Sumio Akifusa

Oral Health and Mortality Risk from Pneumonia in the Elderly

Although poor oral health influences the occurrence of pulmonary infection in elderly people, it is unclear how the degree of oral health is linked to mortality from pulmonary infection. Therefore, we evaluated the relationship between oral health and four-year mortality from pneumonia in an elderly Japanese population. The study population consisted of 697 (277 males, 420 females) of the 1282 individuals who were 80 years old in 1997. Data on oral and systemic health were obtained by means of questionnaires, physical examinations, and laboratory blood tests. One hundred eight of the study persons died between 1998 and 2002. Of these, 22 deaths were due to pneumonia. The adjusted mortality due to pneumonia was 3.9 times higher in persons with 10 or more teeth with a probing depth exceeding 4 mm (periodontal pocket) than in those without periodontal pockets. Therefore, the increase in teeth with periodontal pockets in the elderly may be associated with increased mortality from pneumonia.

Interrelationship of oral health status, swallowing function, nutritional status, and cognitive ability with activities of daily living in Japanese elderly people receiving home care services due to physical disabilities.

OBJECTIVESnMalnutrition and cognitive impairment lead to declines in activities of daily living (ADL). Nutritional status and cognitive ability have been shown to correlate with oral health status and swallowing function. However, the complex relationship among the factors that affect decline in ADL is not understood. We examined direct and indirect relationships among oral health status, swallowing function, nutritional status, cognitive ability, and ADL in Japanese elderly people living at home and receiving home care services because of physical disabilities.nnnMETHODSnParticipants were 286 subjects aged 60 years and older (mean age, 84.5±7.9 years) living at home and receiving home care services. Oral health status (the number of teeth and wearing dentures) was assessed, and swallowing function was examined using cervical auscultation. Additionally, ADL, cognitive ability, and nutritional status were assessed using the Barthel Index, the Clinical Dementia Rating Scale, and the Mini Nutritional Assessment-Short Form, respectively. Path analysis was used to test pathways from these factors to ADL.nnnRESULTSnThe mean number of teeth present in the participants was 8.6±9.9 (edentates, 40.6%). Dysphagia, malnutrition, and severe cognitive impairment were found in 31.1%, 14.0%, and 21.3% of the participants, respectively. Path analysis indicated that poor oral health status and cognitive impairment had a direct effect on denture wearing, and the consequent dysphagia, in addition to cognitive impairment, was positively associated with malnutrition. Malnutrition as well as dysphagia and cognitive impairment directly limited ADL.nnnCONCLUSIONSnA lower number of teeth are positively related to swallowing dysfunction, whereas denture wearing contributes to recovery of swallowing function. Dysphagia, cognitive impairment, and malnutrition directly and indirectly decreased ADL in elderly people living at home and receiving home nursing care. The findings suggest that preventing tooth loss and encouraging denture wearing when teeth are lost may indirectly contribute to maintaining or improving ADL, mediated by recovery of swallowing function and nutritional status.

Relationship between nutrition status and dental occlusion in community‐dwelling frail elderly people

Aim:u2003 This study aimed to determine the risk of malnutrition in some communities where the frail elderly receive public long‐term care insurance. We also clarified the dental problems in those at risk of malnutrition.

Relationship between Tooth Loss and Electrocardiographic Abnormalities in Octogenarians

Recent reports have suggested that periodontal disease is a risk factor for coronary heart disease (CHD). However, little is known about the relationship between periodontal disease and CHD in the very elderly. Therefore, we evaluated the association between tooth loss and abnormal ECG findings in octogenarians. Of the 1282 octogenarians in Fukuoka Prefecture, Japan, 697 participated. Oral examinations-including a tooth count and an assessment of the Community Periodontal Index-and a 12-lead ECG were performed. Logistic regression analysis revealed that individuals with < 20 teeth had increased prevalence of ST segment depression, and T-wave abnormalities, after we adjusted for gender, smoking, serum cholesterol and glucose, blood pressure, and body mass index. Compared with individuals with ≥ 20 teeth, edentulous individuals had an increased prevalence of T-wave abnormalities and arrhythmias after adjustment for coronary risk factors. We conclude that tooth loss may be an independent predictor of abnormal ECG findings in octogenarians.

Bacterial diversity in saliva and oral health-related conditions: the Hisayama Study

This population-based study determined the salivary microbiota composition of 2,343 adult residents of Hisayama town, Japan, using 16S rRNA gene next-generation high-throughput sequencing. Of 550 identified species-level operational taxonomic units (OTUs), 72 were common, in ≥75% of all individuals, as well as in ≥75% of the individuals in the lowest quintile of phylogenetic diversity (PD). These “core” OTUs constituted 90.9u2009±u20096.1% of each microbiome. The relative abundance profiles of 22 of the core OTUs with mean relative abundances ≥1% were stratified into community type I and community type II by partitioning around medoids clustering. Multiple regression analysis revealed that a lower PD was associated with better conditions for oral health, including a lower plaque index, absence of decayed teeth, less gingival bleeding, shallower periodontal pockets and not smoking, and was also associated with tooth loss. By contrast, multiple Poisson regression analysis demonstrated that community type II, as characterized by a higher ratio of the nine dominant core OTUs, including Neisseria flavescens, was implicated in younger age, lower body mass index, fewer teeth with caries experience, and not smoking. Our large-scale data analyses reveal variation in the salivary microbiome among Japanese adults and oral health-related conditions associated with the salivary microbiome.

Relationship between chewing ability and high‐level functional capacity in an 80‐year‐old population in Japan

OBJECTIVESnTo evaluate the association between high-level functional capacity and chewing in a middle-old community-based population.nnnBACKGROUNDnAlthough basic and instrumental activities of daily living are known to be associated with chewing ability in the elderly, an association between higher levels of competence and chewing ability has not been evaluated in the elderly.nnnMATERIALS AND METHODSnThe association between chewing ability using a number of different foods and high-level functional capacity by the Tokyo Metropolitan Institute of Gerontology was evaluated in 694, 80-year-old people residing in Fukuoka Prefecture, Japan.nnnRESULTSnA significant correlation was found, using multiple regression or logistic regression analyses adjusted for various confounding factors, between the number of total chewable foods, hard foods or moderately hard foods, and total functional capacity, instrumental activity, intellectual activity or social role ability. In contrast, the number of slightly hard foods, easily chewable foods and remaining teeth were only partly related to total functional capacity and intellectual activity.nnnCONCLUSIONnHigh-level functional capacity including intellectual activity and social role in middle-old elderly was associated with the ability to chew hard foods than to chew easily chewable foods. Maintenance of chewing ability in elderly might result in better intellectual activity and social role.

Relationship Between Obesity and Physical Fitness and Periodontitis

BACKGROUNDnObesity and exercise are important elements associated with lifestyle-related diseases, and studies suggested that these factors may also be related to periodontitis. This study investigates the relationship between obesity and physical fitness and periodontitis.nnnMETHODSnOne thousand, one hundred and sixty Japanese subjects, aged 20 to 77 years, who participated in health examinations at Fukuoka Health Promotion Center were analyzed. Periodontal conditions were evaluated using the Community Periodontal Index (CPI), and subjects with > or =3 sextants of CPI code 3 or 4 were defined as having severe periodontitis. We used the body mass index (BMI) and percentage of body fat as indicators of obesity and estimated the maximal oxygen consumption (VO(2max)) during exercise as an indicator of physical fitness. We divided these variables into quintiles. We examined the single effect and interactions of the obesity index and VO(2max) on severe periodontitis.nnnRESULTSnThe lowest quintile in BMI and the highest quintile in VO(2max) were inversely associated with severe periodontitis, singly, in multivariate logistic regression analyses. Subjects with the combined lowest quintile in BMI and the highest quintile in VO(2max) had a significantly lower risk of severe periodontitis compared to subjects with other combined quintiles in BMI and in VO(2max) (odds ratio: 0.17; 95% confidence interval: 0.05 to 0.55).nnnCONCLUSIONnThis study suggests that obesity and physical fitness may have some interactive effect on periodontal health status.

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.

Globular adiponectin-induced RAW 264 apoptosis is regulated by a reactive oxygen species-dependent pathway involving Bcl-2.

Globular adiponectin (gAd), a truncated form of adipocyte-derived cytokine, stimulates RAW 264 cells to produce reactive oxygen species (ROS), which trigger an apoptotic cascade. In this study, we investigated the generation of intracellular and mitochondrial ROS in gAd-stimulated RAW 264 cells. Treatment with gAd efficiently induced the generation of intracellular and mitochondrial ROS, as detected by dichlorodihydrofluorescein diacetate and MitoSOX fluorescence, respectively. Furthermore, gAd treatment significantly increased 8-oxoguanine, a specific indicator of oxidative DNA damage. The transfection of RAW 264 cells with iNOS- and gp91(phox)-specific small interfering RNA reduced markedly the generation of intracellular, but not mitochondrial, ROS. Quantitative PCR revealed that the expression ratio of Bcl-2 to Bax was reduced in a time-dependent manner in gAd-treated RAW 264 cells. The overexpression of Bcl-2 markedly inhibited gAd-induced apoptosis in RAW 264 cells and also reduced both the intracellular and the mitochondrial ROS generation induced by gAd treatment. Moreover, the overexpression of Bcl-2 significantly suppressed gAd-induced NO secretion and NOS activity. In addition, the inhibition of NOS activity partially reduced the oxidative DNA damage induced by gAd. Taken together, these results demonstrate that the gAd-induced apoptotic pathway acting via ROS/RNS generation involves Bcl-2.

Regulation of globular adiponectin-induced apoptosis by reactive oxygen/nitrogen species in RAW264 macrophages

Adiponectin, produced predominantly by differentiating adipocytes, is a protein hormone with antidiabetic and immunosuppressive properties. Here, we report evidence that treatment with globular adiponectin (gAd) induces apoptosis in murine macrophage-like RAW264 cells through the generation of reactive oxygen and/or nitrogen species (ROS/RNS). Treatment with gAd induced apoptosis and enhanced the activities of caspase-3 and -9, but not caspase-8. The gAd stimulation increased ROS generation and significantly reduced the ratio of NADPH to total NADP. Pretreatment with diphenyleneiodonium or apocynin reduced ROS and apoptosis in gAd-treated cells. In addition, transfection with p47(phox)- or gp91(phox)-specific small interfering RNA (siRNA) partially reduced ROS and apoptosis in response to gAd treatment. These results suggest that the administration of gAd induces apoptosis after ROS generation involving activation of NADPH oxidases. The gAd stimulation increased the release of NO into the culture medium, the activity of nitric oxide synthase (NOS), and the expression of inducible NOS (iNOS) mRNA in RAW264 cells. l-NAME reduced gAd-induced apoptotic cell death. In addition, transfection with an iNOS-specific siRNA markedly reduced the generation of NO and the population of apoptotic cells. Taken together, these results demonstrate that the gAd-induced apoptotic process in RAW264 cells involves ROS and RNS, which are generated by NADPH oxidases and iNOS, respectively.