Kinematic analysis of chewing and swallowing function after cervical spine surgery.

PURPOSE: Although movement of the hyoid bone is different for masticatory swallowing and liquid swallowing in normal subjects, it has not been studied after cervical spine surgery. Therefore, we analyzed the swallowing dynamics of masticatory swallowing in anterior cervical spine disease surgery using foods that require chewing close to actual meals. METHODS: A day before and one week after the surgery, a videofluoroscopic swallow study (VFSS) was performed, and the distance of hyoid bone movement in the anterior and superior directions, amount of opening of the upper esophageal sphincter (UES), time of passage through the pharynx, number of swallows, and amount of pharyngeal residual were measured on the VFSS images during a masticatory swallow of corn flakes. The swallowing function was evaluated by DSS (dysphagia severity scale) and FOIS (functional oral intake scale). Imaging software was used for the measurements. RESULTS: Postoperative hyoid movement during masticatory swallowing was not significantly different for anterior movement but significantly limited in upward movement (p = 0.002); UES opening volume was significantly decreased (p < 0.001), and bolus residue was significantly worse (p < 0.001), compared to preoperative. The pharyngeal transit time was not significantly different; the number of swallows increased (p < 0.001), along with DSS (p < 0.001) and FOIS (p < 0.001), with significant differences before and after surgery, indicating worsened swallowing function. CONCLUSIONS: Swallowing function worsened in masticatory swallowing after surgery for cervical spine disease, mainly due to the restriction of upward movement of the hyoid bone and the resulting increase in pharyngeal residuals after swallowing.

Tongue Strength of Older Adults Requiring Long-Term Care Varies throughout the Day.

Physical performance shows approximately 30% diurnal variation; however, diurnal variation in oral function remains unclear. This study aimed to determine the diurnal variation in oral and swallowing function in older adults requiring long-term care. The participants included 13 adults aged >60 years (3 men and 10 women, mean age: 77.2 ± 6.3 years, age range: 62-90 years) requiring long-term care. Tongue strength (TS) and oral mucosal moisture were measured as indices of oral and swallowing function, while hand grip strength was measured as an index of general muscle strength. The patients were asked to participate in a "test" after breakfast, lunch, and dinner on the same day. Multilevel linear regression analysis was used to examine diurnal differences in each item. Multilevel linear regression analysis with adjustment for age and sex revealed that TS was significantly higher at noon (p = 0.001) than in the morning. Therefore, caregivers who provide support during meals to older people requiring long-term care should consider the possibility of swallowing function differing according to the time of the day. In conclusion, it may be beneficial to establish a nutritional therapy that accounts for the diurnal variation in TS.

Free-flap volume correlates with body mass index in patients with tongue squamous cell carcinoma.

Objectives: This study aimed to investigate the relationship between postoperative reconstructed tongue flap volume (RTFV) and body mass index (BMI) and identify factors affecting the flap volume in patients with tongue squamous cell carcinoma. Methods: Thirty-two patients were evaluated for RTFV from computed tomography images and BMI. The first and second evaluations were done at 6 months and 1.5 years after surgery respectively. RTFV rate changes and BMI differences from the first and second evaluations were calculated. The correlation between RTFV rate change and BMI difference was assessed using Spearman's rank correlation coefficient. Multiple regression analysis evaluated the relationship between the flap volume rate change and age, sex, flap type, and BMI difference to identify influencing factors. Results: The flap volume rate change and BMI difference correlated significantly (r = .594, p < .05). BMI difference and flap type were independent factors that affected reconstructed flap volume rate change in multiple regression analysis (p < .05). Conclusion: The flap volume of patients with tongue squamous cell carcinoma correlates with the BMI change in the chronic phase. Patients after tongue reconstruction need to be well nourished to maintain BMI and thus postoperative tongue volume to maintain the quality of life. Level of Evidence: Level 3.

Evaluation of preventive care for swallowing difficulty through policy changes in Japanese long-term care insurance: analysis of a nationwide claims dataset for long-term care insurance.

BACKGROUND: Swallowing/feeding difficulty is a serious hidden health problem in the older population. Although oral intake services based on the degree of this difficulty have been provided and revised in Japanese public long-term care (LTC) insurance since 2006, their implementation has not been examined. We evaluated the impact of policy changes on these services. METHODS: The nationwide database of LTC service uses in Japan was analysed for three oral intake services: Enhanced Oral Function in daycare facilities whose users were slightly disabled, Maintenance of Oral Ingestion and Transition to Oral Ingestion from tube feeding in residential facilities. Data were extracted for each June from 2015 to 2020 when monthly usage of these services was aligned and each June from 2009 to 2020 for the proportion of users according to LTC insurance certification. The major policy changes were the addition of municipal provision in Enhanced Oral Function and a requirement for multidisciplinary collaboration in Maintenance of Oral Ingestion in 2015. The impact of the medical fee reduction for developing percutaneous gastro-tubing to Transition to Oral Ingestion was also examined. RESULTS: Between 2015 and 2020, the use of Enhanced Oral Function and Maintenance of Oral Ingestion increased and Transition to Oral Ingestion decreased, resulting in a total increase in use of 275,000 times or approximately 5,000 times per 100,000 among all older adults with LTC insurance certification. Concerning the proportion of users' disability status, the major users of Enhanced Oral Function in 2020 were slightly disabled and independent older adults (70%, up from 55% to 2009). Regarding the major users of Maintenance of Oral Ingestion between 2013 and 2020, care-need level 5 (most severe) decreased by 11%, whereas the total of care-need levels 4 and 3 increased by 9%. The use of Transition to Oral Ingestion, which had been declining, showed a further decline after reduction of the medical fee for percutaneous gastro-tubing in 2014. CONCLUSIONS: Due to policy changes, Enhanced Oral Function and Maintenance of Oral Ingestion have increased in the number of use among slightly disabled persons. However, this increase may be insufficient given the hidden swallowing/feeding difficulty.

Factors influencing the selection of oral healthcare providers in multidisciplinary Nutrition Support Team for malnourished inpatients: A cross-sectional study.

BACKGROUND: Oral health management involving dental professionals in a multidisciplinary Nutritional Support Team (NST) is effective collaborative care. However, the indicators for the triage of oral health management requirements and selection of oral healthcare providers remain unclear. OBJECTIVE: This cross-sectional study included inpatients with malnutrition and aimed to investigate the factors associated with determining the need for oral health management involving dental professionals and selecting primary oral healthcare providers when needed. METHODS: Participants included 255 inpatients (154 males and 101 females, mean age 69.7 ± 14.4 years) aged ≥20 years who underwent oral assessment by the NST between April 2016 and July 2019. Participants were assigned to the following groups: good oral health group, oral health management by nurses under the supervision of dental professionals group, and oral health management by dental professionals group. The comprehensive oral health status was investigated using the Oral Health Assessment Tool (OHAT). The total OHAT score ranges from 0 to 16, with a higher score indicating a poorer oral environment. RESULTS: The total OHAT score had a significant correlation with the need for oral health management by dental professionals. Inpatients with denture problems required oral health management from dental professionals. The optimal cutoff value of the total OHAT score for determining the need for oral health management was four. CONCLUSION: The need for oral health management by dental professionals increased with worsening oral health status, especially denture problems. The OHAT score could be used to triage inpatients who require oral health management collaborated with dental professionals.

Factors Related to Oral Problems in Patients with Prolonged Disorders of Consciousness in Long-Term Care: A Cross-Sectional Study.

Factors influencing oral problems, such as malocclusion and oral motor dysfunction, in patients with prolonged disorders of consciousness (DOC) remain unclear. This study aimed to clarify the relationship between oral problems and physical function, communication, respiration, and oral intake status, as well as related factors in patients with DOC receiving long-term care at home. A cross-sectional study was conducted in October 2018; 127 patients who developed DOC > 5 years ago were analyzed. The differences between patients with and without oral problems were examined, and a binomial logistic regression analysis was performed to examine factors associated with oral problems, with the presence of oral problems as the dependent variable, and age, the number of years since onset, drooling, oral intake status, and the presence of a family dentist as explanatory variables. A post hoc power analysis of the binomial logistic regression analysis for oral problems (odds ratio: 2.05, alpha value: 0.05, incidence of oral problems: 0.80, and total sample size: 127) demonstrated an observed power of 93.09%. Oral intake status (p = 0.010) and the number of years since onset (p = 0.046) were significantly related to oral problems. Preventive oral management and rehabilitation from the early stage after onset may be effective for oral problems in patients with DOC.

Association between characteristics of swallowing-related muscles and trunk muscle mass.

Swallowing function is associated with systemic factors. Whether trunk or appendicular skeletal muscle mass is a better indicator of swallowing-related muscle characteristics in community-dwelling older adults is not clear. Hence, we investigated the association between the characteristics of swallowing-related muscles (e.g., mass and quality) and trunk muscle mass. Community-dwelling older adults aged ≥ 65 years (n = 141; men: n = 45, women: n = 96) were recruited for this cross-sectional observational study via a health survey conducted in 2018. Trunk muscle mass index (TMI) and appendicular skeletal muscle mass index (SMI) were measured using bioelectrical impedance analysis. Cross-sectional areas (CSAs) and echo intensity (EI) of the geniohyoid muscle (GHM) and tongue were evaluated using an ultrasonic diagnostic apparatus. Multiple regression analysis was used to examine the relationship of the characteristics of swallowing-related muscle with TMI and SMI. Multiple regression analysis showed that CSA of the GHM was positively associated with both TMI (B = 24.9, p < 0.001) and SMI (B = 13.7, p = 0.002). EIs of swallowing-related muscles were not associated with TMI and SMI. Trunk muscle mass was associated with swallowing-related muscle mass and not muscle quality. The results of this study shed light on the elucidation of association of dysphagia with TMI and SMI.

The Safety of Oral Rehydration Solution Jelly for Water and Electrolyte Intake in Patients with Dysphagia.

Purpose: Oral rehydration solutions (ORSs) are effective in replacing fluids and electrolytes and are widely used. OS-1 Jelly (Otsuka Pharmaceutical Factory, Tokushima, Japan) is a jelly drink corresponding to code 2-1 of the 2021 Japanese Dysphagia Diet. Although jelly drinks are less likely to be aspirated than liquids, their physical properties vary depending on the product. Therefore, the severity of dysphagia may affect intake status. This study aimed to investigate the association between the intake status of ORS jelly and swallowing function. Patients and Methods: Thirty-six patients with dysphagia who required videoendoscopic swallowing evaluation at our university hospital were enrolled. Videoendoscopic swallowing evaluation was performed, and each participant swallowed 5 mL of OS-1 Jelly or thickened water modified to International Dysphagia Diet Standardization Initiative (IDDSI) level 2 three times. Statistical analysis was performed to determine the difference in the number of swallows, time until the swallowing reflex, position for inducing the swallowing reflex, presence of pharyngeal residue, penetration, or aspiration between ORS jelly and thickened water. Results: The time until the swallowing reflex was induced and the position of the swallowing reflex triggered were significantly earlier for ORS jelly (p=0.012, p=0.001). The incidence of pharyngeal residue was significantly lower with ORS jelly (p=0.002). The Penetration-Aspiration Scale score was similar for both samples (p=0.062), and no aspiration was observed in either sample. Conclusion: Patients with dysphagia who can swallow thickened water modified to IDDSI level 2 can consume ORS jelly. ORS jelly, which requires no thickening and can be easily and safely consumed, is effective for water and electrolyte intake in patients with dysphagia.

Effects of tongue right positioner use on tongue pressure: a pilot study.

The effectiveness of the tongue right positioner (TRP) use on oral and swallowing functions remains unclear. To investigate the effects of TRP use on tongue function in patients with dysphagia. This interventional study included eight participants with dysphagia who visited a university dental hospital. The measurement variables included tongue pressure (TP) as the primary outcome and lip and tongue movements, peak nasal inspiratory flow, and changes in the tongue and suprahyoid muscle regions on ultrasonography as the secondary outcomes. Each participant was asked to use a TRP for at least 8 h every night for 2 months. The measurement variables before and after the intervention were compared using the paired t test and Wilcoxon signed-rank test. TP after intervention (31.5 ± 13.1 kPa) was significantly higher than that before intervention (23.0 ± 13.4 kPa), while other measurement variables did not significantly improve. Numerous exercises have been suggested to improve TP; however, most require patients' adherence to instructions. In contrast, although participants did not perform active exercises, most participants in this study observed an improved TP. Our findings show that TRP can greatly improve TP after 2 months of usage.Trial registration number: University Hospital Medical Information Network Clinical Trials Registry (UMIN000040253, date of first registration: 27/04/2020).

Associations of swallowing-related muscle quantity and quality with sarcopenic parameters.

PURPOSE: To examine the associations between swallowing-related muscle characteristics and sarcopenic parameters. METHODS: We included 147 community-dwelling older adults (age: 71.6 ± 4.7 years, body mass index: 23.0 ± 2.7 kg/m2 (mean ± standard deviation), men: 50; women: 97) and categorized them into robust (n = 125), low-function (n = 17), and sarcopenia (n = 5) groups based on the diagnostic criteria of the Asia Working Group for Sarcopenia 2019. We evaluated the geniohyoid muscle (GHM) and tongue characteristics (muscle quantity and quality). The cross-sectional area (CSA) indicated the muscle quantity, and echo intensity (EI) values indicated the muscle quality. A multiple regression analysis was performed to clarify the relationship of swallowing-related muscle characteristics and strength with sarcopenic parameters. RESULTS: The grip strength (CSA of GHM: ß = 1.64, p = 0.03) and skeletal muscle mass index (CSA of tongue: ß = 74.81, p = 0.003, EI of tongue: ß = 1.92, p = 0.009) were better indicators of swallowing-related muscle characteristics. CONCLUSION: These findings may facilitate the early detection of aging-related deterioration in swallowing-related musculature through the diagnostic process of sarcopenia and increase our understanding of muscle physiology.

Time Spent Away from Bed to Maintain Swallowing Function in Older Adults.

INTRODUCTION: The aim of this study was to determine the associations of time spent away from bed with whole-body muscle mass and swallowing function in older adults with low activities of daily living (ADL). METHODS: This cross-sectional study was conducted at Tokyo Medical and Dental University and included adults over 65 years of age who underwent a medical intervention at their residence. Data regarding age, sex, body height and weight, activity status, medical history, time spent away from bed, and Functional Oral Intake Scale (FOIS) were collected. We calculated the body mass index, Charlson Comorbidity Index, whole-body muscle mass, the appendicular skeletal muscle mass index (ASMI), and the trunk muscle mass index (TMI). According to the time spent away from bed, the subjects were grouped as follows: <4 but ≥0 h (S), <6 but ≥4 h (M), and ≥6 h (L). These variables were analyzed using the one-way analysis of variance, the Kruskal-Wallis test, and the χ2 test, then differences among the three groups were examined. To adjust for confounding factors, we performed multiple regression analysis with ASMI and TMI as the dependent variables and ordinal logistic regression analysis with FOIS as the objective variable. RESULTS: Ninety subjects (male: n = 42; female: n = 48; mean age = 82.9 ± 8.8 years, and groups S: n = 23; M: n = 30; L: n = 37) were analyzed. Group L had a significantly higher ASMI, TMI, and FOIS score than groups S and M, while group M had a significantly higher ASMI and FOIS score than group S. After adjusting for confounding factors, the significant explanatory factors for ASMI were sex, activity status, time spent away from bed, and TMI. The factors for TMI were activity status, time spent away from bed, ASMI, and FOIS. The factors for FOIS were time spent away from bed and TMI. CONCLUSION: Spending 4 or more hours away from the bed is related to appendicular skeletal muscle mass and FOIS, while spending 6 or more hours is related to appendicular skeletal muscle mass, trunk muscle mass, and FOIS in this population. These findings highlight factors that can prevent a decline in swallowing function in the daily life of older adults with low ADL who have difficulty performing exercises to preserve swallowing function.

Higher extracellular water/total body water ratio is associated with lower tongue and grip strength: A cross-sectional study.

PURPOSE: This study aimed to investigate the relationship between tongue factors (tongue strength and tongue volume), systemic factors (grip strength and walking speed), and the extracellular water/total body water ratio. METHODS: This cross-sectional study included community-dwelling adults. Body water composition and skeletal muscle mass index were measured using bioelectrical impedance analysis. Moreover, tongue grip strength, tongue volume, occlusal support condition (Eichner classification), and walking speed were measured. Multiple linear regression analysis was performed to investigate the relationship between the tongue and systemic factors as dependent variables and body water composition. RESULTS: We included 171 community-dwelling adults (62 men and 109 women) aged 70.0 years (interquartile range: 8). Tongue strength (r=-0.22, P=0.004) and grip strength (r=-0.39, P<0.001) were correlated with the extracellular water/total body water ratio. In multiple linear regression analysis, tongue strength was associated with the extracellular water/total body water ratio (ß=-0.20, P=0.034), and grip strength was associated with the extracellular water/total body water ratio (ß=-0.12, P=0.047), sex, body mass index, skeletal muscle mass index, and occlusal support condition. CONCLUSIONS: A higher extracellular water/total body water ratio indicates lower tongue and grip strength. Dentists and dental hygienists should be aware of systemic factors present in patients with lower tongue and grip strength. These findings may lead to further medical investigations and diagnosis of other systemic diseases.

Analysis of swallowing function after anterior/posterior surgery for cervical degenerative disorders and factors related to the occurrence of postoperative dysphagia.

BACKGROUND CONTEXT: Dysphagia is one of the postoperative complications of cervical degenerative disorders. However, few studies have evaluated the pre- and postoperative swallowing function in detail. PURPOSE: To analyze pre- and postoperative swallowing dynamics kinetically and investigate factors associated with postoperative dysphagia in patients with cervical degenerative disorders. STUDY DESIGN: Retrospective review of prospectively collected data. PATIENT SAMPLE: A total of 41 consecutive patients who underwent an anterior approach (anterior cervical discectomy/corpectomy and fusion (ACDF, ACCF), hybrid surgery (ACDF+ACCF) and total disc replacement) and 44 consecutive patients who underwent a posterior approach (laminoplasty and laminoplasty/laminectomy with fusion). OUTCOME MEASURES: We compared the pre- and postoperative functional oral intake scale (FOIS), dysphagia severity scale (DSS), esophageal dysphagia, anterior/superior hyoid movement, upper esophageal sphincter (UES) opening, pharyngeal transit time, bolus residue scale (BRS), and the number of swallows. METHODS: Videofluoroscopy was performed on the day before surgery and within two weeks after surgery. Data related to age, gender, disease, surgical procedure, surgical site, operative time, and blood loss were collected from the medical records. Pre- and postoperative data were compared for each item in the anterior and posterior approaches. The odds ratio of dysphagia after an anterior approach was also calculated. RESULTS: In the anterior approach, DSS, FOIS, the anterior and superior hyoid movements, maximum UES opening, BRS, and number of swallows worsened postoperatively (p<.05, respectively). In the posterior approach, DSS, FOIS, the anterior hyoid movement, and BRS worsened postoperatively (p<.05, respectively). The factors associated with dysphagia were a proximal surgical site above C3 (OR: 14.40, CI: 2.84-73.02), blood loss >100 mL (OR: 9.60, CI: 2.06-44.74), an operative time >200 minutes (OR: 8.18, CI: 1.51-44.49), and an extensive surgical field of more than three intervertebral levels (OR: 6.72, CI: 1.50-30.07). The decline in swallowing function after the posterior approach was related to aging (p=.045). CONCLUSIONS: Each approach may decrease swallowing function, especially because of the limitation on the anterior hyoid movement. Dysphagia after anterior approaches was associated with the operative site, operative time, and blood loss.

Usefulness and Validity of a Jaw-Closing Force Meter in Older Adults.

We prototyped a new device with a soft and flexible pressure sensor to measure the force to close the mandible with or without occlusal support (jaw-closing force, JCF). This study aimed to clarify the practicality of this instrument. Healthy young and older adults with occlusal support were recruited. Intra- and inter-rater reliability of the JCF meter was examined using data from younger participants. Data regarding age, sex, body mass index, remaining teeth, and dentures of the older adults were obtained. Furthermore, the right and left JCFs were measured using a JCF meter; occlusal force was measured using an existing occlusal force-measuring device. Intra- and inter-rater correlation coefficients were significantly reproducible (0.691−0.811, p < 0.05). JCF was correlated with occlusal force (p < 0.05). Multiple regression analysis revealed that factors significantly associated with JCF included denture status (p < 0.001), age (p = 0.038), and occlusal force (p = 0.043). The prototyped JCF meter can measure JCF with high reproducibility, reliability, and validity. Further, association with occlusal force, which is an existing index, was observed. This device could be used to measure the JCF with or without occlusal support as a new method of evaluating oral function in older adults.

Effects of thickened carbonated cola in older patients with dysphagia.

Carbonated beverages initiate the swallowing reflex earlier than water and have a shorter pharyngeal transit time. However, the effects of carbonation in thickened beverages of the same flavor on swallowing dynamics have not been reported. Therefore, we investigated the effects of thickened carbonated beverages on swallowing in patients with dysphagia by comparing the swallowing dynamics between thickened carbonated and thickened non-carbonated beverages. We enrolled 38 patients with dysphagia and divided them into two groups. Thickened carbonated and thickened non-carbonated beverages were used. Videoendoscopic swallowing evaluations were performed. Aspiration, penetration, pharyngeal residue, and initiation position of the swallowing reflex were evaluated. The reduction in the amount of residue in both the vallecula (p = 0.007) and pyriform sinus (p = 0.004) was greater after ingestion of thickened carbonated cola than thickened non-carbonated cola. The onset of the swallowing reflex was significantly earlier after ingestion of thickened carbonated cola than thickened non-carbonated cola (p = 0.007). There were no significant differences in the extent of penetration. Thickened carbonated beverages positively affected swallowing compared with thickened non-carbonated beverages. Thus, the use of thickened carbonated beverages may be helpful for patients with dysphagia.

Strength and morphology of a suprahyoid muscle and their relationship to forward head posture in healthy older adults.

AIM: Forward head posture, an abnormality in head and trunk positioning, adversely affects suprahyoid muscle activity. Jaw-opening force, which reflects suprahyoid muscle strength, is a useful index of dysphagia. However, the relationship between forward head posture and strength and morphology of suprahyoid muscles remains unclear. This study aims to clarify the relationship between forward head posture, jaw-opening force and morphology of suprahyoid muscles. METHODS: During October 2018, we enrolled older adults aged ≥65 years. The craniovertebral angle was measured, and an angle <49° was defined as forward head posture. Jaw-opening force was also measured. The geniohyoid muscle (GHM) was selected to represent the suprahyoid muscles, and its cross-sectional area and length were measured using ultrasonography. Sarcopenia was also determined based on the criteria of the 2019 Asian Working Group for Sarcopenia. Multiple regression analyses were conducted to determine the association between morphological characteristics of the suprahyoid muscle and jaw-opening force as well as the association between the former and forward head posture. RESULTS: Data of 87 participants were analyzed. Sex, cross-sectional area and length of the GHM, and sarcopenia were significantly associated with jaw-opening force. In addition, sex and forward head posture were significantly associated with the length of the GHM. CONCLUSIONS: Our study demonstrated that an overextended length of suprahyoid muscles mediates the relationship between forward head posture and jaw-opening force. Forward head posture is easily visualized and can be a useful indicator of decline in suprahyoid muscle strength. Geriatr Gerontol Int 2022; 22: 779-784.

Changes in Nutrition-Intake Method and Oral Health through a Multidisciplinary Team Approach in Malnourished Older Patients Admitted to an Acute Care Hospital.

Malnourished older inpatients referred to a nutrition support team (NST) usually receive multidisciplinary oral health management during NST intervention. However, the effects of multidisciplinary oral health management on the nutrition-intake method and oral health in these patients remain unclear. This longitudinal study aimed to investigate the effects of NST-mediated multidisciplinary oral health management on the nutrition-intake methods, oral health, and the systemic and oral factors influencing the changes in the nutrition-intake method. A total of 117 inpatients (66 men, 51 women, mean age, 71.9 ± 12.5 years) who underwent NST-mediated multidisciplinary oral health management between April 2016 and July 2019 were enrolled. Demographic data and Functional Oral Intake Scale (FOIS), Dysphagia Severity Scale (DSS), and Oral Health Assessment Tool (OHAT) scores at the time of referral to the NST and completion of the NST intervention were evaluated. After multidisciplinary NST intervention, FOIS, DSS, and OHAT scores showed significant improvements (p < 0.001). Even after adjusting the results for systemic parameters, FOIS score improvement correlated positively with the length of NST intervention (p = 0.030) and DSS score improvement (p < 0.001) as well as OHAT score improvement (p = 0.047). NST interventions with multidisciplinary oral health management could improve the nutrition-intake method.

Cough Test Results during Screening for Silent Aspiration Are Affected by Risk Factors for Silent Cerebral Infarct in Older Adults with Chronic Disease.

The cough reflex does not change with age. However, older adults with chronic diseases often have a reduced cough reflex. The effects of several risk factors on reduced cough sensitivity in older adults remain unclear. This study aims to clarify the risk factors for reduced cough sensitivity in older adults with chronic diseases. This cross-sectional study included participants aged <65 years (young group; n = 21), those aged ≥65 years (older adults with chronic disease group; n = 18), and those with dysphagia (dysphagia group; n = 16). A cough test was performed on all participants using an ultrasonic nebulizer with a mist of 1% w/v citric acid physiologic saline. Cough response was observed in the young (21/21), older adult (9/18), and dysphagia (13/16) groups. The difference between the young and older adult groups was significant (p < 0.01). The older adult and dysphagia groups had decreased cough sensitivity compared to the younger group. Cough sensitivity was affected by risk factors for silent cerebral infarct and age. Our findings show that cough test results might be affected by risk factors for silent cerebral infarction in older adults with chronic diseases.

The Cross-Sectional Area of the Middle and Base of the Tongue is Associated with Swallowing-Related Muscle Strength.

Muscle strength and function are generally positively correlated with muscle quantity and negatively correlated with muscle quality; however, the tongue shows a unique tendency, different from limb muscles. The relationship between the characteristics of each part of the tongue, muscle strength and function, and systemic factors has been unclear. The aim of the study was to investigate the relationship between cross-sectional area (CSA) and echo intensity (EI) of the middle and base of the tongue and swallowing, articulation function, and body composition. Eighty-nine healthy individuals were included in this cross-sectional study. Swallowing was assessed using tongue pressure (TP) and jaw opening force (JOF) as they indicate swallowing-related muscle strength. Articulation function was evaluated through oral diadochokinesis (ODK). Bioelectrical impedance analysis was performed for body composition. CSAs and EIs of the middle and base of the tongue were measured using ultrasound. Multiple regression analysis was used to examine the relationship between the characteristics of the tongue, swallowing-related muscle strength, and ODK. In multiple regression analysis with TP as the dependent variable, age (ß = - 0.22, P < 0.01) and CSA of the middle part (ß = 0.02, P < 0.01) were significant explanatory variables. In multiple regression analysis with JOF as the dependent variable, sex (ß = - 2.76, P < 0.01) and CSA of the base (ß = - 0.004, P < 0.05) were significant explanatory variables. Multiple regression analysis with articulation function as the dependent variable did not yield significant results. The CSA of the tongue is a better indicator of swallowing-related muscle strength than EI. Ultrasonography may be used for assessing swallowing-related muscle strength.