in cells transfected with NEP siRNA were significantly augmented compared with controls. In conclusion, the present study demonstrated that NEP down-regulated the levels of SP and IL-1ß produced from human oral keratinocytes, although ECE-1 may be partly related to the down-regulation.

Association between tooth loss and orodigestive cancer mortality in an 80-year-old community-dwelling Japanese population: a 12-year prospective study.

BACKGROUND: A growing body of evidence has indicated a possible association between oral and gastrointestinal (orodigestive) cancers and periodontal disease or tooth loss. However, the evidence remains contradictory. This study investigated whether tooth loss, which is indicative of poor oral health and a potential source of oral infections, is associated with death from orodigestive cancer. METHODS: The study included 656 subjects in Fukuoka prefecture, Japan, who were 80 years old at baseline in 1998. All subjects underwent oral clinical examination and answered a questionnaire to determine their background characteristics. Cause of death over the 12-year follow-up was recorded from the registers at the Public Health Centers and classified according to the WHO International Classification of Diseases. Statistical analysis of associations was performed using Kaplan-Meier and Cox multivariate regression analyses. RESULTS: A significant association was observed between tooth loss (continuous variable) and cancer death (hazard ratio (HR): 1.03, 95% confidence interval (CI): 1.00-1.07), after adjustment for potential confounders, including sex and smoking status. However, that association became insignificant in the fully adjusted model. On the other hand, tooth loss was significantly associated with orodigestive cancer (HR: 1.06, 95% CI: 1.01-1.13), even in the fully adjusted model including place of residence as a part of socioeconomic status. CONCLUSIONS: This study provides the first evidence in a prospective study in a Japanese population that tooth loss is associated with increased orodigestive cancer mortality, although the causality remains unclear.

High-level activities of daily living and disease-specific mortality during a 12-year follow-up of an octogenarian population.

BACKGROUND: Little is known about the relationship between disease-specific mortality and high-level activities of daily living in the elderly. We examined whether mortality is associated with high-level activities of daily living in an octogenarian population. METHODS: We conducted a population-based cross-sectional and prospective cohort study in 693 older persons aged 80 years and living in Japan's Fukuoka Prefecture. We then evaluated the association between 12-year disease-specific mortality and high-level functional capacity as measured by the Tokyo Metropolitan Institute of Gerontology Index of Competence, which is a standardized multidimensional 13-item instrument; items 1 through 5 are classified as instrumental self-maintenance activity, items 6 through 9 as intellectual activity, items 10 through 13 as social roles activity, and all 13 items together yield total functional capacity. RESULTS: By the 12-year follow-up of the 693 participants, 413 had died, 242 survived, and 38 were unable to be located. Of the 413 who died, 105 died of cardiovascular disease, 73 of respiratory tract disease, 71 of cancer, and 39 of senility. Of the other 125 deaths, 59 were due to other diseases, and the cause of death for 66 participants is not known. The hazard ratio (HR) for all-cause mortality, adjusted for confounding factors with multivariate Cox analyses, fell by 6% (HR 0.937, 95% confidence interval [CI] 0.899-0.978, P = 0.003) with each one-point increase in participants' scores on the Tokyo Metropolitan Institute of Gerontology Index of total functional capacity. With one-point increases in instrumental self-maintenance activity and in intellectual activity, the HRs for all-cause mortality decreased by 14% (HR 0.856, 95% CI 0.787-0.930, P = 0.000) and 12% (HR 0.884, 95% CI 0.794-0.983, P = 0.023), respectively. Respiratory mortality with HR adjustment fell by 11% (HR 0.887, 95% CI 0.804-0.978, P = 0.016) and 24% (HR 0.760, 95% CI 0.627-0.922, P = 0.005) with one-point increases in the scores of total functional capacity and instrumental self-maintenance activity, respectively. Similarly, mortality due to senility fell by 16% (HR 0.838, 95% CI 0.743-0.946, P = 0.004), 29% (HR 0.707, 95% CI 0.564-0.886, P = 0.003), and 29% (HR 0.710, 95% CI 0.522-0.966, P = 0.029) with one-point increases in the scores of total functional capacity, instrumental self-maintenance activity, and intellectual activity, respectively. CONCLUSION: These findings suggest that high-level activities of daily living may be an independent predictor of mortality due to all causes, respiratory disease and senility in older persons.

Monitoring the prevalence of viable and dead cariogenic bacteria in oral specimens and in vitro biofilms by qPCR combined with propidium monoazide.

BACKGROUND: Streptococcus mutans and Streptococcus sobrinus are associated with the development of dental caries in humans. However, previous diagnostic systems are unsuitable for monitoring viable cell numbers in oral specimens. Assessing the relationship between the numbers of viable and dead bacterial cells and oral status is important for understanding oral infectious diseases. Propidium monoazide (PMA) has been reported to penetrate dead cells following membrane damage and to cross-link DNA, thereby inhibiting DNA amplification. In the present study, we established an assay for selective analysis of two viable human cariogenic pathogens, S. mutans and S. sobrinus, using PMA combined with real-time PCR (PMA-qPCR). RESULTS: We designed species-specific primer sets for S. mutans and S. sobrinus, generated standard curves for measuring cell numbers, and evaluated the dynamic range of the assay. To determine the effectiveness of the assay, PMA was added to viable and autoclave-killed cell mixtures. PMA treatment effectively prevented DNA amplification from dead cells. No amplification of DNA from dead cells was observed in these organisms. In addition, we applied this assay to analyze viable cell numbers in oral specimens. A significant correlation was found between the number of viable S. mutans cells in saliva and that in plaque among caries-free patients, whereas no correlation was observed between saliva and carious dentin. The total and viable cell numbers in caries-positive saliva were significantly higher than those in caries-free saliva. Finally, we analyzed the usefulness of this assay for in vitro oral biofilm analysis. We applied PMA-qPCR for monitoring viable S. mutans cell numbers in vitro in planktonic cells and oral biofilm treated with hydrogen peroxide (H2O2). In planktonic cells, the number of viable cells decreased significantly with increasing H2O2 concentration, whereas only a small decrease was observed in biofilm cell numbers. CONCLUSIONS: PMA-qPCR is potentially useful for quantifying viable cariogenic pathogens in oral specimens and is applicable to oral biofilm experiments. This assay will help to elucidate the relationship between the number of viable cells in oral specimens and the oral status.

Activities of daily living dependency and disease-specific mortality during 12-year follow-up in an 80-year-old population.

BACKGROUND AND AIMS: Although total mortality is likely to be higher in elderly individuals with frailty or impaired activities of daily living (ADL), little is known about the relationships between disease-specific mortality and ADL dependency in the elderly. Therefore, we examined whether 12-year disease-specific mortality may be associated with ADL dependency in an 80-year-old population. METHODS: In 1998, of 1,282 community-dwelling residents of Japan's Fukuoka Prefecture, 824 (64.3 %) (309 males and 515 females) participated, the remaining 458 subjects did not participate, and their deaths and causes of death were followed up for 12 years after the baseline examination. ADL dependency was determined according to the guidelines for disabled elderly from the Health, Labor, and Welfare Ministry of Japan, and ADL dependency was measured only at baseline. RESULTS: During the 12-year follow-up, 506 died, 276 did not die, and 42 were lost. Of the 506 who died, 128 died due to cardiovascular disease, 96 to respiratory tract disease, 87 to cancer, and 51 to senility. The subjects were classified into three groups as follows: ADL-1 (independent group, n = 600), ADL-2 (almost-independent group, n = 113), and ADL-3 (dependent group, n = 93).Total-cause mortality was 2.8 times higher in ADL-3 subjects, respiratory disease mortality was 4.1 times higher in ADL-3 subjects, and senility mortality was 5.7 times higher in ADL-3 subjects than in ADL-1 subjects, after adjusting for various confounding factors. There was no association between mortality due to cancer or cardiovascular disease and ADL dependency. CONCLUSIONS: We found an independent association between ADL dependency and mortality due to all causes, respiratory disease or senility, but no association with mortality due to cancer or cardiovascular disease. These findings suggest that improving ADL dependency may reduce all mortality and mortality due to respiratory disease or senility.

Body mass index and disease-specific mortality in an 80-year-old population at the 12-year follow-up.

Although many investigations examined the relationship between body mass index (BMI) and mortality, little is known about the possible associations between BMI and disease-specific mortality in very elderly people. Here we evaluated this association in an 80-year-old population. In 1998, 675 residents in Japan's Fukuoka Prefecture participated. They were followed up for 12 years after the baseline examination; 37 subjects (5.5%) were lost to follow-up. The subjects were divided into six groups by their BMI values: <19.5 (most-thin), 19.5 to <21.1 (relatively thin), 21.1 to <22.5 (thin/normal), 22.5 to <23.8 (normal/overweight), 23.8 to <26.0 (relatively obese), ≥26.0 (most-obese). The most-thin group had the highest mortality from all-causes, and from respiratory disease. The normal/overweight group had the lowest overall mortality among the six BMI groups. These associations were found in the men, but not in the women. The most-obese group did not have higher mortality from all-causes or cardiovascular disease compared to the normal/overweight group. Respiratory disease-related mortality was lowest in the most-obese group. No association was found between BMI group and mortality from cancer. In conclusion, in an 80-year-old Japanese population, mortality from all-causes or respiratory disease was highest in the most-lean group (BMI <19.5), and mortality from all-causes or cardiovascular disease was lowest in the group with BMI 22.5 to <23.8.

Oral health in patients on haemodialysis for diabetic nephropathy and chronic glomerulonephritis.

OBJECTIVE: The objective of this study was to clarify differences in oral health status between patients who needed haemodialysis (HD) owing to diabetic nephropathy (DN) and chronic glomerulonephritis (CGN). MATERIALS AND METHODS: Ninety-eight HD patients who were 50-70 years old were selected as the study subjects [DN group (29 subjects) and CGN group (69 subjects)] to compare with 106 control subjects (control group) not undergoing HD. All HD subjects underwent oral- and systemic-related examination just before HD therapy. RESULTS: The mean number of teeth present in the DN group was significantly less than in the CGN and control groups. The mean percentage of sites with bleeding on probing in the DN group was greater than in the CGN and control groups. The mean salivary flow rate in the DN and CGN groups was significantly lower compared with the control group. CONCLUSION: The patients undergoing HD for DN were found to have fewer teeth and worse periodontal health compared with those undergoing HD for CGN and with the control subjects not undergoing HD. Furthermore, the dental and periodontal health of the patients undergoing HD for CGN was comparable to that of the controls. CLINICAL RELEVANCE: For effective measures of prevention and improvement of oral health in HD patients, clinicians should be aware of the differences in the characteristics of the oral health between patients undergoing HD for DN and CGN.