Association Between the Swallowing Reflex and the Incidence of Aspiration Pneumonia in Patients With Dysphagia Admitted to Long-term Care Wards: A Prospective Cohort Study of 60 Days.

OBJECTIVE: To investigate the association between the Simple Swallowing Provocation Test (SSPT) and the incidence of aspiration pneumonia in patients with dysphagia in long-term care (LTC) wards. DESIGN: The study design was a prospective cohort study. Participants were followed for 60 days from admission. SETTING: LTC wards. PARTICIPANTS: Study participants were patients with dysphagia aged ≥65 years who were admitted to LTC wards between August 2018 and August 2019. In total, 39 participants were included in the analysis (N=39; 20 male, 19 female; mean age, 83.8±8.5y). Participants were divided into 2 groups based on SSPT results: normal swallowing reflex (SSPT normal group) and abnormal swallowing reflex (SSPT abnormal group). The covariates were age and sex, primary disease, history of cerebrovascular disease, Glasgow Coma Scale, body mass index, Geriatric Nutritional Risk Index, the Mann Assessment of Swallowing Ability, Food Intake Level Scale, FIM, and Oral Health Assessment Tool. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The outcome was the incidence of aspiration pneumonia during the first 60 days of hospitalization, and the predictive factor was SSPT: 0.4 mL. RESULTS: The incidence of aspiration pneumonia was 33.3% in the SSPT normal group and 76.2% in the SSPT abnormal group. The φ coefficient (a measure of association for 2 binary variables) was 0.43, the risk ratio (the ratio of the probability of an outcome in an exposed group to the probability of an outcome in an unexposed group) was 2.29, and the 95% confidence interval was 1.14-4.58 for the SSPT abnormal group. CONCLUSIONS: Our findings suggest that the SSPT provides a valid index for the development of aspiration pneumonia in older patients with dysphagia admitted to LTC wards.

[Relationship between the swallowing function and jaw-opening muscle strength in elderly cerebrovascular disease patients].

AIM: In this study, we aimed to clarify the relationship between the swallowing function and the jaw-opening force after cerebrovascular disease. METHODS: Elderly patients with a history of cerebrovascular disease with swallowing disability were enrolled in the present study. The swallowing function was evaluated using the Dysphagia Severity Scale (DSS), and the jaw-opening force was measured using Jaw-Opening Sthenometer (TK2014). The correlation between the DSS and jaw-opening force was analyzed using Spearman's correlation coefficient. Patients were also classified into three groups according to the DSS: normal, dysphagia, and aspiration groups. The jaw-opening forces of the three groups were compared using the Kruskal-Wallis test. RESULTS: Fifty-two patients (27 women, average age 78.8±8.2 years) were recruited. A significant negative correlation was found between the patient age and jaw-opening force in all subjects (r=-0.362, p=0.008) as well as in men (r=-0.548, p=0.005). A significant positive correlation was found between the DSS and jaw-opening force in all subjects (r=0.560, p=0.000) and in both men (r=0.636, p=0.001) and women (r=0.587, p=0.001). The jaw-opening force of the aspiration group was significantly lower than that of the normal group in all subjects (p=0.006), as well as in men (p=0.024) and women (p=0.015). CONCLUSIONS: The DSS and jaw-opening force may have a significant positive correlation. Furthermore, it was shown that the jaw-opening force of the aspiration group was significantly lower than that of the normal-swallowing group.

Molecular analysis for bacterial contamination in dental unit water lines.

Bacterial contamination in dental unit waterlines (DUWLs) was evaluated by molecular techniques in addition to the conventional culture method. Water samples (n=8) from DUWLs were investigated for heterotrophic bacteria by culture method using R2A agar. The selected bacterial antibiotic-resistance genes and Legionella species-specific 16SrDNA were identified by PCR. The profiles of bacterial contamination in DUWLs were further identified by PCR-DGGE. In this study, no antibiotic-resistant or Legionella genes were detected. Polycyclic aromatic hydrocarbon-degrading bacterium, Novosphingobium sp. was the most prevalent in DUWLs. Conventional PCR and PCR-DGGE were shown to be potentially useful for monitoring of bacterial contamination in DUWLs.

A new oral care gel to prevent aspiration during oral care.

AIM: Although oral care is important in the prevention of aspiration pneumonia, the different institutions and practitioners employ various oral care methods, some of which are associated with the risk of aspiration. We have developed a new gel with the physical properties needed for waterless oral care. In the present study, we evaluated and investigated the properties and effectiveness of this gel. METHODS: The physical properties of the trial gel and commercial moisturizing gels were compared using a VAS scale. The effects of plaque elimination were evaluated in healthy volunteers. Brushing was carried out by a dental hygienist using the gel and water. The number of throat suctions performed during brushing was also counted, and the difference was evaluated. RESULTS: In the evaluation of physical characteristics, trial Gel B showed a significantly higher rating than the other gels. In plaque elimination, the rate of decrease in a modified PCR was significantly greater with the gel trial. Suctioning was also performed significantly fewer times with the trial gel. CONCLUSIONS: Good results were obtained with the newly developed trial Gel B with regard to the physical properties and the sensory evaluations. Its effectiveness was also confirmed in plaque elimination and in the evaluated risk of aspiration. The use of Gel B may have the potential to decrease the risk of aspiration during oral care and reduce the occurrence of aspiration pneumonia.

Relationship between mouthful volume and number of chews in young Japanese females.

OBJECTIVE: Modification of eating behavior in Japan is promoted to prevent overweight and obesity, but the effects of such modifications are unclear. This study aimed to clarify the inter- and intra-individual relationship between bite size and number of chews of food. DESIGN AND METHODS: Subjects comprised of 50 young healthy Japanese women (mean age 19.5 years). Food materials were boiled rice and apple. First, the average bite size and the number of chews per mouthful of food were calculated across the study cohort. The number of chews was counted by the subjects themselves and then self-reported. Correlation between the individual one-bite volume and the number of chews per volume was analyzed using Spearman's rank correlation coefficient. Second, the number of chews for three different sized bites of food (half of one bite, one bite, and one-and-a-half bites) were calculated as a prospective observational study. The number of chews for each of the three volumes of food was compared using one way ANOVA with Bonferroni correction. RESULTS: For both food types, there was a negative correlation between individual mouthful volume and number of chews for both food materials. The number of chews per volume decreased as bite sizes increased. CONCLUSION: This study demonstrated an inter- and intra-individual relationship between bite size and the number of chews and suggested that smaller bite sizes were associated with more chews per volume of food.

Factors involved in picky eating in children with disabilities visiting outpatient clinics to receive feeding therapy.

This study aimed to clarify the factors influencing picky eating in children with disabilities based on the hypothesis that primary disease or oral function is involved in picky eating. The subjects were 242 children aged 3-6 years receiving outpatient feeding therapy at our clinic. The subjects' general and oral conditions and picky eating were assessed by their medical recodes. Resultingly, 79 children showed picky eating. Using logistic regression analysis, associated factors of picky eating were primary disease (p = .04), nutritional methods (p = .01), and oral hypersensitivity (p = .04). The relationship with the primary disease suggests the influence of the characteristics of the primary disease. The relationship with oral hypersensitivity may be attributed to avoiding certain sensations. Additionally, the study revealed that the subjects employed tube feeding to compensate for reduced nutritional intake due to picky eating. This study indicated that primary disease and nutritional method as general conditions and oral hypersensitivity as an oral function were possible factors for picky eating. Picky eating was found to occur at varying frequencies depending on the underlying primary disease, especially when the child struggled to tolerate different sensations experienced during meals.

Time-study research on maxillofacial prosthetic treatment.

Unreasonable medical fees can cause problems such as increased medical costs, greater medical disparities, decreased medical standards, and physician shortages. To prevent such problems, it is important to set appropriate medical fees, ensure their proper use, and improve the efficiency of medical care. The treatment of patients with maxillofacial defects is generally more expensive compared with general prosthodontic treatment because it involves more materials and requires more frequently follow-ups for longer period. However, the actual time required for maxillofacial prosthetic treatment is unclear. Therefore, in this study, we aimed to clarify the amount of time spent treating maxillofacial prosthetic patients. We analyzed clinical data from patients undergoing routine maxillofacial prosthetic treatment, irrespective of difficulty level, at 8 university hospitals and 2 dental clinics. We also collected data from maxillofacial prosthodontists on the treatment time required for various Japanese health insurance items, including the fabrication of maxillofacial prostheses. The results revealed that some aspects of maxillofacial prosthetic treatment may take longer to perform and are more costly to perform than previously thought, suggesting the need for some adjustments to the health insurance reimbursement system. Maintaining an appropriate balance between expenditures and fees will greatly benefit patients and physicians, ensuring positive health outcomes and a healthy society.

Oral health status of pregnant women in the Republic of Kiribati.

Prenatal dental examinations were performed from June 2012 to May 2013 in the Republic of Kiribati as a Japan International Cooperation Agency support program. We analyzed the examination data and compared it with Japanese data retrospectively to clarify the oral health condition of pregnant women in the Republic of Kiribati. We recorded the DMF index, gingival status, and calculus attachment, analyzed data of 512 pregnant women. We also compared the city and the rural group data. The average number of present teeth, decayed teeth, missing teeth and filled teeth was 26.9, 2.5, 1.1, 0.2, respectively. Pregnant Kiribati women had significantly more decayed teeth and fewer filled teeth, more severe periodontal condition, more calculus deposition, and more severe gingival swelling than pregnant Japanese women. No significant difference was found in missing and filled teeth, but pregnant women in the city group had significantly more decayed teeth and tooth stumps than those in the rural group. Our findings indicate that pregnant women in Kiribati have more decayed teeth, more missing teeth, fewer filled teeth, and more severe periodontal problems than their counterparts in Japan. Additionally, the oral health status of pregnant women in Kiribati could be subject to regional variations. J. Med. Invest. 70 : 110-114, February, 2023.

The relationship between subjective oral frailty and adverse health outcomes or medical and dental expenditures in the latter-stage older adult: A 6-year longitudinal study.

OBJECTIVES: The study aimed to investigate the relationship between subjective oral frailty and adverse health outcomes or medical and dental expenditures in the latter-stage older adult through a 6-year longitudinal study. METHODS: The participants enrolled in the cross-sectional study were 3564 Tokushima City residents aged 75, 80, 85, and 90 years old who received oral health examinations and who responded to a questionnaire on oral conditions and health behavior at baseline. The data for the occurrence of disability or mortality, and the monthly medical expenditures, dental expenditures, and total medical expenditure of each participant were obtained from the National Health Insurance Database. RESULTS: The total medical expenditure showed significant differences in participants who had difficulties in eating tough foods, difficulties in swallowing tea or soup, and dry mouth when compared to that of healthy participants, in addition to the current medical treatment against the general disease. The 6-year longitudinal study revealed that participants with subjective oral frailty symptoms, including difficulties in eating tough foods and difficulties in swallowing tea or soup at baseline, had significantly higher medical, dental, and total expenditures among 538 participants without certified nursing care. In addition, those with subjective oral frailty or with less than 19 teeth present were shown to have a higher possibility for the occurrence of disability or mortality by the cox proportional hazard analysis. Furthermore, it was found that medical and total expenditures in older adults with adverse health outcomes were higher than that of healthy participants. CONCLUSION: These results suggest that subjective oral frailty in the latter-stage older adult is related to subsequent adverse health outcomes and an increase in medical and dental expenditures.

Brain activation during oral exercises used for dysphagia rehabilitation in healthy human subjects: a functional magnetic resonance imaging study.

Oral exercises, including tongue, lip, and jaw movements, are commonly used in clinical practice as training to improve oral and pharyngeal swallowing in dysphagia patients. These rehabilitation exercises are believed to affect the peripheral and central nervous system at various levels. However, few studies have examined healthy subjects' brain activity while performing oral exercises used in dysphagia rehabilitation. The current study sought to measure brain activation during oral exercises in healthy subjects using functional magnetic resonance imaging (fMRI). Lip-pursing and lip-stretching, tongue protrusion, lateral tongue movement, and oral ball-rolling were selected as tongue and lip exercise tasks. The tasks were performed by eight healthy subjects, and the fMRI data were submitted to conjunction analyses. The results confirmed that head movements during all tasks exhibited translation of <1.0 mm and rotation of <1.0° in x, y, and z coordinates. We found several clear regions of increased brain activity during all four oral exercises. Commonly activated regions during tongue and lip exercises included the precentral gyrus and cerebellum. Brain activation during ball-rolling was more extensive and stronger compared to the other three oral exercises.

Use of ATP Bioluminescence Assay to Evaluate Oral Streptococci.

The statistical correlation between the number of oral streptococci and the results of ATP bioluminescence assay was examined and compared with the results from Streptococcus plate counts and an oral bacteria quantification system. Because a significant correlation was found between ATP (RLU) and the number of bacteria in the oral bacteria quantification system for all seven types of oral streptococci examined, ATP would reflect a conditions of oral hygiene. However, using this assay, it was observed it may be difficult to correctly evaluate bacteria that form aggregates. Furthermore, even a small number of bacteria (below 105 CFU/mL) , which cannot be measured by the oral bacteria quantification system, could be estimated by using ATP bioluminescence assay. It was suggested that this assay could be used for quantitative evaluation of the effect of oral cleaning.

Detection of poststroke oropharyngeal dysphagia with swallowing screening by ultrasonography.

There are currently no standard evaluation tools for poststroke neurogenic oropharyngeal dysphagia. We previously suggested calculating the relative movements of the hyoid bone and larynx by ultrasonography to evaluate swallowing movement. Swallowing movement is altered in neurogenic oropharyngeal dysphagia. Therefore, the present study aimed to verify whether an ultrasonographic evaluation of swallowing movement facilitates the detection of neurogenic oropharyngeal dysphagia. Eighteen healthy male elderly participants (the healthy group) and 18 male stroke patients diagnosed with neurogenic oropharyngeal dysphagia (the dysphagia group) were enrolled. Participants swallowed 5 mL of liquid and water with an adjusted viscosity and the movements of the hyoid bone and larynx were visualized by ultrasonography. The results obtained revealed significant differences in laryngeal duration (static phase), laryngeal displacement (elevation phase), and the hyoid bone-laryngeal motion ratio (HL motion ratio) between the two groups. A multiple regression analysis was performed to adjust for confounding factors, and laryngeal duration (static phase) and the HL motion ratios were identified as factors affecting dysphagia. In the receiver operation characteristic curve of the two variations, the area under the curve for laryngeal duration (static phase) was 0.744 and the cut-off was 0.26 sec with 72.2% sensitivity and 88.9% specificity; the area under the curve for the HL motion ratio was 0.951 and the cut-off was 0.56 with 88.9% sensitivity and 88.9% specificity. Therefore, the objective evaluation of hyoid bone and larynx movements during swallowing by ultrasonography facilitated the detection of neurogenic oropharyngeal dysphagia.

Evaluation of swallowing movement using ultrasonography.

The aim of this study is to develop an index to assess swallowing function by ultrasonography to evaluate the relationship between movements of the hyoid bone and the larynx while swallowing water. Forty-two younger participants (mean age, 20.3 ± 3.4 years) and 42 older participants (mean age, 75.1 ± 10.6 years) with normal swallowing function were included in the study. Movements of the hyoid bone and the larynx while swallowing 5 mL of water were observed using ultrasonography. Two-dimensional distances from the starting points of the hyoid bone and the larynx to their points of maximum movement were measured as displacements. The hyoid bone-laryngeal motion ratio was defined as the hyoid bone displacement divided by the laryngeal displacement. Parameters were compared among four groups: younger male, younger female, older male, and older female. The hyoid bone displacement differed significantly between the younger and older groups, and the laryngeal displacement differed significantly between age groups and sexes. The hyoid bone-laryngeal motion ratio was not significantly correlated with age, height, or body weight, and did not show a significant difference between the four groups. Thus, the hyoid bone-laryngeal motion ratio is an index that evaluates swallowing movement and is independent of physique and physiological changes associated with aging.

Predictive factors associated with poor outcomes for older adult inpatients in the convalescent rehabilitation ward.

This study aimed to determine predictive factors associated with poor outcomes among older adult inpatients in the convalescent rehabilitation ward. We also examined the validity of factors that were identified as predictive of poor outcomes. Study subjects were 104 older adult inpatients in the convalescent rehabilitation ward, divided into two groups based on outcome at discharge. Group I included the outcomes of death or transfer to an acute care hospital and Group II included all other outcomes. Data were retrospectively collected from older adults' medical records, including: activities of daily living, swallowing grade, nutritional index, and blood biochemistry data. Logistic regression analysis was used to extract predictive factors associated with poor outcomes. Next, we calculated the Stratum-specific likelihood ratio (SSLR) for each extracted factor. Two items were extracted as predictive factors with AUCs ≥ 0.7 : N-terminal pro-brain natriuretic peptide (NT-proBNP) and days from onset to hospitalization. The SSLRs showed the risk for a poor outcome increased when NT-proBNP was ≥ 2500 pg / ml, and when there were ≥ 35 days from onset to hospitalization. Our findings suggest these predictive factors provide a valid index to predict poor outcomes among older adults from the early stage of admission. J. Med. Invest. 67 : 304-310, August, 2020.

Influence of food volume per mouthful on chewing and bolus properties.

BACKGROUND: Behaviors relating to food intake, i.e., speed of chewing, number of chews, and bite size, are important for decreasing energy intake, which might reduce excess body weight and thus metabolic risk. This study aimed at investigating the influence of mouthful volume on the number of chews and food bolus properties in addition to clarifying appropriate eating behaviors related to mouthful volume. METHODS: Fifteen young Japanese women volunteered to participate. The subjects were asked to spit the food bolus in a glass dish just before swallowing when eating 3 different foods: boiled rice, fish sausage, and peanuts. The 3 physical properties of solidity, adhesiveness, and cohesiveness were measured in the bolus, and the number of chews was noted. RESULTS: The number of chews significantly increased with increasing mouthful volume with all 3 foods; conversely, the number of chews per unit of food weight (g) decreased significantly with boiled rice and fish sausage. Trends were observed for solidity and cohesiveness, which varied with increasing mouthful volumes. CONCLUSIONS: Decreased mouthful volume resulted in a greater number of chews per weight of food and more appropriate bolus properties; therefore, a change in mouthful volume could be a useful behavior modification for regulation of energy intake.

Microfloral characterization of the tongue coating and associated risk for pneumonia-related health problems in institutionalized older adults.

OBJECTIVES: To characterize a comprehensive outline of the oral microflora related to pneumonia in older adults. DESIGN: Prospective and retrospective longitudinal study. SETTING: Community. PARTICIPANTS: Long-term hospitalized patients and people in nursing homes (343 subjects, aged > or =65). MEASUREMENTS: Subjects were assessed at baseline for pneumonia-related health problems. The flora of the tongue coating was characterized according to terminal restriction fragment length polymorphism (T-RFLP) analysis. All subjects were followed prospectively for 6 months for a diagnosis of pneumonia. The number of febrile days (>37.5 degrees C) was assessed in 299 subjects who were observed for 12 months (retrospectively for 6 months and prospectively for 6 months). The follow-up data were analyzed using multivariate regression analyses in relation to the baseline data, including T-RFLP patterns. RESULTS: T-RFLP patterns outlining the floral composition of the tongue coating were grouped into Clusters A, B, C, and D. According to Cox regression analysis, the subjects in Clusters C (hazard ratio (HR)=4.0, 95% confidence interval (CI)=1.1-15.1) and D (HR=4.9, 95% CI=1.2-21.1) were at a significantly greater risk of pneumonia than those in Cluster A, independent of other confounding factors. Logistic regression analysis adjusting for the same covariates indicated that the number of subjects with more than 9 febrile days per year was significantly lower in Cluster A than in the other clusters. CONCLUSION: The comprehensive microfloral profile of the tongue coating is closely related to pneumonia-related health problems in institutionalized older adults.

Subjective assessment of chewing function of obturator prosthesis wearers.

PURPOSE: Assessments of masticatory performance and occlusal force for wearers of obturator prostheses were performed as clinical objective assessments and reported in an earlier study. The purpose of the present study was to evaluate clinically the chewing function of obturator prosthesis wearers by self-evaluations and to examine their relationship to the objective assessments. MATERIALS AND METHODS: Twenty patients with maxillofacial obturator prostheses who were having a periodic checkup at the maxillofacial rehabilitation clinic in Kyushu University Hospital were recruited for this study. Chewing function was evaluated by 3 assessment tools: a self-assessment mastication scale, a chewing function score, and a mastication score. In addition, correlations among these assessments and objective tests--ie, masticatory performance and maximum occlusal force--were analyzed by the Spearman rank correlation coefficient. RESULTS: The mean self-assessment mastication scale was 63.2 (SD 31.8), the chewing function score was 54.0 (SD 30.2), and the mastication score was 51.4 (SD 33.3). There was no statistically significant relationship between the self-assessment mastication scale and each objective test. However, there were significant correlations between each semisubjective score--the chewing function score and the mastication score--and masticatory performance. There was no relationship between each semisubjective score and maximum occlusal force. CONCLUSION: A self-assessment mastication scale was not always in agreement with objective assessments, and assessments made by patients should be taken into consideration when arranging maxillofacial rehabilitation. Conversely, both chewing function and mastication scores corresponded with masticatory performance, and these would be useful as screening tests before performing objective tests.

Clinical assessment of chewing function of obturator prosthesis wearers by objective measurement of masticatory performance and maximum occlusal force.

PURPOSE: Eating, which includes chewing and swallowing, is an oral function that influences quality of life. Though the swallowing ability of maxillectomy patients was reported in our previous study, the chewing function has not been fully reported to date. Thus, the purpose of this study was to evaluate the chewing function of obturator prosthesis wearers by measurement of masticatory performance and occlusal force. The relationship of these 2 measurements was also investigated. MATERIALS AND METHODS: Twenty maxillofacial obturator prosthesis wearers undergoing periodic checkup at the maxillofacial rehabilitation clinic in Kyushu University Hospital were recruited for this study. Additionally, 20 young, healthy individuals were recruited as controls. Data on masticatory performance, which was measured by a sieve method using hydrocolloid material, and maximum occlusal force, which was measured by the Dental Prescale System (Fuji Film), were obtained for each participant. RESULTS: The mean of masticatory performance was 2.6 (SD 1.2) on a 1.40-mm mesh. There was no significant difference in masticatory performance between the patient group and the controls. The mean maximum occlusal force of the patient group was 625.9 N (SD 299.1 N), which was significantly lower than that of the control group. There was no significant correlation between masticatory performance and maximum occlusal force for the patient group in this study (P = .3726). CONCLUSION: Masticatory performance of obturator prosthesis wearers with dentate or partially edentulous maxillae was not different from that of young, healthy individuals, though maximum occlusal force of these patients was lower than that of controls.

Objective clinical assessment of change in swallowing ability of maxillectomy patients when wearing obturator prostheses.

PURPOSE: Evaluation of treatment outcome is important in maxillofacial rehabilitation. Although eating is one of the oral functions that most strongly influences patients' quality of life, only a few reports exist on the objective assessment of swallowing for maxillectomy patients. The purpose of this study was to identify changes in the swallowing ability of maxillectomy patients when wearing obturator prostheses through the use of an objective clinical assessment. MATERIALS AND METHODS: The swallowing ability of 38 postmaxillectomy patients consecutively treated with obturator prostheses was objectively evaluated with the "water-drinking test" that was developed for the assessment of dysphagia patients after cerebrovascular disease. In this test, the subjects were instructed to drink 30 mL of water in one swallow. The profile was evaluated with the combination of the time required for drinking the water and the incidence of cough reflex. Statistical analysis was performed using the Wilcoxon signed-rank test, the paired t test, and the Chi-square test with StatView 5.0 for the Macintosh. RESULTS: Performance improved significantly when the patients wore prostheses (P = .0026, Wilcoxon signed-rank test). The mean drinking times without and with prostheses were 8.2 +/- 6.3 s and 5.0 +/- 3.5 s, respectively. Drinking time was shortened significantly when the prosthesis was worn (P = .0002, paired t test). The assessment of behavior and episodes revealed that the swallowing ability of the maxillectomy patients was significantly improved when a prosthesis was worn (P = .0002, Chi-square test). CONCLUSION: The swallowing ability of maxillectomy patients was quantitatively and qualitatively improved with obturator prostheses.