Age-related changes in muscle thickness and echo intensity of trunk muscles in healthy women: comparison of 20–60s age groups

Dietary factors may be associated with measures of ultrasound-derived skeletal muscle echo intensity

Skeletal muscle echo intensity (EI) is affected by ageing and physical activity; however, the effects of nutrition are less understood. The aim of this study was to explore whether habitual nutrient intake may be associated with ultrasound-derived EI. Partial least squares regression (PLSR) models were trained on an initial sample (n = 100, M = 45; F = 55; 38 ± 15 years) to predict EI of two quadriceps muscles from 19 variables, using the "jack-knife" function within the "pls" package (RStudio), which was then tested in an additional dataset (n = 30, M = 13; F = 17; 38 ± 16 years). EI was determined using B-mode ultrasonography of the rectus femoris (RF) and vastus lateralis (VL) and nutritional intake determined via 3-day weighed food diaries. Mean daily intake of specific nutrients were included as predictor variables with age, sex, and self-reported physical activity. PLSR training model 1 explained ∼52% and model 2 ∼46% of the variance in RF and VL EI, respectively. Model 1 also explained ∼35% and model 2 ∼30% of the variance in RF and VL EI in the additional testing dataset. Age and biological sex were associated with EI in both models (P < 0.025). Dietary protein (RF: β = -7.617, VL: β = -7.480), and selenium (RF: β = -7.144, VL: β = -4.775) were associated with EI in both muscles (P < 0.05), whereas fibre intake (RF: β = -5.215) was associated with RF EI only and omega-3 fatty acids (n-3/ω-3 FAs, RF: β = 3.145) with VL EI only (P < 0.05). Therefore, absolute protein, selenium, fibre, and n-3 FAs may be associated with skeletal muscle EI, although further mechanistic work is required before claiming causal inference.

Comparison of the masses and amounts of intramuscular non-contractile tissue of the lower extremity muscles, mobility and balance ability, and cognitive function between older adults with and without low back pain: A pilot study

INTRODUCTION

This study compared the masses and amounts of intramuscular non-contractile tissue of multiple lower extremity muscles measured using an ultrasound imaging device, as well as the mobility and balance ability and cognitive function between community-dwelling older adults with and without low back pain (LBP).

METHODS

Twenty-five community-dwelling older adults were classified into control (CTR) (n = 17, asymptomatic) and LBP (n = 8) groups. The current LBP status in the LBP group was as follows: duration period: 99.4 ± 81.3 months, Numerical Rating Scale: 4.8 ± 0.9, and Oswestry Disability Index: 15.3 ± 10.4%. The thicknesses and the echo intensities of various muscles (gluteus maximus, medius, and minimus; rectus femoris; vastus intermedius and lateralis; long and short heads of the biceps femoris; semitendinosus; semimembranosus; tibialis anterior; medial head of the gastrocnemius; soleus; and tibialis posterior) were measured using an ultrasound imaging device. Mobility and balance ability were assessed by measuring the usual and maximal walking speeds, timed up-and-go time, five-chair-stand time, and one-legged stance time. Mini-Mental State Examination scores were also assessed.

RESULTS

The gluteus medius muscle thickness was significantly lower in the LBP group than in the CTR group. The thicknesses and echo intensities of the other lower extremity muscles did not differ significantly between the CTR and LBP groups. The usual walking speed was also significantly slower in the LBP group than in the CTR group. Balance ability and cognitive function did not differ significantly between the two groups.

CONCLUSION

The results of the present study demonstrated lower gluteus medius muscle mass and slower usual walking speed in community-dwelling older adults with LBP compared to those in older adults without LBP; however, other variables did not differ significantly between these groups.

Sex differences in the association between the muscle quality index and the incidence of depression: A cross-sectional study

BACKGROUND

Depression presents significant challenges to mental health care. Although physical activity is highly beneficial to mental and physical health, relatively few studies have conducted on the relationship between them.

AIM

To investigate the association between muscle quality index (MQI) and incidence of depression.

METHODS

The data used in this cross-sectional study were obtained from the 2011-2014 National Health and Nutritional Examination Survey, which included information on MQI, depression, and confounding factors. Multivariable logistic regression models were employed, while taking into account the complex multi-stage sampling design. A restricted cubic spline model was utilized to investigate the non-linear relationship between the MQI and depression. Additionally, subgroup analyses were performed to identify influential factors.

RESULTS

The prevalence of depression in this population was 8.44%. With the adjusted model, the MQI was associated with depression in females (odds ratio = 0.68, 95% confidence interval: 0.49-0.95) but not in males (odds ratio = 1.08, 95% confidence interval: 0.77-1.52). Restricted cubic spline adjustment of all covariates showed a significant negative non-linear relationship between depression and the MQI in females. The observed trend indicated an 80% decrease in the risk of depression for each unit increase in MQI, until a value of 2.2. Subsequently, when the MQI exceeded 2.2, the prevalence of depression increased by 20% for every unit increase in the MQI. Subgroup analyses further confirmed that the MQI was negatively associated with depression.

CONCLUSION

The MQI was inversely correlated with depression in females but not males, suggesting that females with a higher MQI might decrease the risk of depression.

Intramuscular fat infiltration influences mechanical properties during muscle contraction in older women

Although evidence suggests that intramuscular fat infiltration may influence muscle strength, the precise mechanisms remain unclear. This study aimed to determine whether intramuscular fat infiltration affects muscle mechanical properties during contraction and whether these mechanical properties mediate the relationship between intramuscular fat infiltration and muscle strength. Seventy-nine healthy older women aged 75.1 ± 6.8 years were included in this study. The echo intensity (EI) of the vastus lateralis (VL) was measured as an intramuscular fat infiltration index using B-mode ultrasonography. Maximum voluntary isometric contraction strength (MVIC) was assessed using a dynamometer. The VL shear elastic modulus (G), a mechanical property index, was measured using ultrasound shear wave elastography under various muscle contraction conditions, at rest and at 15%, 30%, and 45% MVIC (G0, G15, G30, and G45). To evaluate the degree of increase in the shear elastic modulus with increasing muscle contraction intensity, the slope of the regression line (Gslope) between muscle contraction and shear elastic modulus was calculated for each participant. The results showed that EI was significantly associated with G30 and G45 but not with G0 or G15. The EI can significantly explain the inter-individual differences in Gslope. Mediation analysis revealed that the effect of EI on MVIC through Gslope was significant (indirect effect = -0.31, 95% confidence interval (-0.57, -0.12)). These findings suggest that a greater EI is associated with a lower G during muscle contraction. Furthermore, our results show that the relationship between EI and MVIC is mediated by Gslope.

Ex-vivo validation of spatial gain sonography for the quantification of echo intensity in fascicle-aligned ultrasound images in ten anatomical muscles in Bos taurus

This study aimed to validate the concept of spatial gain sonography for quantifying texture-related echo intensity in B-mode ultrasound of skeletal muscle. Fifty-one bovine muscles were scanned postmortem using B-mode ultrasonography at varying fascicle probe angles (FPA). The relationship between mean gray values (MGV) and FPA was fitted with a sinusoidal and a linear function, the slope of which was defined as tilt echo gain (TEG). Macroscopic muscle cross sections were optically analyzed for intramuscular connective tissue (IMCT) content which was plotted against MGV at 0° FPA (MGV_00). MGV peaked at FPA 0°. Sine fits were superior to linear fits (adjusted r2-values 0.647 vs. 0.613), especially for larger FPAs. In mixed models, the pennation angle was related to TEG (P < 0.001) and MGV_00 (P = 0.035). Age was relevant for MGV_00 (P < 0.001), but not TEG (P > 0.10). The correlation between the IMCT percentage and MGV_00 was significant but weak (P = 0.026; adjusted r2 = 0.103). The relationship between fascicle probe angle and echo intensity in B-mode ultrasound can be modeled more accurately with a sinusoidal but more practically for clinical use with a linear fit. The peak mean gray value MGV_00 can be used to compare echo intensity across muscles without the bias of pennation angle.

Diagnostic Accuracy of the Short Physical Performance Battery in Detecting Frailty and Prefrailty in Community-Dwelling Older Adults: Results From the PRO-EVA Study

BACKGROUND AND PURPOSE

The Short Physical Performance Battery (SPPB) is widely used for older adults since it has a high level of validity, reliability, and responsiveness in measuring function in this population. However, only a few studies of diagnostic accuracy have assessed SPPB capacity in detecting frailty and prefrailty by estimating more detailed measurement properties. Thus, the present study aimed to evaluate the SPPB's diagnostic accuracy in detecting frailty and prefrailty, in addition to identifying cut-off points for walking time and chair stand time.

METHODS

This is a cross-sectional study composed of 786 community-dwelling older adults 60 years or older, in which sociodemographic and anthropometric data, frailty phenotype, and total SPPB score, as well as walking time and chair stand time, were assessed. Analysis of a receiver operating characteristic curve was performed to identify the cut-off point, sensitivity, and specificity in the total SPPB score, as well as the walking time and chair stand time for frailty and prefrailty screening. Accuracy and positive and negative predictive values were subsequently calculated.

RESULTS AND DISCUSSION

The cut-off points identified for the total SPPB score, walking time, and chair stand time were 9 points or less (accuracy of 72.6%), 5 seconds or less, and 13 seconds or less, respectively, for frailty screening and 11 points or less (accuracy of 58.7%), 4 seconds or less, and 10 seconds or less, respectively, for prefrailty screening. The walking time showed greater frailty discriminatory capacity compared with the chair stand time (effect size = 1.24 vs 0.64; sensitivity = 69% vs 59%; and specificity = 84% vs 75%).

CONCLUSIONS

The total SPPB score has good diagnostic accuracy to discriminate between nonfrail and frail older adults using a cut-off point of 9 or less, being better to identify the true negatives (older adults who are not frail). Although the SPPB's diagnostic accuracy measures for detecting prefrailty were low to moderate, this instrument can help in screening prefrail older adults from the cutoff point of 11 or less in the total SPPB score. Identification of prefrail older adults enables implementing early treatment in this target audience and can prevent their advance to frailty.

The effects of Pilates training on abdominal muscle thickness and core endurance in patients with Parkinson's disease: a single-blind controlled clinical study

BACKGROUND

This study aims at examining the effects of Pilates training on the transversus abdominis (TrA) and internal obliques (IO) muscle thickness and core endurance in different positions in patients with Parkinson's Disease.

METHODS

Patients were divided into 2 groups as Pilates training (n = 13) and control (n = 10) groups. Pilates training was performed twice a week for 6 weeks. The participants' muscle thickness and core endurance were measured at the beginning of the study (pretraining), and the effectiveness of Pilates training was then assessed in the 6th week (posttraining) and in the 12th-week follow-up. The thickness of the TrA and IO muscles was measured with a two-dimensional ultrasonography device. Core endurance was assessed with prone bridge and sit-ups tests.

RESULTS

The assessments of the Pilates training group after the 6-week showed a statistically significant increase in the prone bridge and sit-ups test performances, and an increase in the thickness of the IO muscle [during resting in the supine position and abdominal drawing-in maneuver (ADIM) in standing position] and the TrA muscle (during ADIM in the standing position) (p < 0.05). Pilates exercises were also shown to have improved core muscle endurance and thickness (IO thickness during ADIM in the standing position and TrA thickness during resting in the supine position, ADIM in the supine and standing position) in the Pilates training group after a period of 18 weeks (p < 0.05).

DISCUSSION

Pilates training has a favorable effect on the core endurance, and the TrA and IO muscle thickness of patients with Parkinson's disease and this effect can be maintained until three months after the training.

Effect of age on shear modulus, muscle thickness, echo intensity of the upper limb, lower limb, and trunk muscles in healthy women

PURPOSE

This study aimed to examine the effect of age on the mechanical properties, muscle size, and muscle quality in the upper and lower limb and trunk muscles.

METHODS

We evaluated the shear modulus (G), muscle thickness (MT), and echo intensity (EI) of the upper and lower limb and trunk muscles of 83 healthy women (21-83-year-old). The G values of some limb muscles were measured in relaxed and stretched positions.

RESULTS

Regarding the effect of age on G at the distinct positions, the G of the upper limb muscles were not significantly correlated with age in the relaxed and stretched positions. In contrast, the G of the iliacus showed a significant negative correlation in both positions. Additionally, the G of the rectus femoris had a significant negative correlation only in the relaxed position. Regarding differences among body parts, the G of the lower limb and oblique abdominal muscles showed a significant negative correlation, but no correlation in the upper limb, rectus abdominis, and back muscles. Moreover, MT showed a significant negative correlation with age in the lower limb, abdominal, and erector spinae muscles, but no correlation was detected in the upper limb and lumbar multifidus muscles. EI had a significant positive correlation in all the muscles.

CONCLUSION

The effect of age on G depended on body parts, and the G of the lower limb and oblique abdominal muscles negatively associated with age. Additionally, G in the relaxed position may be more susceptible to aging than G in the stretched position.

Impact of sex and aging on radiographic and functional parameters of the anal sphincter complex in patients with accidental bowel leakage

AIMS

Treatment outcomes for accidental bowel leakage (ABL) may be influenced by age-related sarcopenia. We sought to determine if thickness of the anal sphincter complex on endoanal ultrasound correlated with function in women and men with ABL and if women demonstrated age-related anal sphincter thinning.

METHODS

Consecutive patients with ABL presenting to our pelvic floor clinic from 2012 to 2017 were included. Clinical data were obtained from medical records. External anal sphincter (EAS), imaged by endoanal ultrasound at proximal, mid and distal locations, and IAS thickness were measured at 12, 3, 6, and 9 o'clock; puborectalis muscle (PRM) was measured at 4, 6, and 8 o'clock; and averaged. Anorectal manometry was conducted when clinically indicated. Data were compared using Mann-Whitney tests and linear regression. Results are reported as mean ± SD or median (IQR).

RESULTS

Women (n = 136) were younger than men (n = 26) (61 ± 13 vs. 67 ± 13 years, p = 0.02). More women than men had pelvic surgery and less had colorectal surgery, spinal disorders, or a history of smoking (p < 0.05). Eighty-two percentage of women had an anal sphincter defect versus 31% of men (p < 0.01). All anal sphincter complex components were thinner in women than men with lower squeeze and resting pressures (p < 0.03), even in nulliparous women. Mean resting pressure was lower in older 6.1 (4.6-7.8) versus younger women 8.3 (5.0-12.9) mmHg, p = 0.04.

CONCLUSIONS

Women, even nulliparous, with ABL demonstrate thinner and weaker anal sphincters than men, Aging correlated with an increase in anal sphincter thickness, suggesting that age-related changes in the intrinsic components of the anal sphincter complex associated with ABL are complex and are not always well demonstrated on endoanal ultrasound.

Preliminary Study: Short-term Beneficial Effects of Thai Tok Sen Massage on Pain, Pressure Pain Threshold, and Upper Trapezius Muscle Thickness Among People with Shoulder Pain

Background

Shoulder muscle pain and spasm is the most common problem in people after prolonged working, similar to that resulting from office syndrome. Various medicinal treatments with analgesic drugs, hot packs, therapeutic ultrasound, or deep friction techniques can be clinically applied. Alternatively, traditional Thai massage (TM) with deep compression gentle technique also can help to release that problem. In addition, an traditional Thai treatment with Tok Sen (TS) massage has been generally performed in the Northern part of Thailand without any scientific evidence support. Thus, the aim of this preliminary study was to reveal the scientific value of Tok Sen massage on shoulder muscle pain and upper trapezius muscle thickness among people with shoulder pain.

Materials & Methods

Twenty participants (6 males and 14 females) who suffered from shoulder pain were randomized into TS (n =10, aged 34.2 ± 7.34 yrs) or TM (n=10, aged 32.8 ± 7.24 yrs). Each group received two times 5-10 minutes of treatment, one week apart. At the baseline and after completing two times of each intervention, pain score, pain pressure threshold (PPT), and specific trapezius muscle thickness were evaluated.

Results

Before both TM and TS interventions, pain score, PPT, and muscle thickness were not statistically different between groups. After two times of intervention, pain scores significantly reduced in TM (3.1 ± 0.56; p = .02, 2.3 ± 0.48; p < .001), as same as in TS (2.3 ± 0.67; p = .01, 1.3 ± 0.45; p < .001) when compared to baseline. This was the same as the results of PPT in TM (4.02 ± 0.34; p = .012, 4.55 ± 0.42; p = .001) and TS (5.67 ± 0.56; p = .001, 6.8 ± 0.72; p < .001). However, the trapezius muscle thickness reduced significantly after two interventions by TS (10.42 ± 1.04; p = 0.002 & 9.73 ± 0.94 mm, p < .001), but did not change in TM (p > .05). Moreover, when compared between intereventions at the first and second periods, TS showed a significant difference in pain score (p = .01 & p <.001), muscle thickness (p = .008 & p = .001) as well as PPT (p < .001 & p < .001) when compared to TM.

Conclusion

Tok Sen massage improves upper trapezius thickness from muscle spasms and reduces pain perception and increases the pressure threshold pain among participants who suffer from shoulder pain similar to that of office syndrome.

Panoramic ultrasound imaging does not produce muscle morphology deformation during imaging acquisition: A validity study

PURPOSE

Despite panoramic ultrasound imaging (US) is a promising advance for the morphological and histological assessment of large musculature which cannot be entirely assessed using B-mode, there is no evidence assessing if this technology produces muscle deformation during imaging acquisition. We aimed to analyze differences in size, shape and brightness descriptors between B-mode and panoramic US images and to assess the concordance between both methods. Methods We analyzed size (cross-sectional area and perimeter), shape (circularity, aspect ratio and roundness) and brightness (mean echo-intensity) features of cervical multifidus (CM) and short rotators (SR) in 46 healthy volunteers. Images were acquired in B-mode and extended field-of-view mode. For validity analysis, mean differences between methods were calculated. For agreement analysis, intraclass correlation coefficients (ICCs), standard error of measurements (SEM), minimal detectable changes (MDC) and coefficient of variation (CV%) were calculated.

RESULTS

All parameters showed no significant differences between both methods for either CM or SR (P > 0.05). Panoramic US showed excellent concordance with B-mode for assessing all CM parameters (all ICCs > 0.9), while for SR the agreement ranged from good-to-excellent (ICC from 0.861 to 0.978).

CONCLUSION

Panoramic US seems to be a valid tool for assessment of muscle size, shape and brightness as no deformation in comparison with B-mode images was seen. Further research is needed to corroborate these findings comparing panoramic US imaging with Gold Standard methods.

Spinal cord injury without radiological abnormality due to a fall while using an abdominal roller: A report of two cases

Background

In recent years, various home-use health devices have gained popularity. The abdominal roller is one of these. Spinal cord injury without radiological abnormality is known to occur even with relatively minor injuries, but there are few reports of such injuries caused by a roller.

Case Presentation

Two cases of spinal cord injuries caused by a roller are reported. In both cases, injuries occurred during the standing rollout by a patient in an inebriated state, and the patients were rushed to an emergency department.

Conclusion

Because the use of abdominal rollers may result in extremely serious disabilities, it is necessary to emphasize the appropriate use of such equipment.

Relationship between Nutritional Status, Body Composition, Muscle Strength, and Functional Recovery in Patients with Proximal Femur Fracture

Sarcopenia is a major issue among the elderly. However, the effects of nutritional status and body composition on functional recovery in patients with proximal femur fractures (PFF) remain unclear. Hence, this study aimed to investigate the effects of nutritional status, body composition (skeletal muscle mass and muscle quality measured by phase angle [PhA] values), and muscle strength on the improvement in activities of daily living (ADL) in patients with PFF. We enrolled patients with PFF admitted to a rehabilitation unit. Nutritional status, body composition, grip strength, and motor Functional Independence Measure (FIM) score were assessed on admission day and at 4 weeks thereafter. Of 148 patients, 84 had femoral neck fractures, and 64 had trochanteric fractures. The mean motor FIM score was 49.2 points at admission and 64.9 points after 4 weeks. In multivariate analysis, higher geriatric nutritional risk index and PhA measured by anthropometry were associated with a significantly higher FIM score after 4 weeks. Muscle strength and quality changes significantly correlated with ADL improvement. Poor nutritional status and decreased muscle strength and quality interfered with ADL recovery. Nutritional management before injury and from the acute phase, and rehabilitation to maintain skeletal muscle status, are important for ADL recovery.

Using deep learning to predict abdominal age from liver and pancreas magnetic resonance images

With age, the prevalence of diseases such as fatty liver disease, cirrhosis, and type two diabetes increases. Approaches to both predict abdominal age and identify risk factors for accelerated abdominal age may ultimately lead to advances that will delay the onset of these diseases. We build an abdominal age predictor by training convolutional neural networks to predict abdominal age (or "AbdAge") from 45,552 liver magnetic resonance images [MRIs] and 36,784 pancreas MRIs (R-Squared = 73.3 ± 0.6; mean absolute error = 2.94 ± 0.03 years). Attention maps show that the prediction is driven by both liver and pancreas anatomical features, and surrounding organs and tissue. Abdominal aging is a complex trait, partially heritable (h_g² = 26.3 ± 1.9%), and associated with 16 genetic loci (e.g. in PLEKHA1 and EFEMP1), biomarkers (e.g body impedance), clinical phenotypes (e.g, chest pain), diseases (e.g. hypertension), environmental (e.g smoking), and socioeconomic (e.g education, income) factors.

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 (β = -0.25, P = 0.006) and BI score at discharge (β = -0.18, P = 0.006). In contrast, change in quadriceps thickness was not independently and significantly associated with the change in BI score (β = 0.09, P = 0.244) and BI score at discharge (β = 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.

Association of mobility capacity with the masses and amounts of intramuscular non-contractile tissue of the trunk and lower extremity muscles in community-dwelling older adults

We examined the association of mobility capacity with muscle thicknesses and echo intensities of the trunk and lower extremity muscles measured using an ultrasound imaging device in community-dwelling older adults. The participants were 57 community-dwelling older adults. Mobility capacity was assessed based on the measurement of usual and maximal walking speeds and timed up-and-go (TUG) time. Muscle thickness and echo intensity of the trunk and lower extremity muscles were measured using an ultrasound imaging device. Finally, sagittal spinal alignment was assessed based on the measurement of thoracic kyphosis, lumbar lordosis, and sacral anterior inclination angles in the standing position using a Spinal Mouse. Stepwise regression analysis showed that the tibialis anterior muscle thickness, tibialis posterior muscle echo intensity, and body weight were significant and independent factors of usual walking speed, with a coefficient of determination (R²) of 0.25. The thicknesses of the thoracic erector spinae and obliquus externus abdominis muscles were significant and independent factors of maximal walking speed (R² = 0.26). Moreover, only age was a significant and independent factor for TUG time (R² = 0.10). The results of this study suggested associations 1) between slow usual walking speed and low tibialis anterior muscle thicknesses and high echo intensity of the tibialis posterior muscle and 2) between slow maximal walking speed and low thoracic erector spinae and obliquus externus abdominis thicknesses in community-dwelling older adults.

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 (β = -0.13, P < 0.01), BI score change (β = -0.23, P < 0.01), and BI efficiency (β = -0.21, P < 0.01). Quadriceps thickness was not independently and significantly associated with the BI score at discharge (β = -0.02, P = 0.68), BI score change (β = -0.02, P = 0.79), and BI efficiency (β = 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.

Association between knee extensor and ankle plantarflexor muscle thickness and echo intensity with postural sway, mobility and physical function in older adults

The purpose of this study was to assess the association between muscle thickness and echo intensity of the knee extensors and ankle plantarflexors with postural sway, mobility and physical function in older adults. Twenty-one older men and women (age; 69.9 ± 4.3 years) were assessed for postural sway (centre of pressure movement), mobility (i.e. Timed-Up and-Go-test [TUG]), physical function (i.e. 5 times sit-to-stand [STS]), and ultrasound derived measures of muscle thickness and echo intensity of the vastus lateralis (VL) and gastrocnemius medialis (GM). Significant inverse correlations were observed between VL and GM thickness with TUG (r = -0.432 to -0.492) and STS (r = -0.473 to -0.596). Significant positive correlations were observed between VL and GM echo intensity with TUG (r = 0.459 to 0.518) and STS (r = 0.481 to 0.635). Significant positive correlations were also detected between GM echo intensity and anteroposterior sway (r = 0.451 to 0.534). Two key findings emerged from the present experiment. First, this study provides novel evidence that ankle plantarflexor echo intensity, but not thickness, was associated with anteroposterior postural sway among older adults. Second, we provide new evidence that muscle thickness and echo intensity of the knee extensors and uniquely, the ankle plantarflexors, presented with similar magnitude associations with TUG and STS performance in older adults.

Age-Related Change in Muscle Characteristics and Resistance Training for Older Adults

In older adults, muscle weakness contributes greatly to functional restrictions on daily living activities, increased risk of falls, and adverse physiological changes. It has been suggested that not only muscle mass but also muscular infiltration of noncontractile elements may influence muscular performance such as strength and rapid force production. It is proved that resistance training may provoke substantial increases in muscle size even if it is performed at low intensities in older individuals. Also, recent studies have demonstrated the effectiveness of resistance training on muscle quality such as muscular infiltration of noncontractile elements for older people. This review shows the age-related changes in muscle mass and muscle quality, which were measured by muscle echo intensity on ultrasound images, and low-intensity resistance training effects on muscle volume and muscle quality.

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.