Association between Death or Hospitalization and Observable Variables of Eating and Swallowing Function among Elderly Residents in Long-Term Care Facilities: A Multicenter Prospective Cohort Study.

This 1-year multicenter prospective cohort study aimed to determine the association between observable eating and swallowing function factors and outcomes (death/hospitalization or survival) among elderly persons in long-term care insurance facilities in Japan. Baseline assessments of factors, such as language, drooling, halitosis, hypersalivation, tongue movement, perioral muscle function, coughing, respiration after swallowing, rinsing, and oral residue, among others, were conducted. A score of 0 was considered positive, and a score of 1 or 2 was considered negative. Patient age, sex, body mass index, Barthel index, and Clinical Dementia Rating were recorded. The death/hospitalization or survival rates over 1 year were recorded, and patients were allocated into groups depending on the respective outcome (death/hospitalization group or survival group) and baseline characteristics. A total of 986 residents from 32 facilities were included, with 216 in the death/hospitalization group and 770 in the survival group. Language, salivation, halitosis, perioral muscle, coughing, respiration after swallowing, rinsing, and oral residue were significantly associated with the outcomes (p < 0.05). Therefore, routine performance of these simple assessments by caregivers may allow early detection and treatment to prevent death, pneumonia, aspiration, and malnutrition in elderly persons.

Effects of Head and Neck Alignment and Pharyngeal Anatomy on Epiglottic Inversion During Swallowing in Dysphagic Patients.

The effects of head and neck alignment and pharyngeal anatomy on epiglottic inversion remain unclear. This study investigated the factors involved in epiglottic inversion, including head and neck alignment and pharyngeal anatomy, in patients with dysphagia. Patients with a chief complaint of dysphagia and who underwent videofluoroscopic swallowing study at our hospital from January to July 2022 were enrolled. They were divided into three groups based on the degree of epiglottic inversion as the complete-inversion (CI), partial-inversion (PI), and non-inversion group (NI) groups. Data were compared among the three groups; a total of 113 patients were analyzed. The median age was 72.0 (IQR: 62.0-76.0) years; 41 (36.3%) and 72 (63.7%) were women and men, respectively. There were in 45 (39.8%) patients in the CI, 39 (34.5%) in the PI, and 29 (25.7%) in the NI groups, respectively. Single-variable analysis revealed significant relation to epiglottic inversion of Food Intake LEVEL Scale score, penetration-aspiration score with 3-mL thin liquid bolus, epiglottic vallecula and pyriform sinus residue, hyoid position and displacement during swallowing, pharyngeal inlet angle (PIA), epiglottis to posterior pharyngeal wall distance, and body mass index. Logistic regression analysis with complete epiglottic inversion as the dependent variable revealed the X coordinate at maximum hyoid elevation position during swallowing and PIA as significant explanatory variables. These results suggest that epiglottic inversion is constrained in patients with dysphagia who have poor head and neck alignment or posture and a narrow pharyngeal cavity just before swallowing.

Association of Hyper-Low-Density Lipoprotein and Hypo-High-Density Lipoprotein Cholesterolemia with Low Saliva Flow Rates in Japanese Community-Dwelling Elders

Abstract Introduction The associations of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein (HDL-C) with reduced saliva flow rates have not been previously reported. Objective The present study aimed to assess the association of cholesterolemia with reduced saliva flow rates in community-dwelling elderly subjects. Methods The present study analyzed 342 participants (170 males and 172 females aged between 78 and 79 years old). Unstimulated salivary flow rate (USFR) was assessed using a cotton roll method. Low-USFR was defined as 0.10 g/30 seconds. Stimulated salivary flow rate (SSFR) was assessed by having the participants chew tasteless gum for 3minutes. Low-SSFR was defined as 1.0 mL/minute. Blood samples were collected for the measurement of LDL-C, HDL-C, rheumatoid factor, hemoglobin A1c, and creatinine. To assess depression, the General Health Questionnaire 30 was used. A standardized questionnaire was completed, covering the current and previous medications of the participants and smoking status. We stratified the serum LDL-C levels of the participants as normal, moderate or severe hyper-LDL cholesterolemia and serum HDL-C levels as normal or hypo-HDL cholesterolemia. Multivariate logistic regression models were established and low-USFR or low-SSFR were set as dependent variables in the aforementioned models. Results After controlling for the effects of the other variables, the odds ratios (ORs) (95% confidence intervals [CIs]) for low-USFR were 2.25 (1.10-4.61) for moderate and 5.69 (1.55-20.8) for severe hyper-LDL cholesterolemia, while that of hypo-HDL cholesterolemia was 3.40 (1.33-8.69). Severe hyper-LDL cholesterolemia was also associated with low-SSFR with an OR of 3.89 (1.39-10.88). Conclusion Elderly patients with cholesterolemia have a risk of reduced salivary flow rate.

Association of Hyper-Low-Density Lipoprotein and Hypo-High-Density Lipoprotein Cholesterolemia with Low Saliva Flow Rates in Japanese Community-Dwelling Elders.

Introduction The associations of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein (HDL-C) with reduced saliva flow rates have not been previously reported. Objective The present study aimed to assess the association of cholesterolemia with reduced saliva flow rates in community-dwelling elderly subjects. Methods The present study analyzed 342 participants (170 males and 172 females aged between 78 and 79 years old). Unstimulated salivary flow rate (USFR) was assessed using a cotton roll method. Low-USFR was defined as 0.10 g/30 seconds. Stimulated salivary flow rate (SSFR) was assessed by having the participants chew tasteless gum for 3 minutes. Low-SSFR was defined as 1.0 mL/minute. Blood samples were collected for the measurement of LDL-C, HDL-C, rheumatoid factor, hemoglobin A1c, and creatinine. To assess depression, the General Health Questionnaire 30 was used. A standardized questionnaire was completed, covering the current and previous medications of the participants and smoking status. We stratified the serum LDL-C levels of the participants as normal, moderate or severe hyper-LDL cholesterolemia and serum HDL-C levels as normal or hypo-HDL cholesterolemia. Multivariate logistic regression models were established and low-USFR or low-SSFR were set as dependent variables in the aforementioned models. Results After controlling for the effects of the other variables, the odds ratios (ORs) (95% confidence intervals [CIs]) for low-USFR were 2.25 (1.10-4.61) for moderate and 5.69 (1.55-20.8) for severe hyper-LDL cholesterolemia, while that of hypo-HDL cholesterolemia was 3.40 (1.33-8.69). Severe hyper-LDL cholesterolemia was also associated with low-SSFR with an OR of 3.89 (1.39-10.88). Conclusion Elderly patients with cholesterolemia have a risk of reduced salivary flow rate.

Characteristics of medication-induced xerostomia and effect of treatment.

OBJECTIVE: Side-effects of medications cause xerostomia. There have been cases where a medication has been discontinued owing to its severe side-effects. Therefore, the xerostomia must be treated to ensure that the primary disease is managed effectively. This study analyzed the actual status of patients with medication-induced xerostomia and investigates factors associated with its improvement. METHODS: This study assessed 490 patients diagnosed with medication-induced xerostomia who had an unstimulated salivary flow of ≤0.1 mL/min and received treatment for xerostomia at a xerostomia clinic. Patient age, sex, medical history, medications used, disease duration of xerostomia, and psychological disorders were recorded. The anticholinergic burden was assessed using the Anticholinergic Cognitive Burden scale. The unstimulated salivary flow was measured by the spitting method. According to their symptoms and diagnoses, the patients were introduced to oral lubricants, instructed on how to perform massage, and prescribed Japanese herbal medicines, and sialogogues. Factors associated with the subjective improvement of xerostomia and objective changes in the salivary flow rate were recorded at six months. RESULTS: Xerostomia improved in 338 patients (75.3%). The improvement rate was significantly lower in patients with psychiatric disorders (63.6%) (P = 0.009). The improvement rate decreased as more anticholinergics were used (P = 0.018). However, xerostomia improved in approximately 60% of patients receiving three or more anticholinergics. The unstimulated salivary flow increased significantly more in patients who reported an improvement of xerostomia (0.033±0.053 mL/min) than in those who reported no improvement (0.013±0.02 mL/min) (P = 0.025). CONCLUSION: Xerostomia treatment improved oral dryness in 75.3% of patients receiving xerogenic medications in this study. If xerostomia due to side-effects of medications can be improved by treatment, it will greatly contribute to the quality of life of patients with xerogenic medications and may reduce the number of patients who discontinue medications.

Evaluating the effect of management on patients with oral hypofunction: A longitudinal study.

INTRODUCTION: Declining oral function may affect subsequent physical frailty in the older population. The aim of this longitudinal study was to summarise data on patients who underwent functional oral examination and evaluate the impact of management on patients with oral hypofunction (OHF). METHODS: Dental outpatients aged over 65 years at their initial visit to the Niigata University Hospital received detailed assessment of seven oral function items to diagnose oral hypofunction using diagnostic criteria defined by the Japanese Society of Gerodontology. Patients with OHF at the first assessment received management including oral health guidance for low function and dental treatment. They were re-evaluated approximately 6 months later and the two assessments were compared. According to the results of the second assessment, the patients were divided into two groups: OHF improved and OHF re-diagnosed. RESULTS: Of the 273 patients who underwent the first assessment, 86 (31.5%) were diagnosed with OHF and received management. Of those, 42 (48.8%) completed the second assessment. Comparing the first and second assessment, significant improvement was observed in oral hygiene, occlusal force, tongue-lip motor function of /pa/, mastication and swallowing. The change in values from the first assessment demonstrated a significant difference between the OHF improved and re-diagnosed groups only in occlusal force. CONCLUSION: Management for patients with OHF can contribute to the improvement of poor oral function, and an increase in occlusal force was notable in the recovery from OHF.

Association between denture use and food form in older adults requiring long-term care: A multicenter cross-sectional study.

PURPOSE: This study aimed to determine whether denture use contributes to maintaining and improving food forms in long-term care facility (LTCFs) residents. METHODS: In 888 residents of 37 LTCFs in Japan, the following were investigated: nutritional intake status, food forms, age, sex, Barthel index (BI), clinical dementia rating (CDR), number of teeth present, number of occlusal supports, swallowing function, and use of dentures. Among all residents, those who were well-nourished and had ≤9 occlusal supports were analyzed. Based on standardized criteria, the food forms consumed by the subjects were divided into two groups: dysphagia and normal diet, which were further classified into four levels. Analysis was performed using a generalized estimation equation with the four levels of food forms as dependent variables and age, sex, BI, CDR, presence of dysphagia, number of teeth present, and use of dentures as independent variables. RESULTS: The final analysis included 622 (70.0%) residents. Of these, 380 (61.1%) used dentures. The analyses revealed that food form was significantly associated with age (adjusted odds ratio [OR], 0.98), BI (OR, 1.04), number of teeth present (OR, 1.03), presence of dysphagia (OR, 0.44), and use of dentures (OR, 2.82). CONCLUSIONS: Denture use was associated with food forms among Japanese LTCF residents. This indicates that the use of dentures is related to the maintenance of food forms, even in the elderly who participate in few activities of daily living, have reduced cognitive function, and require long-term care.

Observational Variables for Considering a Switch from a Normal to a Dysphagia Diet among Older Adults Requiring Long-Term Care: A One-Year Multicenter Longitudinal Study.

This one-year multicenter longitudinal study aimed to assess whether older adult residents of long-term care facilities should switch from a normal to a dysphagia diet. Using the results of our previous cross-sectional study as baseline, older adults were subdivided into those who maintained a normal diet and those who switched to a dysphagia diet. The explanatory variables were age, sex, body mass index (BMI), Barthel Index, clinical dementia rating (CDR), and 13 simple and 5 objective oral assessments (remaining teeth, functional teeth, oral diadochokinesis, modified water swallowing test, and repetitive saliva swallowing test), which were used in binomial logistic regression analysis. Between-group comparison showed a significantly different BMI, Barthel Index, and CDR. Significant differences were also observed in simple assessments for language, drooling, tongue movement, perioral muscle function, and rinsing and in objective assessments. In multi-level analysis, switching from a normal to a dysphagia diet was significantly associated with simple assessments of tongue movement, perioral muscle function, and rinsing and with the objective assessment of the number of functional teeth. The results suggest that simple assessments can be performed regularly to screen for early signs of discrepancies between food form and eating/swallowing functions, which could lead to the provision of more appropriate food forms.

Factors Associated with Food Form in Long-Term Care Insurance Facilities.

We examined factors related to dietary intake status (food form) of long-term care facility (LTCF) residents to identify factors related to proper food form choice for older individuals requiring nursing care. We surveyed 888 residents from 37 LTCFs in Japan. We evaluated basic information (age, sex, body mass index [BMI]), food form (swallowing-adjusted diet class), Barthel Index (BI), Clinical Dementia Rating (CDR), simply evaluated eating and swallowing functions, the number of present/functional teeth, oral diadochokinesis, repetitive saliva swallowing test (RSST), and modified water swallowing test. To clarify factors associated with food form, participants who had good nutrition by oral intake were categorized into the dysphagic diet (DD) and normal diet (ND) groups. Multi-level analyses were used to detect oral functions associated with food form status. Among objective assessments, BMI (odds ratio [OR] 0.979, 95% confidence interval [CI] - 0.022- to 0.006, p = 0.001), BI (OR 0.993, 95% CI - 0.007 to - 0.004, p < 0.001), CDR 3.0 (OR 1.002, 95% CI 0.002‒0.236, p = 0.046), present teeth (OR 0.993, 95% CI - 0.007 to - 0.001, p = 0.011), functional teeth (OR 0.989, 95% CI - 0.011 to - 0.005, p < 0.001), and RSST (OR 0.960, 95% CI - 0.041 to - 0.007, p = 0.006) were significantly associated with DD vs ND discrimination. Simple evaluations of coughing (OR 1.056, 0.054‒0.198, p = 0.001) and rinsing (OR 1.010, 0.010‒0.174, p = 0.029) could also discriminate food form status. These simple evaluations provide insight into the discrepancies between food form status and eating abilities of LTCF residents. Periodic evaluations by the nursing caregiver may help to prevent aspiration by older individuals with dysphagia.

Impact of oral function on regaining oral intake and adjusting diet forms for acute stroke patients.

BACKGROUND: Outcome prediction for dysphagia recovery is essential for rehabilitation treatment planning. Several studies have reported various predictors for resuming oral feeding after post-stroke dysphagia. However, evidence on oral health and function, a crucial part of feeding, has rarely been reported. Therefore, the goal of this study was to identify the oral status-related factors that could predict oral intake resumption in acute stroke patients. METHODS: 80 acute stroke patients with dysphagia were included. Clinical data, including the changes of general condition, oral and swallowing functions, were collected once a week until discharge. Patients were divided into two groups based on the outcome of the food intake level scale at discharge, and data were compared between the groups. RESULTS: 60 patients had regained complete oral intake before discharge. Multiple logistic regression showed that posterior tongue pressure could significantly predict complete oral intake recovery. Tongue pressure and modified water swallowing test score also significantly influenced diet forms. In addition, Spearman correlation analysis showed that improvement of other oral status-related factors, such as oral moisture and dentition status, also indicated the improvement of diet forms and swallowing function during the hospital stay. CONCLUSION: Tongue pressure measurement could be a useful oral status-related indicator for predicting complete oral intake and adjusting diet forms for acute stroke patients during hospitalization. Acute stroke patients should receive proper oral status evaluation and implementation to enhance functional recovery.

Pneumonia incidence and oral health management by dental hygienists in long-term care facilities: A 1-year prospective multicentre cohort study.

OBJECTIVE: To investigate the association between oral health management (OHM) by dental hygienists and the occurrence of pneumonia, and determine the effectiveness of OHM in pneumonia prevention. BACKGROUND: In long-term care facilities in Japan, the need for professional OHM is increasing with an increase in the number of severely debilitated residents. MATERIALS AND METHODS: A 1-year prospective multicentre cohort study was conducted using data from 504 residents (63 men; mean age: 87.4 ± 7.8 years) in Japanese long-term care facilities. Basic information, medical history, willingness to engage in oral hygiene behaviour, need for OHM and oral conditions were investigated at baseline. In addition, information on the occurrence of pneumonia was collected using a follow-up survey after one year. A Poisson regression analysis with robust standard errors was conducted, with pneumonia as the dependent variable, and factors associated with OHM and pneumonia occurrence as explanatory variables. RESULTS: Overall, 349 (69.2%) residents required OHM by dental hygienists during that year of follow-up. Of those, 238 (68.2%) were provided with OHM, and 18 (7.5%) developed pneumonia. Among the 111 patients (31.8%) who were not provided with OHM, 21 (18.9%) developed pneumonia. The OHM group had lower pneumonia rates than the non-OHM group (prevalence rate ratio: 0.374; 95% CI: 0.210-0.665). CONCLUSION: Oral health management by dental hygienists was associated with a lower incidence of pneumonia among residents of long-term care facilities, underlining the importance of professional OHM for such individuals. It is recommended that OHM be practised routinely in long-term care facilities.

Relationship between weight loss and regular dental management of older adults residing in long-term care facilities: a 1-year multicenter longitudinal study.

PURPOSE: This study aimed to determine the association between home visits by a dentist and regular oral hygiene management by a dental hygienist (regular dental management: RDM) and weight loss among older adults in long-term care facilities. METHODS: A total of 468 older residents from 26 Japanese long-term care facilities participated in two surveys in 2018 and 2019. Participants were divided into two groups based on their diet during the baseline survey (regular diet, n = 256; dysphagia diet, n = 212). Participants with a regular diet were further divided into those who exhibited a weight loss ≥ 5% over 1 year (weight loss group: n = 77) and those with a weight loss < 5% (consistent weight group: n = 179). The explanatory variables were age, sex, baseline weight, Barthel index, and clinical dementia rating, as well as the patients' medical history of pneumonia, stroke, diabetes, and depression (which is reportedly associated with weight). Additionally, a Poisson regression with robust standard error, was carried out to analyze the explanatory variables, namely the prevalence of RDM noted during the study and functional teeth (which seemed to affect weight loss). RESULTS: A multivariate analysis revealed that older residents' lack of RDM, clinical dementia assessment, and their history of pneumonia (prevalence rate ratio: 0.35, 95% confidence interval 0.24-0.95) were all significantly associated with weight loss when on a regular diet. CONCLUSION: Thus, weight loss and RDM were related to each other. Weight loss may be suppressed by incorporating RDMs during the early nursing care for older residents on regular diets.

Association between Weight Loss and Food Form in Older Individuals Residing in Long-Term Care Facilities: 1-Year Multicenter Longitudinal Study.

Changing the food form for older adults requiring nursing care from a regular to dysphagia diet is thought to impact their nutritional status. We assessed the association between changes in food form and weight loss over 1 year in older adults. Older adults residing in long-term care facilities in Japan (n = 455) who participated in the baseline (2018) and follow-up (2019) surveys were divided into two groups (regular diet, n = 284; dysphagia diet, n = 171). The regular diet group was further divided into the weight loss (n = 80; weight loss ≥5% over 1 year) and weight maintenance (n = 204; weight loss <5%) groups. After 1 year, the Barthel Index significantly decreased, and the proportion of participants who switched from a regular diet to a dysphagia diet significantly increased in the weight loss group than in the weight maintenance group. Multivariate logistic regression analysis found that Barthel index variation (odds ratio (OR): 0.97, 95% confidence interval (CI): 0.94‒0.99), change from a regular diet to a dysphagia diet (OR: 4.41, 95% CI: 1.87‒10.41), and body weight at baseline (OR = 1.06, 95% CI: 1.01‒1.11) were significantly associated with weight loss. Our results suggest that maintaining the food form inhibits weight loss and improves health outcomes in older adults.

Survey of oral hypofunction in older outpatients at a dental hospital.

BACKGROUND: Oral hypofunction is defined as the reversible stage preceding oral dysfunction. However, its assessment and management need further examination and consideration. OBJECTIVE: The present study aimed to examine the current state of oral hypofunction among outpatients at the university hospital. METHODS: New outpatients underwent medical interviews and detailed assessment of oral hypofunction at their initial visit to our dental department. Oral hypofunction was diagnosed if the results of three of the following seven assessment items were below cut-off values: poor oral hygiene, oral dryness, reduced occlusal force, decreased tongue-lip motor function, decreased tongue pressure, decreased masticatory function and deterioration of swallowing function. The relationships between factors used to diagnose oral hypofunction as well as the distributions of assessment values were clarified. RESULTS: Seventy-five of 209 patients (35.9%) were finally diagnosed with oral hypofunction. Diagnosis of oral hypofunction was significantly related to patient age, Eichner index, a chief complaint of dental or periodontal disease or ill-fitting dentures and a history of neurodegenerative disease. The lowest quintile values for poor oral hygiene, oral dryness and decreased masticatory performance were all above current cut-off values. Reduced occlusal force contributed strongly to the diagnosis of oral hypofunction. CONCLUSION: Oral hypofunction in dental outpatients at a university hospital was associated with patient age, medical history and chief complaint at presentation. Diagnosis of oral hypofunction can be closely related to reduced occlusal force. The validity of cut-off values for assessments of oral hypofunction needs further consideration.

Factors associated with xerostomia in perimenopausal women.

OBJECTIVES: Various oral symptoms, including xerostomia and burning mouth syndrome, may occur in menopausal women. These symptoms reduce quality of life (QOL). However, the actual condition of xerostomia after menopause is not clear. The purpose of this study was to reveal the factors associated with xerostomia in perimenopausal women. METHODS: Participants included 118 outpatients (mean age, 49.9 ± 3.2 years; range, 45-55 years) at a department of gynecology in Japan. Information was collected concerning age, medical history, medications, menstrual status, and history of treatment for climacteric symptoms. Oral symptoms, including xerostomia were evaluated with a 3-point scale. The climacteric symptom checklist for Japanese women and 36-Item Short-Form Health were used to evaluate climacteric symptoms and QOL, respectively. In addition, the volume of unstimulated saliva, oral moisture, salivary α-amylase, chromogranin A, and 17-ß estradiol were measured. RESULTS: Higher age, the total number of medications, psychotropic drug, hormone replacement therapy, treatment for climacteric symptoms, sticky mouth, burning sensation of tongue, dryness of nose and 14 of the 21 climacteric symptoms significantly affected xerostomia. In addition, treatment for climacteric symptoms, fall asleep but often awake at night, headaches and dryness of nose were significantly associated with xerostomia. In conclusion, xerostomia is closely associated to factors such as treatment for climacteric symptoms and certain menopausal symptoms, and it may be related to QOL in perimenopausal women.

Menopausal symptoms are associated with oral sensory complaints in perimenopausal women: an observational study.

BACKGROUND: Perimenopausal women experience a wide variety of systemic symptoms: hot flashes, sweating, mental health concerns and various oral sensory complaints (OSC). OSC in perimenopausal women include xerostomia, taste disturbance and burning mouth. However, the factors associated with these OSC have not been identified. The purpose of this investigation was to elucidate the factors associated with OSC in perimenopausal women. METHODS: The study cohort comprised 43 perimenopausal women aged 45-55 years. Data on medical history, medications, menstrual status, menopausal symptoms, quality of life, xerostomia, taste disturbance and burning mouth were collected. Volumes of unstimulated and stimulated saliva were measured. Tongue coating was evaluated according to a tongue coating index. Univariate analysis was performed to identify factors significantly associated with having xerostomia, taste disturbance, burning mouth and more than two OSC (2OSC). Next, the factors strongly associated with these symptoms were examined by logistic regression analysis. RESULTS: The number of menopausal symptoms was significantly higher, and volume of unstimulated saliva was significantly lower in participants with xerostomia, taste disturbance, burning mouth or 2OSC than in those without these characteristics. Agents targeting the central nervous system were more frequently taken by participants with burning mouth and 2OSC than by those without these characteristics. According to logistic regression analysis, the number of menopausal symptoms was an explanatory variable for xerostomia, taste disturbance, burning mouth and 2OSC. CONCLUSIONS: Our findings suggested that OSC associated with the number of menopausal symptoms. Management of menopausal symptoms may decrease OSC, leading to improved quality of life of perimenopausal women.

Changes of bolus properties and the triggering of swallowing in healthy humans.

There is wide variation in chewing behaviours, even among healthy humans. Further, the way in which humans determine swallowing initiation when chewing solid foods remains unclear. The current study sought to investigate how the bolus properties change over time during chewing, and to clarify which factors affect chewing and swallowing behaviours, including swallowing initiation, in healthy humans. Twenty-four healthy volunteers were instructed to chew 8 g of steamed rice and spit it out at 50%, 100% and 150% of their own chewing duration, defined as the time of chewing from onset of the first chewing cycle to onset of the first swallow. Chewing and swallowing behaviours were monitored and determined by visual inspection of video recordings. The physical properties such as hardness, cohesiveness and adhesiveness as well as water content of the bolus were measured. In each subject, maximum bite force, tongue pressure and stimulated salivary flow rate were also measured. Hardness gradually decreased, and the cohesiveness and water content of the bolus did not change up to 50% of chewing duration, followed by a slight but significant increase. The adhesiveness of the bolus rapidly decreased at the beginning of chewing. Chewing duration was significantly related to stimulated salivary flow rate; greater salivary flow rate was associated with shorter chewing duration. Variation of chewing duration and swallowing initiation was not dependent on bolus properties during the chewing of steamed rice, but mainly depended on the surface lubrication of the bolus.

Impact of Oral and Swallowing Function on the Feeding Status of Older Adults in Nursing Homes.

BACKGROUND: To date, there have been few guidelines proposed for adjustment of the food consistency, particularly to match the oral function of older adults, which will guide clinicians and caregivers in appropriately modifying food. OBJECTIVE: We investigated how oral, swallowing, and cognitive conditions of older adults who required daily nursing care in a nursing home were associated with different dietary food consistencies. METHODS: Clinical examinations to record dentition status, swallowing, and cognitive functions were performed, and the feeding status, including the food consistencies and need for assistance at lunchtime, was evaluated in 37 older residents in nursing homes. The swallowing function was assessed by performing a modified water-swallowing test, and food swallowing was tested using pudding and rice crackers. The χ2 test was used to determine the relationships among the parameters. RESULTS: No participants were able to take cooked rice, nor regular and soft side dishes. There was no significant relationship between dentition status and feeding status. Of the participants, 95% ate pudding without any problems and 49% ate rice crackers without any signs of swallowing difficulty such as coughing or stopping chewing. There was a significant relationship between the food test score using a rice cracker and the level of food consistencies, and between the same test score and the level of mealtime assistance, whereby the better the score of the food test using a rice cracker, the better was the level of food consistencies including use of a thickening agent and the better was the level of mealtime assistance. CONCLUSION: The results strongly suggest that the food test using a rice cracker was associated with the level of food consistency and mealtime assistance for older adults in nursing homes.

Effects of Carbonation and Temperature on Voluntary Swallowing in Healthy Humans.

We investigated how swallowing behaviors are affected by the temperature and carbonation of water in healthy humans. Twenty-nine healthy volunteers were instructed to drink as much natural water, carbonated water, or cider as they wanted, and we recorded the volume of solution swallowed and electromyographic (EMG) activity of the masseter and suprahyoid muscles. Sensory tests regarding the ease of holding the solution in the mouth and ease of swallowing were also performed. The volume of carbonated water swallowed was significantly lower than that of natural water and cider. The ease of holding and swallowing the solution significantly differed between solution types such that natural water was the easiest solution to hold and swallow, followed by cider and then carbonated water in both tests. EMG activity was also affected by the solution type. Masseter EMG activity was significantly lower when swallowing natural water compared with carbonated water. Suprahyoid EMG activity was significantly lower when swallowing natural water compared with carbonated water and cider. The volume of solution swallowed was significantly correlated with the ease of holding and swallowing the solution, but not with masseter or suprahyoid EMG activities. The ease of holding and swallowing the solution significantly affected masseter and suprahyoid EMG activities. The results suggested that when participants experienced difficulty holding and swallowing the solution, masseter and suprahyoid EMG activity increased. Considering our findings that mechanical stimulation with bubbles decreased the volume of solution swallowed and increased EMG activities, carbonated water swallowing may be useful in treating deglutition disorders.

Radiological imaging features of the salivary glands in xerostomia induced by an immune checkpoint inhibitor.

The clinical features of xerostomia induced by immune checkpoint inhibitors (ICI) are similar to those of Sjögren's syndrome (SS), whereas the immunohistological and serological features are known to differ from those of SS. However, the radiologic imaging features of salivary glands are not yet well known. We report a case of a 56-year-old male patient diagnosed with ICI-induced xerostomia. The patient underwent various imaging examinations to investigate the condition of the salivary glands, which indicated the following: (1) less specific findings on contrast-enhanced computed tomography, (2) mixed with intermediate and low signal intensity on both T1-weighted and fat-suppressed T2-weighted magnetic resonance imaging and poor "salt and pepper" appearance on magnetic resonance sialography, and (3) multiple ovoid hypoechoic areas with hyperechoic bands without acute sialadenitis on ultrasound. These radiologic imaging findings suggested remarkable lymphocyte infiltration, which could be a characteristic of ICI-induced xerostomia.