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.
Maximum bite force (MBF) is a common and useful index of masticatory function; it correlates with physical strength in elderly people. Palpation of stiffness in the masseter muscle during forceful biting has been considered to be associated with MBF. However, this assessment method relies on subjective judgments; no study has verified the relationship between MBF and quantitative measurements of masseter muscle stiffness (MMS).We aimed to verify the association between masseter muscle myotonometric assessment results and MBF.In total, 117 community-dwelling >65-year-old individuals from the Tokyo metropolitan area were assessed. MMS on the dominant side during forceful biting was measured with a MyotonPRO device. Masseter muscle thickness (MMT) during rest and forceful biting was measured with an ultrasonic diagnostic apparatus, and the difference in MMT (DMMT) between the rest and forceful biting conditions was determined. MBF data were obtained with a pressure-sensitive sheet and an associated device. To determine the independent variables affecting MBF and MMS, multivariate linear regression analyses with adjustments for age, sex and number of teeth were performed.The multivariate analysis revealed that MBF correlated with the number of teeth (β = .489, P < .001) and MMS (β = .259, P = .003) (R2 = .433). MMS correlated with MBF (β = .308, P = .003) and DMMT (β = .430, P < .001) (R2 = .326).Masseter muscle stiffness possibly reflects a force generated by the masseter muscle during forceful biting. Therefore, MMS is effective to assess tooth loss as well as an index of masseter muscle strength when evaluating MBF.
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.
The aim of this study was to clarify the relationship among swallowing function, activity, and quality of life (QOL) in older adults with low activities of daily living (ADL).We conducted a cross-sectional study. In total, 271 Japanese adults aged over 65 years who underwent medical intervention at their residence (male: n = 107; female: n = 164; mean age = 84.6 ± 8.3 years) participated. We collected data regarding age, sex, body mass index (BMI), residence (their house/nursing home), activity status, consciousness level (eye response), history of aspiration pneumonia, other medical history, number of medication types, frequency of going out, and time spent away from bed. We judged consciousness level (eye response) using the Glasgow Coma Scale (GCS), calculated the Charlson comorbidity index, measured QOL using the short version of the Quality of Life Questionnaire for Dementia (short QOL-D), and assessed swallowing function using the Functional Oral Intake Scale (FOIS). To examine the relationship between scores for the FOIS and the other variables, we used the Spearman rank correlation coefficient and ordinal logistic regression analysis.The FOIS was strongly correlated with BMI (ρ = 0.47), activity status (ρ = -0.60), GCS (ρ = -0.41), time spent away from bed (ρ = 0.56), scores for the short QOL-D (ρ = 0.40), weakly correlated with history of aspiration pneumonia (ρ = -0.27), and frequency of going out (ρ = 0.39). Results for the ordinal logistic regression analysis showed that the FOIS was associated with activity status, frequency of going out, time spent away from bed, and scores for the short QOL-D.The swallowing function of older adults with low ADL was related to their QOL and activities, such as time spent away from bed and home. Thus, in rehabilitation programs for swallowing function in older adults, not only functional but also psychological approaches may prove effective.
Abstract In clinical practice, we encounter cases wherein older adults lacking occlusal support consume foods requiring mastication and adequate swallowing function. This study investigated the relationship between jaw-closing force (JCF) and dietary form in older adults without occlusal support requiring nursing care. This prospective cross-sectional study included 123 older adults requiring nursing care who lost their molar occlusal support and consumed food orally without dentures. JCF was defined as the force required for crushing food with the edentulous ridges or with the tooth and edentulous ridge while closing the mouth. Participants were classified into four groups based on the International Dysphagia Diet Standardization Initiative framework for recommended dietary forms. Basic information was collected, and tongue pressure and JCF were measured. Differences in JCF were analyzed using one-way analysis of variance, while factors related to dietary form were evaluated using ordinal logistic regression analysis. Significant differences in JCF were observed among the four groups. Factors such as the Barthel Index, tongue pressure, and JCF were dietary form-related. Our findings suggest that older adults requiring nursing care tend to have higher JCF when consuming meals requiring mastication. Therefore, JCF could serve as an index for determining appropriate dietary forms in this population.
Dysphagia is one of the postoperative complications of cervical degenerative disorders. However, few studies have evaluated the pre- and postoperative swallowing function in detail.To analyze pre- and postoperative swallowing dynamics kinetically and investigate factors associated with postoperative dysphagia in patients with cervical degenerative disorders.Retrospective review of prospectively collected data.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).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.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.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).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.
Fall Risk Index (FRI), consisting of 21 simple yes/no questions, has been shown to successfully screen community-dwelling older Japanese for fall risk. To identify the fall-prone inpatients effectively, we examined additional risk factors besides FRI. We retrospectively investigated 253 inpatients in the University of Tokyo Hospital, discharged from April 2016 to March 2017, mainly hospitalized for cognitive impairment or acute illness such as pneumonia. The data include patients’ characteristics, FRI and a history of falls in the year before admission. T-tests, chi-square tests, linear and logistic regressions and receiver operating characteristic (ROC) curves were used for evaluating strong fall risk factors in addition to FRI. Eighty-eight inpatients (46.7% in 165 patients) fell in the year preceding admission. The FRI ranged from 0 to 20 (mean 11 ± 4). Between fallers and non-fallers, the differences were significant in age, serum albumin, FRI, Mini Mental State Examination (MMSE), Specific Activity Scale, Barthel index and Lawton Instrumental Activities of Daily Living Scale. In logistic regression with these variables and sex, cognitive impairment by low MMSE (≦23/30 points) and men showed positive trends toward fall. In the stepwise linear regression with age, sex and FRI, only MMSE was selected in the model. Adjusted for age, sex, serum albumin and FRI, cognitively impaired patients showed fall odds of 2.57 (95%CI 1.10–6.02). The area under the ROC curve was the largest for FRI (0.77) in the cognitively impaired population. Therefore, additionally to FRI, cognitive impairment should be taken into account to assess fall risk for inpatients.