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.

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.

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.

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.

Changes in Quadriceps Thickness and Echo Intensity in Chronic Stroke Survivors: A 3-Year Longitudinal Study.

OBJECTIVES: The aim of the current study was to examine longitudinal changes in quadriceps muscle mass and intramuscular adipose tissue in chronic stroke survivors. MATERIALS AND METHODS: In this longitudinal study included 34 chronic stroke survivors who lived in the community. Ultimately, 20 chronic stroke survivors received an after 3-year assessment. Fourteen chronic stroke survivors were lost at follow-up. Chronic stroke survivors who were followed and not followed during 3 years were categorized as follow-up group and lost follow-up group, respectively. The quadriceps muscle mass and intramuscular adipose tissue were assessed at baseline and after 3-year assessments based on muscle thickness and echo intensity in ultrasound images, respectively. RESULTS: No significant differences in any characteristics were observed between the flow-up and lost follow-up groups. In the follow-up group, there was a significant decrease in quadriceps thickness on the paretic (10.3% decrease) and non-paretic (17.0% decrease) sides at follow-up after 3 years compared with baseline. There was a significant increase in quadriceps echo intensity on the paretic (20.0% increase) and non-paretic (24.9% increase) sides at follow-up after 3 years compared with baseline. There were significant positive relationships between changes in body weight and changes in quadriceps thickness on the paretic and non-paretic sides. Chronic stroke survivors with greater reductions in body weight showed a trend towards a greater decrease in quadriceps thickness on the paretic and non-paretic sides. CONCLUSIONS: The current results suggest marked longitudinal changes in the skeletal muscles in chronic stroke survivors. Preventing secondary changes in skeletal muscles and limiting decreases in body weight are essential for improving outcomes in chronic stroke survivors.

Increased intramuscular adipose tissue of the quadriceps is more strongly related to declines in ADL than is loss of muscle mass in older inpatients.

BACKGROUND & AIMS: Recent studies have shown that increased intramuscular adipose tissue of the quadriceps in older people is more strongly related to decreased muscle strength, sit-up and sit-down ability, and gait ability than is loss of muscle mass. However, whether increased intramuscular adipose tissue of the quadriceps is more strongly related to declines in activities of daily living (ADL) than is loss of muscle mass in older inpatients remains unclear. This study was performed to examine the relationships of intramuscular adipose tissue and muscle mass of the quadriceps with ADL in older inpatients. METHODS: This cross-sectional study included 371 inpatients aged ≥65 years. The primary outcomes were ADL and intramuscular adipose tissue of the quadriceps. ADL were assessed using the motor-Functional Independence Measure (FIM). Ultrasound images were acquired using B-mode ultrasound imaging. Intramuscular adipose tissue and muscle mass of the quadriceps were assessed based on echo intensity and muscle thickness, respectively. A stepwise multiple regression analysis was performed to identify factors independently associated with the motor-FIM score. The independent variables were the echo intensity and muscle thickness of the quadriceps, age, sex, length of hospital stay, Food Intake Level Scale (FILS), Geriatric Nutritional Risk Index (GNRI) score, C-reactive protein (CRP) concentration, updated Charlson comorbidity index (UCCI), number of medications, and subcutaneous fat thickness of the thigh. RESULTS: Quadriceps echo intensity (ß = - 0.17), FILS (ß = 0.38), GNRI score (ß = 0.24), UCCI (ß = - 0.16), subcutaneous fat thickness of the thigh (ß = - 0.11), and length of hospital stay (ß = 0.09) were independently and significantly associated with the motor-FIM score. Quadriceps thickness (ß = 0.10), age (ß = - 0.07), sex (ß = - 0.04), CRP concentration (ß = - 0.04), and number of medications (ß = 0.03) were not associated with the motor-FIM score. CONCLUSIONS: Increased intramuscular adipose tissue of the quadriceps is more strongly related to declines in ADL than is loss of muscle mass. Randomized controlled trials are needed to determine whether decreasing intramuscular adipose tissue of the quadriceps in older inpatients leads to improvement of ADL.

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.

Using GLIM criteria, cutoff value for low BMI in Asian populations discriminates high or low muscle mass: A cross-sectional study.

OBJECTIVES: The aim of this study was to examine whether differences in muscle mass and intramuscular adipose tissue are present between patients with a moderately and severely low body mass index (BMI) as discriminated by the cutoff value for a low BMI among patients ≥70 y of age in Asian populations according to the Global Leadership Initiative on Malnutrition (GLIM) criteria. METHODS: This cross-sectional study included 345 inpatients ≥70 y of age. The participants were placed into one of the following three groups: severely low BMI (<17.8 kg/m2; n = 96), moderately low BMI (≥17.8 to <20 kg/m2; n = 81), and normal BMI (≥20 kg/m2; n = 168). Ultrasound images were obtained with B-mode ultrasound imaging. Muscle mass and intramuscular adipose tissue of the quadriceps were assessed based on the muscle thickness and echo intensity, respectively. Analysis of covariance was used to examine the differences in the quadriceps thickness and echo intensity among the three groups. RESULTS: The quadriceps thickness and echo intensity in the severely low, moderately low, and normal BMI groups were 0.9 ± 0.3, 1.1 ± 0.4, and 1.4 ± 0.5 cm and 93.3 ± 20.8, 91.3 ± 19.3, 80.1 ± 21.6, respectively. The quadriceps thickness in the severely low BMI group was statistically significantly lower than that in the moderately low BMI (P < 0.001) and normal BMI (P < 0.001) groups, and the quadriceps thickness in the moderately low BMI group was also statistically significantly lower than that in the normal BMI group (P < 0.001). The quadriceps echo intensity showed no significant differences among the three groups. CONCLUSIONS: The cutoff value for a low BMI discriminates high or low muscle mass. Results of this study supported the validity of 17.8 kg/m2 as the cutoff value for a low BMI with which to grade the severity of malnutrition in Asian populations ≥70 y of age according to the GLIM criteria from the perspective of muscle mass.

Quantitative features of intramuscular adipose tissue of the quadriceps and their association with gait independence in older inpatients: A cross-sectional study.

OBJECTIVE: The aim of this study was to examine the quantitative features of intramuscular adipose tissue of the quadriceps and their association with gait independence in older inpatients. METHODS: This was a cross-sectional study with 216 inpatients ≥65 y of age. We also recruited 40 community-dwelling healthy individuals in the same age group who were able to walk independently for matched-pair analysis to determine the quantitative features of intramuscular adipose tissue in older inpatients. Participants were assigned to total assistance (Functional Independence Measure [FIM] gait score 1 or 2), partial assistance (FIM gait score 3-5), and independent (FIM gait score 6 or 7) groups. Ultrasound images were acquired using B-mode ultrasound imaging. Intramuscular adipose tissue and muscle mass of the quadriceps were assessed based on echo intensity and muscle thickness, respectively. RESULTS: Echo intensity of the quadriceps of older inpatients was increased to ~1.66 times that of matched healthy older people. Echo intensity of the independent group was significantly lower than that of the total and partial assistance groups. No differences were found in quadricep thickness among the three groups. CONCLUSIONS: The results from the present study suggested that intramuscular adipose tissue of the quadriceps of older inpatients was increased to ~1.7 times that of healthy older individuals matched for demographic characteristics. More intramuscular adipose tissue of the quadriceps was observed among older inpatients who were unable to walk independently compared with older inpatients who were able to walk independently.

Effects of long-term self-massage at the musculotendinous junction on hamstring extensibility, stiffness, stretch tolerance, and structural indices: A randomized controlled trial.

OBJECTIVES: The purpose of this study was to examine the effect of long-term self-massage at the musculotendinous junction on hamstring extensibility, stiffness, stretch tolerance, and structural indices. DESIGN: Single-blind, randomized, controlled trial. SETTING: Laboratory. PARTICIPANTS: Thirty-seven healthy men. INTERVENTION: The right or left leg of each participant was randomly assigned to the massage group, and the other leg was assigned to the control group. The participants conducted self-massage at the musculotendinous junction for 3 min daily, five times per week, for 12 weeks. MAIN OUTCOME MEASURES: Hamstring extensibility, stiffness, stretch tolerance, and structural indices were measured by a blinded examiner prior to the massage intervention and after 6 and 12 weeks of intervention. RESULTS: The maximum hip flexion angle (HFA) and the maximum passive pressure after 6 and 12 weeks of intervention in the massage group were significantly higher than prior to intervention. The visual analog scale (for pain perception) at maximum HFA, the stiffness of the hamstring, and the structural indices did not differ in either group over the 12 week period. CONCLUSIONS: Our results suggest that long-term self-massage at the musculotendinous junction increases hamstring extensibility by improving stretch tolerance. However, this intervention does not change hamstring stiffness. CLINICAL TRIAL REGISTRATION NUMBER: University Hospital Medical Information Network registration number UMIN000011233.