Influence of aging on extracellular water-to-total body water ratio in community-dwelling females.

BACKGROUND & AIMS: The European Working Group of Sarcopenia in Older People 2 has emphasized the significance of evaluating not only muscle mass but also muscle quality as a diagnostic criterion for sarcopenia. The extracellular water-to-total body water ratio (ECW/TBW), measured using bioelectrical impedance analysis (BIA), has recently received attention as an indicator of muscle quality. However, the influence of aging on the ECW/TBW remains unclear. If ECW/TBW increases with age, it is important to know whether the timing of the decrease in SMI and the increase in ECW/TBW are the same or different. This study aimed to investigate the influence of aging on ECW/TBW in community-dwelling females. METHODS: This cross-sectional study included 237 community-dwelling females aged 20-89 years who could perform activities of daily living independently. ECW/TBW and SMI were measured using BIA. Multiple linear regression analyses of ECW/TBW and SMI were conducted. Age, body mass index (BMI), number of medications, pain, and medical history were considered independent variables in the multiple linear regression. The participants were divided into three (20-39, 40-64, and 65-89 years) or four (20-39, 40-64, 65-74, and 75-89 years) groups based on age. Analysis of covariance adjusted for the BMI, number of medications, pain, and medical history was conducted to determine the differences in ECW/TBW and SMI among the three or four groups. RESULTS: In the multiple linear regression analysis, age was significantly and independently associated with ECW/TBW and SMI. When the participants were divided into three groups based on age, an increase in ECW/TBW and a decrease in SMI in the 65-89-year group were confirmed compared with the 20-39 and 40-64-year groups. When the participants were divided into four groups based on age, an increase in ECW/TBW in the 75-89-year group was confirmed compared with the 65-74-year group. However, there were no significant differences in SMI among the four groups. CONCLUSIONS: This study revealed that ECW/TBW increases with aging in community-dwelling females. Moreover, the negative influences of aging were confirmed earlier in ECW/TBW than in SMI. Assessing muscle mass alone may not be adequate to capture the influences of aging on muscle composition, and evaluating ECW/TBW may be crucial for diagnosing sarcopenia.

Increased intramuscular adipose tissue of the quadriceps at admission is more strongly related to activities of daily living recovery at discharge compared to muscle mass loss in older patients with aspiration pneumonia.

BACKGROUND: Recent studies reported that an increase in intramuscular adipose tissue of the quadriceps in older patients negatively affects the recovery of activities of daily living (ADL) more than the loss of muscle mass. However, whether intramuscular adipose tissue of the quadriceps in older patients with aspiration pneumonia is related to ADL recovery remains unclear. This study aimed to determine the relationship between intramuscular adipose tissue of the quadriceps and ADL recovery in older patients with aspiration pneumonia. METHODS: Thirty-nine older inpatients who were diagnosed with aspiration pneumonia participated in this prospective study. The main outcome of this study was ADL at discharge. ADL were assessed using the Barthel Index (BI). The intramuscular adipose tissue and muscle mass of the quadriceps were evaluated at admission using echo intensity and muscle thickness observed on ultrasound images. A multiple linear regression analysis was performed to confirm whether the quadriceps echo intensity was related to the BI score at discharge, even after adjusting for confounding factors. RESULTS: The medians [interquartile range] of the BI score at admission and discharge were 15.0 [0.0-35.0] and 20.0 [5.0-55.0], respectively. The BI score at discharge was significantly higher than that at admission (p = 0.002). The quadriceps echo intensity (ß = - 0.374; p = 0.036) and BI score at admission (ß = 0.601; p < 0.001) were independently and significantly related to the BI score at discharge (R2 = 0.718; f2 = 2.546; statistical power = 1.000). In contrast, the quadriceps thickness (ß = - 0.216; p = 0.318) was not independently and significantly related to the BI score at discharge. CONCLUSIONS: Increased intramuscular adipose tissue of the quadriceps at admission is more strongly and negatively related to ADL recovery at discharge than the loss of muscle mass among older patients with aspiration pneumonia. Interventions targeting the intramuscular adipose tissue of the quadriceps may improve ADL among these patients.

Increase in protein intake is related to decreasing intramuscular adipose tissue of the quadriceps in older inpatients: A longitudinal study.

BACKGROUND & AIM: Several randomized controlled trials indicated that an increase in protein intake decreases intramuscular adipose tissue of the thigh in mobility-limited or pre-frail older persons and stroke patients. However, whether the increase in protein intake in older inpatients is related to decreasing intramuscular adipose tissue remains unclear. The aim of this study was to examine the longitudinal relationship between intramuscular adipose tissue of the quadriceps and protein intake in older inpatients. METHODS: This longitudinal study included 193 older inpatients (aged ≥65 years) (median [IQR] age: 83.0 [77.0-88.0]). The primary outcomes were changes in intramuscular adipose tissue of the quadriceps and protein intake. Intramuscular adipose tissue and muscle mass of the quadriceps were examined using ultrasound images (i.e., quadriceps echo intensity and thickness). The changes in quadriceps echo intensity and protein intake were calculated by subtracting the quadriceps echo intensity and protein intake at admission from those values at discharge. Multiple linear regression analysis adjusting for confounding factors was used to determine whether the change in protein intake was independently and significantly related to changes in quadriceps echo intensity and thickness. RESULTS: Quadriceps echo intensity at discharge (81.3 ± 20.6 [a.u.]) was significantly lower than at admission (84.0 ± 20.5 [a.u.]). Protein intake at discharge (1.2 [1.0-1.4] g/kg/day) was significantly higher than at admission (1.2 [0.9-1.4] g/kg/day). Change in protein intake was negatively and significantly related to the change in quadriceps echo intensity. In contrast, change in protein intake was not independently and significantly related to change in quadriceps thickness. CONCLUSIONS: Our results indicate that an increase in protein intake is related to a decrease in intramuscular adipose tissue of the quadriceps in older inpatients. Nutritional intervention for increasing protein intake in older inpatients may be essential for decreasing intramuscular adipose tissue of the quadriceps.

Greater intramuscular adipose tissue of the quadriceps in older inpatients at post-acute hospital admission is more strongly related to a low rate of home discharge than a loss of muscle mass.

This study aimed to examine the relationships between intramuscular adipose tissue and muscle mass of the quadriceps at post-acute hospital admission and the low rate of home discharge. This prospective study included 389 inpatients aged ≥ 65 years. Patients were divided into two groups according to the destination: home discharge (n = 279) and no-home discharge (n = 110) groups. The primary outcome was hospital discharge destination (home discharge or not). Intramuscular adipose tissue and muscle mass of the quadriceps were assessed at post-acute hospital admission using echo intensity and muscle thickness on ultrasound images, respectively. Logistic regression analysis was used for determining whether quadriceps echo intensity is related to home discharge. Quadriceps echo intensity was significantly and independently associated with home discharge (odds ratio [per 1 SD increase] = 1.43, p = 0.045). Quadriceps thickness was not associated with home discharge (odds ratio [per 1 SD increase] = 1.00, p = 0.998). Our study indicates that greater intramuscular adipose tissue of the quadriceps in older inpatients at post-acute hospital admission is more strongly related to a low rate of home discharge than a loss of muscle mass.

Longitudinal relationship between muscle mass and intramuscular adipose tissue of the quadriceps in older inpatients at different activities of daily living levels.

BACKGROUND & AIMS: Whether there is a longitudinal relationship between muscle mass and intramuscular adipose tissue of the quadriceps at different activities of daily living (ADL) levels remains unclear. This study aimed to examine the longitudinal relationship between muscle mass and intramuscular adipose tissue of the quadriceps in older inpatients at different ADL levels. METHODS: This prospective cohort study was hospital-based and included 198 inpatients aged ≥65 years. Ultrasound images were acquired using B-mode ultrasound imaging. Muscle mass and intramuscular adipose tissue of the quadriceps were assessed based on muscle thickness and echo intensity, respectively. The changes in quadriceps thickness and echo intensity were calculated by subtracting these baseline values from these values at discharge. ADL were assessed at admission using the Barthel Index (BI). The participants were divided into the low BI (BI score <60) and high BI (BI score ≥60) groups in accordance with the BI score. Multiple regression analysis was performed to examine whether the change in quadriceps echo intensity was independently and significantly related to change in quadriceps thickness, even after adjusting for confounding factors in the total participants and high and low BI groups. RESULTS: The number of the high and low BI groups were 54 and 144. Change in quadriceps echo intensity was independently and significantly related to changes in quadriceps thickness of the total participants (ß = -0.53, p < 0.01) and low BI (ß = - 0.51, p < 0.01) and high BI (ß = -0.70, p < 0.01) groups. CONCLUSIONS: The results of this study indicate that there is a longitudinal negative relationship between muscle mass and intramuscular adipose tissue of the quadriceps in older inpatients regardless of ADL level. Intramuscular adipose tissue may be an important contributing factor for muscle mass.

The degree of recovery in swallowing ability in older inpatients with aspiration pneumonia is related to intramuscular adipose tissue of the quadriceps than to muscle mass.

BACKGROUND & AIM: A recent study reported that the increase in intramuscular adipose tissue of the quadriceps in older inpatients is related to a decreasing degree of recovery in swallowing ability compared to the loss of muscle mass. However, whether the association remains true in case of aspiration pneumonia is unclear. Therefore, this study aimed to examine the relationship between the degree of recovery in swallowing ability and intramuscular adipose tissue in the quadriceps of older inpatients with aspiration pneumonia. METHODS: This prospective study included 39 older patients with aspiration pneumonia. Swallowing ability was assessed using the Food Intake Level Scale (FILS). The indicators for the degree of recovery in swallowing ability were FILS at discharge and change in FILS. A greater change in FILS indicates a greater improvement in swallowing ability. Intramuscular adipose tissue and muscle mass of the quadriceps were evaluated at admission using echo intensity and muscle thickness on ultrasound images, respectively. Multiple regression analysis was used to determine whether the echo intensity of the quadriceps was independently and significantly related to FILS at discharge and the change in FILS. Independent variables were age, sex, days from disease onset, echo intensity and muscle thickness of the quadriceps, subcutaneous fat thickness of the thigh, FILS at admission, and number of units of rehabilitation therapy. RESULTS: Echo intensity of the quadriceps (ß = -0.363, p = 0.012) and FILS at admission (ß = 0.556, p < 0.001) were independently and significantly associated with FILS at discharge (R2 = 0.760, f2 = 3.167, statistical power = 1.000). Similar variables (echo intensity of the quadriceps [ß = -0.498, p = 0.012] and FILS at admission [ß = -0.635, p < 0.001]) were independently and significantly related to change in FILS (R2 = 0.547, f2 = 1.208, statistical power = 0.998). Quadriceps muscle thickness was not independently and significantly related to FILS at discharge and change in FILS. CONCLUSION: Our results indicate that intramuscular adipose tissue of the quadriceps in older inpatients with aspiration pneumonia is more strongly related to the degree of recovery in swallowing ability (that is, swallowing ability at discharge and change in swallowing ability) than muscle mass, and patients who have high intramuscular adipose tissue of the quadriceps at admission have a lower degree of recovery in swallowing ability.

Increase in muscle mass of the quadriceps is related to decrease in intramuscular adipose tissue in convalescent stroke patients: A longitudinal study.

BACKGROUND & AIMS: A previous study indicated that an increase in muscle mass is related to a decrease in intramuscular adipose tissue in older peoples. However, the longitudinal relationship between muscle mass and intramuscular adipose tissue of stroke patients remains unclear. This study aimed to examine the longitudinal relationships between muscle mass and intramuscular adipose tissue of the quadriceps on the paretic and non-paretic sides in convalescent stroke patients. METHODS: This longitudinal study included 24 convalescent stroke patients. Ultrasound images were acquired at hospital admission and discharge using B-mode ultrasound imaging. Muscle mass and intramuscular adipose tissue of the quadriceps were evaluated with muscle thickness and echo intensity, respectively. Multiple regression analysis was performed to confirm whether changes in echo intensity of the quadriceps on the paretic and non-paretic sides were related to changes in muscle thickness of those. The age, sex, days from onset stroke, change in the subcutaneous fat thickness, and paretic lower extremity function were set as an independent variable. RESULTS: Change in echo intensity of the quadriceps on the paretic side (ß = - 0.55, p = 0.018) was independently and significantly associated with changes in muscle thickness of the quadriceps on the paretic side. Similarly, change in echo intensity of the quadriceps on the non-paretic side (ß = -0.55, p = 0.013) was independently and significantly associated with change in muscle thickness of the quadriceps on the non-paretic side. CONCLUSIONS: Our findings indicate that muscle mass and intramuscular adipose tissue of the quadriceps are strongly and negatively correlated and an increase in muscle mass of the quadriceps is related to a decrease in intramuscular adipose tissue on the paretic and non-paretic sides in convalescent stroke patients. Furthermore, we must recognize that convalescent stroke patients with a decrease in muscle mass have an increase in intramuscular adipose tissue.

Higher malnutrition risk in older inpatients who are referred to the department of rehabilitation is related to increase of intramuscular adipose tissue: A prospective study.

BACKGROUND & AIMS: A recent cross-sectional study reported that a higher intramuscular adipose tissue of the quadriceps is related to higher malnutrition risk in older inpatients. However, a longitudinal relationship between them in older inpatients remains unclear. This study aimed to examine the relationship between the malnutrition risk at hospital admission and change in quadriceps intramuscular adipose tissue induced during the hospital stay in older inpatients. METHODS: The inclusion criteria in this longitudinal study were older patients (aged ≥65 years) who were referred to the department of rehabilitation. Patients who died during a hospital stay, who underwent thigh amputation, and who had a hospital stay of <3 days or a lack of data were excluded from the study. Malnutrition risk at post-acute hospital admission was assessed using Geriatric Nutritional Risk Index (GNRI). Intramuscular adipose tissue and muscle mass of the quadriceps were assessed at hospital admission and discharge using echo intensity and muscle thickness on ultrasound images. The changes in quadriceps echo intensity and thickness were calculated by subtracting these baseline values from these values at discharge. Multiple regression analysis was performed to examine whether GNRI at admission is independently and significantly related to the quadriceps echo intensity and thickness at discharge and changes in quadriceps echo intensity and thickness. The independent variables were GNRI, age, sex, days from onset disease, disease, quadriceps echo intensity or thickness at admission, and change in quadriceps thickness. RESULTS: This study included 200 inpatients (median [interquartile range] age: 83.0 [77.0-88.0], 57.0% female). GNRI at admission was significantly and independently related to quadriceps echo intensity at discharge (ß = -0.136, p = 0.008) and change in quadriceps echo intensity (ß = -0.177, p = 0.008). In contrast, GNRI was not significantly and independently related to quadriceps thickness at discharge (ß = 0.087, p = 0.158) and change in quadriceps thickness (ß = 0.133, p = 0.158). CONCLUSIONS: Our results suggest that a higher malnutrition risk at post-acute hospital admission in older inpatients is related to an increase of intramuscular adipose tissue of the quadriceps during the hospital stay. Malnutrition risk at hospital admission in older inpatients is considered to be a predictor for an increase of intramuscular adipose tissue of the quadriceps during a hospital stay.

Nutritional and swallowing statuses but not intramuscular adipose tissue and muscle mass are related to activities of daily living in older inpatients who are judged as severely low body mass index in the Global Leadership Initiative on Malnutrition criteria.

BACKGROUND & AIMS: Which factors are related to activities of daily living (ADL) in older inpatients who are judged as the severely low body mass index (BMI) in the Global Leadership Initiative on Malnutrition (GLIM) criteria is unclear. This study aimed to examine the related factors to ADL in older inpatients who are judged as severely low BMI in the GLIM criteria. METHODS: This cross-sectional study included 377 inpatients aged ≥70 years. We divided the participants into the following three groups: the severely low BMI group (<17.8 kg/m2) (n = 106), moderately low BMI group (≥17.8 to < 20.0 kg/m2) (n = 87), and normal BMI group (≥20.0 kg/m2) (n = 184). ADL were assessed using the motor-Functional Independence Measure (FIM). Multiple regression analyses were used to identify the factors independently associated with the motor-FIM score in each group. RESULTS: The Food Intake Level Scale (FILS) and Geriatric Nutritional Risk Index (GNRI) were significantly related to the motor-FIM score of the severely low BMI group. The FILS, GNRI, updated Charlson comorbidity index (UCCI), and quadriceps echo intensity were significantly related to the motor-FIM score of the moderately low BMI group. The FILS, GNRI, UCCI, quadriceps thickness, and subcutaneous fat thickness of the thigh were significantly related to the motor-FIM score of the normal BMI group. CONCLUSIONS: Our findings indicate that nutritional and swallowing statuses but not intramuscular adipose tissue and muscle mass are related to ADL in older inpatients who are judged as severely low BMI in the GLIM criteria. Intervention for nutritional and swallowing statuses may be prioritized over an exercise intervention to improve ADL of older inpatients who are judged as severely low BMI.

Extracellular water-to-total body water ratio is an essential confounding factor in bioelectrical impedance analysis for sarcopenia diagnosis in women.

PURPOSE: The extracellular water-to-total body water ratio (ECW/TBW) is used in bioelectrical impedance analysis (BIA) for measuring muscle mass; however, ECW/TBW may be affected by several factors common in older individuals. Here, we assessed the relationships of ECW/TBW with handgrip strength, gait speed, and skeletal muscle mass index (SMI) in older women. METHODS: In this cross-sectional study, 73 community-dwelling women aged ≥ 65 years who could independently perform activities of daily living were included. ECW/TBW was measured using direct segmental multifrequency BIA. The participants were divided into ECW/TBW < 0.40 (n = 54) and ECW/TBW ≥ 0.40 (n = 19) groups, with the latter indicating overhydration. SMI was calculated as appendicular skeletal muscle mass/(height)2 (kg/m2). The relationships of SMI with handgrip strength and gait speed were assessed using partial correlation coefficients. Age, number of medications, pain, and medical history were treated as control variables. RESULTS: The average age of participants was 77.6 ± 6.0 years. The SMI was significantly related to handgrip strength (partial correlation coefficient = 0.293, P = 0.016) but not to gait speed (partial correlation coefficient = - 0.183, P = 0.138). Similarly, the SMI of the ECW/TBW < 0.40 group was significantly related to handgrip strength (partial correlation coefficient = 0.372, P = 0.009) but not gait speed (partial correlation coefficient = - 0.267, P = 0.066); however, the SMI of the ECW/TBW ≥ 0.40 group was not related to either variable. CONCLUSION: ECW/TBW represents a confounding factor, which should be considered when using BIA for sarcopenia diagnosis.

Relationship between muscle mass and fraction of intramuscular adipose tissue of the quadriceps in older inpatients.

BACKGROUND: In 2021, the International Society of Physical and Rehabilitation Medicine (ISPRM) special interest group on sarcopenia included the quadriceps thickness assessed with ultrasound image as an indicator of muscle mass in the diagnosis criteria of sarcopenia. If quadriceps echo intensity of older inpatients is to be a strong predictor of quadriceps thickness, muscle quality of the quadriceps may be estimated by the muscle mass when diagnosing sarcopenia using the criteria of ISPRM. OBJECTIVE: This study aimed to examine the association between muscle mass and fraction of intramuscular adipose tissue of the quadriceps in older inpatients. METHODS: This cross-sectional study included 399 inpatients aged ≥ 65 years. Primary outcomes were muscle mass and fraction of intramuscular adipose tissue of the quadriceps. Images were acquired using a B-mode ultrasound. Muscle mass and fraction of intramuscular adipose tissue of the quadriceps were assessed based on the muscle thickness and echo intensity, respectively. A multiple regression analysis (forced entry method) was performed to confirm whether quadriceps echo intensity was related to quadriceps thickness even after adjusting for other factors. RESULTS: In the multiple regression analyses for both male and female models, quadriceps echo intensity (male: ß = - 0.537, p < 0.001; female: ß = - 0.438, p < 0.001), Geriatric Nutritional Risk Index (male: ß = 0.236, p < 0.001; female: ß = 0.213, p < 0.001), and subcutaneous fat thickness of the thigh (male: ß = 0.197, p < 0.001; female: ß = 0.248, p < 0.001) were independently and significantly associated with quadriceps thickness. CONCLUSIONS: Our results show that there is a negative and significant association between muscle mass and fraction of intramuscular adipose tissue in older inpatients. Muscle quality of the quadriceps in older inpatients may be estimated to some extent by the muscle mass.

Longitudinal relationship between intramuscular adipose tissue of the quadriceps and activities of daily living in older inpatients.

BACKGROUND: The longitudinal relationship between intramuscular adipose tissue of the quadriceps and activities of daily living (ADL) in older inpatients remains unclear. This study aimed to examine whether decrease of intramuscular adipose tissue of the quadriceps in older inpatients is related to the recovery of ADL than increase of muscle mass. METHODS: This longitudinal study included 202 inpatients aged ≥65 years [median age: 83.0 (77.0-88.0), 56.4% female]. Recovery of ADL during hospital stay was assessed using the change in Barthel index (BI) score (i.e. BI score at discharge minus BI score at admission) and BI score at discharge. Intramuscular adipose tissue and muscle mass of the quadriceps were assessed using echo intensity and muscle thickness on ultrasound images, respectively. Higher echo intensity indicates greater intramuscular adipose tissue. Multiple regression analysis was performed to identify the factors independently associated with the change in BI score and BI score at discharge. Changes in quadriceps echo intensity and thickness and subcutaneous fat thickness of the thigh, quadriceps echo intensity and thickness, and subcutaneous fat thickness of the thigh at admission, age, sex, days from onset disease, BI score at admission, and disease were set as independent variables. RESULTS: The means of the change in quadriceps echo intensity and thickness were -2.3 ± 15.7 and 0.1 ± 0.4 cm, respectively. The median of the change in BI score was 15.0 (0.0-30.0). The quadriceps echo intensity at discharge was significantly lower than at admission (P = 0.043). The quadriceps thickness (P = 0.004) and BI score at discharge (P < 0.001) were significantly higher than those at admission. Change in quadriceps echo intensity was independently and significantly associated with the change in BI score (ß = -0.25, P = 0.006) and BI score at discharge (ß = -0.18, P = 0.006). In contrast, change in quadriceps thickness was not independently and significantly associated with the change in BI score (ß = 0.09, P = 0.244) and BI score at discharge (ß = 0.06, P = 0.244). CONCLUSIONS: Our study indicates that a decrease of intramuscular adipose tissue of the quadriceps is related to the recovery of ADL than an increase of muscle mass in older inpatients. Intramuscular adipose tissue of the quadriceps in older inpatients is considered to be a predictor for the recovery of ADL, and intervening for intramuscular adipose tissue may be important for improving ADL in older inpatients.

Intramuscular adipose tissue of the quadriceps is more strongly related to recovery of swallowing ability than is muscle mass in older inpatients: A prospective study.

OBJECTIVES: This study aimed to examine whether intramuscular adipose tissue of the quadriceps at admission is related to the recovery of swallowing ability during a hospital stay in older inpatients. METHODS: This prospective study included 344 inpatients ages ≥ 65 y. Those who had stroke that was the obvious cause of dysphagia were excluded. Recovery of swallowing ability was assessed using Food Intake Level Scale (FILS) score at discharge and FILS change. Ultrasound images were acquired at admission. Intramuscular adipose tissue and muscle mass of the quadriceps were assessed based on echo intensity and muscle thickness, respectively. Multiple regression analysis was performed to examine whether quadriceps echo intensity is independently associated with FILS score at discharge and FILS change. The independent variables were quadriceps echo intensity and thickness, subcutaneous fat thickness of the thigh, Barthel Index score at admission, age, sex, number of medications, C-reactive protein, updated Charlson Comorbidity Index, FILS score at admission, Geriatric Nutritional Risk Index, days from disease onset, length of hospital stay, and units of rehabilitation therapy. RESULTS: Quadriceps echo intensity was independently and significantly associated with FILS score at discharge (ß = -0.15, P < 0.01) and FILS change (ß = -0.19, P < 0.01). Quadriceps thickness was not independently and significantly associated with FILS score at discharge or FILS change. CONCLUSIONS: The present study revealed that intramuscular adipose tissue of the quadriceps in older inpatients is more strongly related to recovery of swallowing ability than is muscle mass.

Intramuscular adipose tissue in the quadriceps is more strongly related to recovery of activities of daily living than muscle mass in older inpatients.

BACKGROUND: The relationship between intramuscular adipose tissue at admission and recovery of activities of daily living (ADL) remains unclear. This study aimed to examine the relationship between intramuscular adipose tissue in the quadriceps at admission and recovery of ADL in older inpatients. METHODS: This prospective study included 404 inpatients aged ≥65 years (54.7% female). Recovery of ADL during hospital stay was assessed using the Barthel Index (BI) score at discharge, BI score change, and BI efficiency. Higher BI at discharge, BI score change, and BI efficiency indicate more improvement in ADL. Intramuscular adipose tissue and muscle mass of the quadriceps were assessed using echo intensity and muscle thickness on ultrasound images, respectively. Multiple regression analysis was performed to identify factors independently associated with BI score at discharge, BI score change, and BI efficiency. The independent variables were BI score at admission, echo intensity and muscle thickness of the quadriceps, age, sex, number of medications, C-reactive protein concentration, updated Charlson Comorbidity Index score, Food Intake Level Scale, Geriatric Nutritional Risk Index score, days from onset disease, length of hospital stay, number of units of rehabilitation therapy, and subcutaneous fat thickness of the thigh. RESULTS: The medians (inter-quartile range) of the BI score at discharge, BI score change, and BI efficiency were 60.0 (35.0-80.0), 10.0 (0.0-25.0), and 0.11 (0.00-0.37), respectively. The median (inter-quartile range) of the length of hospital stay (days) and days from onset disease were 58.0 (39.0-92.0) and 79.0 (49.0-112.0), respectively. Quadriceps echo intensity was independently and significantly associated with the BI score at discharge (ß = -0.13, P < 0.01), BI score change (ß = -0.23, P < 0.01), and BI efficiency (ß = -0.21, P < 0.01). Quadriceps thickness was not independently and significantly associated with the BI score at discharge (ß = -0.02, P = 0.68), BI score change (ß = -0.02, P = 0.79), and BI efficiency (ß = 0.03, P = 0.67). CONCLUSIONS: Our study indicates that greater intramuscular adipose tissue in the quadriceps at admission is more strongly related to worse recovery of ADL than less muscle mass in older inpatients. Greater intramuscular adipose tissue in the quadriceps in older inpatients is considered to be a predictor of worse recovery of ADL, and intervening for greater intramuscular adipose tissue may be important for improving ADL in older inpatients.

Greater Quadriceps Muscle Mass at Post-Acute Care Admission is Associated with Better Swallowing Ability at Discharge among Adults with Stroke.

OBJECTIVES: This study aimed to examine the relationship between muscle mass and intramuscular adipose tissue of the quadriceps at post-acute care admission and recovery of swallowing ability in patients with stroke. DESIGN: Prospective study. SETTING AND PARTICIPANTS: This study was hospital-based and included 62 inpatients with stroke. METHODS: The primary outcome was swallowing ability at discharge. The swallowing ability was assessed using the Food Intake Level Scale (FILS). The FILS change was calculated by subtracting FILS at admission from FILS at discharge. Ultrasound images were acquired at admission using B-mode ultrasound imaging. Muscle mass and intramuscular adipose tissue of the quadriceps were assessed based on muscle thickness and echo intensity, respectively. The mean muscle thickness and echo intensity of the right and left quadriceps were used in the analysis. A multiple regression analysis was performed to identify the factors independently associated with the FILS at discharge and FILS change. The independent variables were the muscle thickness and echo intensity of the quadriceps, FILS at admission, age, sex, body mass index, days from stroke onset, C-reactive protein, updated Charlson comorbidity index, number of medications, unit number of rehabilitation therapy, and Barthel Index score at admission. RESULTS: Muscle thickness of the quadriceps was significantly and independently associated with FILS at discharge (ß = 0.27) and FILS change (ß = 0.40). Echo intensity of the quadriceps was not significantly and independently associated with FILS at discharge (ß = 0.22) and FILS change (ß = 0.31). CONCLUSIONS AND IMPLICATIONS: Our results indicated that greater quadriceps muscle mass at post-acute care admission was associated with better swallowing ability at discharge in patients with stroke. Assessing muscle mass of the quadriceps at admission is important for predicting recovery of swallowing ability and interventions for quadriceps muscle mass may be effective for improving swallowing ability of patients with stroke.

Increased intramuscular adipose tissue of the quadriceps is related to decreased activities of daily living in patients who have had a stroke.

OBJECTIVE: This study examined the relationships between intramuscular adipose tissue of the quadriceps on the paretic and non-paretic sides at admission and activities of daily living (ADL) at discharge in patients who had a stroke. METHODS: This prospective cohort study included 44 stroke inpatients. ADL were assessed at discharge using the Barthel index (BI) score. Ultrasound images were acquired at admission using B-mode ultrasound imaging. Intramuscular adipose tissue and muscle mass of the quadriceps were assessed based on echo intensity and muscle thickness, respectively. Relationships between BI score at discharge and quadriceps echo intensity or thickness on the paretic and non-paretic sides were assessed using partial correlation coefficients. Age, sex, days from onset of stroke, Fugl-Meyer assessment lower extremity score, and subcutaneous fat thickness of the thigh were used as the control variables in the partial correlation analysis. RESULTS: BI score at discharge was significantly related to quadriceps echo intensity on the paretic (partial correlation coefficient = -0.377, P = 0.018) and non-paretic (partial correlation coefficient = -0.364, P = 0.023) sides. By contrast, quadriceps thickness on the paretic (partial correlation coefficient = 0.284, P = 0.075) and non-paretic (partial correlation coefficient = 0.278, P = 0.083) sides were not significantly related to BI score at discharge. CONCLUSIONS: The present study revealed the negative relationship between intramuscular adipose tissue of the quadriceps on the paretic and non-paretic sides at admission and ADL at discharge. Assessments and interventions of intramuscular adipose tissue in the quadriceps may be essential for predicting and improving ADL of patients who have had a stroke.

Increased total body extracellular-to-intracellular water ratio in community-dwelling elderly women is associated with decreased handgrip strength and gait speed.

OBJECTIVE: As the extracellular-to-intracellular water (ECW/ICW) ratio of the thigh is negatively associated with knee extension strength or gait speed in the elderly, an increase in the total body ECW/ICW ratio in the elderly is considered to be related to a decrease in physical function. However, these relationships have not been properly investigated. The aim of this study was to investigate the relationship of handgrip strength and gait speed with the total body ECW/ICW ratio in community-dwelling elderly women. METHODS: The present study used a cross-sectional design. We enrolled 71 community-dwelling women, ≥65 y of age, who could independently perform activities of daily living. The total body ECW/ICW ratio was measured using bioelectrical impedance analysis. Relationships between the total body ECW/ICW ratio and grip strength and gait speed were assessed using Pearson's correlation coefficient. Additionally, stepwise multiple regression analysis was used to identify the factors that were independently associated with handgrip strength and gait speed. The independent variables considered were the total body ECW/ICW ratio, age, body mass index, number of medications, presence of pain, and a history of certain conditions. RESULTS: The results indicated that an increased total body ECW/ICW ratio in community-dwelling elderly women was associated with a decreased handgrip strength and gait speed. Furthermore, the total body ECW/ICW ratio was significantly, independently associated with handgrip strength even after adjusting for confounding factors. CONCLUSION: These findings suggest that the total body ECW/ICW ratio may indicate health conditions in community-dwelling elderly women.

Relationship Between Aging and Intramuscular Adipose Tissue in Older Inpatients.

OBJECTIVE: Although older inpatients are known to develop various conditions, whether aging affects intramuscular adipose tissue in older inpatients remains unclear. In particular, an increase in intramuscular adipose tissue in persons aged ≥85 years has previously not been revealed in either older inpatients or community-dwelling older individuals. This study therefore aimed to examine whether aging affects intramuscular adipose tissue in older inpatients. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: This study was clinical-based and included 404 inpatients aged ≥65 years. METHODS: We divided the participants into the following age groups: 65-74 years (n = 63), 75-84 years (n = 171), and ≥85 years (n = 170). B-mode ultrasound imaging was performed, and the intramuscular adipose tissue of the quadriceps was assessed based on echo intensity. One-way analysis of variance and analysis of covariance were used to compare the echo intensity of the quadriceps between the 65-74-year, 75-84-year, and ≥85-year groups. RESULTS: The median (25th-75th percentile) ages of the 65-74-year group, 75-84-year group, and ≥85-year group were 70.0 (68.0-73.0), 80.0 (77.0-82.0), and 89.0 (87.0-91.0), respectively. In the one-way analysis of variance, the quadriceps echo intensity of the ≥85-year group was significantly higher than that of the 65-74-year and 75-84-year groups. In addition, the ≥85-year group had significantly higher quadriceps echo intensity than the 65-74-year group, even after adjusting for other confounding factors. CONCLUSIONS AND IMPLICATIONS: The current study revealed that intramuscular adipose tissue in older inpatients increases with age, and the levels of intramuscular adipose tissue of older inpatients aged ≥85 years is higher than those of older inpatients aged 65-74 years.

Action observation treatment improves gait ability in subacute to convalescent stroke patients.

The aim of this study was to investigate the effects of action observation treatment (AOT) on gait ability in patients with subacute to convalescent stroke. Sixteen patients with subacute stroke were divided into a control group (n = 8) and AOT group (n = 8) when admitted to the convalescent ward. The control group received a conventional rehabilitation only. In addition to conventional rehabilitation, the AOT received AOT for 3 months (30 min per day 5 times per week). The AOT involved observing the action of another subject in a comfortable gait situation from the front, sides, and back via video and conducting the actual action. All participants were assessed during the main-assessment period, which included a baseline (i.e., when admitted to the convalescent ward) and 1, 2, and 3 months after baseline. The sub-assessment period at 2 and 3 months after baseline was conducted with participants who could walk independently. The main outcomes of the main-assessment and sub-assessment periods were Functional Ambulation Classification (FAC) and the 10-m walk test (10MWT), respectively. With respect to the FAC, we used a split plot design analysis of covariance to test the interaction between assessment time and group. There was no significant interaction between assessment time and group in FAC. However, a significant improvement of the 10MWT in the sub-assessment period was observed in the AOT group, but not the control group. Our results indicate that AOT may be an effective therapy for patients with subacute to convalescent stroke who can walk independently.