Association of computed tomography-derived muscle mass and quality with delayed acquisition independent walking after cardiovascular surgery.

BACKGROUND: In the context of cardiovascular surgery, the foremost concern lies in delayed functional recovery, as typified by the acquisition of independent walking after surgery, among older patients with decline in skeletal muscle mass and quality. Computed tomography (CT), which is typically employed for the preoperative assessment of pathological conditions in patients undergoing cardiovascular surgery, is also suitable for screening for potential decline in skeletal muscle mass and quality. The aim of this study was to examine the predictive capabilities of CT-derived parameters such as muscle mass and muscle quality for the delayed acquisition of independent walking in the postoperative period. METHODS: This retrospective study enrolled consecutive Japanese patients who underwent elective cardiovascular surgery between May 2020 and January 2023. In total, 139 patients were included in the analyses. Based on the preoperative CT image, the psoas muscle volume index (PMVI) and psoas muscle attenuation (PMA) were calculated. Information on patient characteristics, including preoperative physical fitness such as handgrip strength/body mass index (GS/BMI), short physical performance battery (SPPB), and 6-min walking distance (6MWD), were obtained from the medical records. We defined delayed acquisition of independent walking after surgery as the inability to walk 100 m within 4 days after surgery. RESULTS: The median age of the patients was 72 (interquartile: 64-78) years, and 74.8% (104/139) were men; 47.5% corresponded to the delayed group. The areas under the curves of SPPB, GS/BMI, 6MWD, PMVI, and PMA against delayed acquisition of independent walking after surgery were 0.68 [95% confidence interval (CI): 0.59 to 0.77], 0.72 (95% CI: 0.63 to 0.80), 0.73 (95% CI: 0.65 to 0.82), 0.69 (95% CI: 0.60 to 0.78), and 0.78 (95% CI: 0.70 to 0.85), respectively. In the multivariate logistic regression analysis, low PMA was significantly associated with delayed acquisition of independent walking even after adjustment for patient characteristics including physical fitness [model 1: SPPB (OR, 1.14; 95% CI: 1.03-1.25), model 2: GS/BMI (OR, 1.13; 95% CI: 1.03-1.25), and model 3: 6MWD (OR, 1.14; 95% CI: 1.03-1.25)], but PMVI was not. CONCLUSIONS: Our study revealed a strong association between PMA, a marker of CT-derived muscle quality, and the postoperative delay in achieving independent walking in patients who underwent cardiovascular surgery. The technique to obtain information on muscle quality during the time period before surgery may be an option for timely therapeutic intervention in patients who may have delayed acquisition of independent walking after surgery.

Neuromuscular electrical stimulation, muscle mass, and physical function decline in the early phase after living donor liver transplantation.

This study aims to investigate the effects of neuromuscular electrical stimulation (NMES) in addition to conventional early mobilization in the early postoperative period after living donor liver transplantation (LTx) on body composition and physical function. This was a retrospective single-center cohort study. Adult subjects who were admitted for living donor LTx from 2018 to 2023 were included in the analysis. After April 2020, patients underwent 4 weeks of NMES in addition to conventional rehabilitation. The skeletal muscle mass index, body cell mass, and physical function, including the 6-minute walking distance, were assessed before surgery and at discharge, and changes in these outcomes were compared before and after the introduction of NMES. Sixty-one patients were in the NMES group, and 53 patients before the introduction of NMES were in the control group. ANCOVA with etiology, obstructive ventilatory impairment, Child-Pugh classification, and initial body composition value as covariates demonstrated that there was a significantly smaller decline of body cell mass (-2.9±2.7 kg vs. -4.4±2.7 kg, p = 0.01), as well as of the skeletal muscle mass index (-0.78±0.73 kg/m2 vs. -1.29±1.21 kg/m2, p = 0.04), from baseline to discharge in the NMES group than in the control group; thus, the decline after surgery was suppressed in the NMES group. Four weeks of NMES, in addition to conventional rehabilitation in the early period after LTx, may attenuate the deterioration of muscle mass. It is suggested that NMES is an option for developing optimized rehabilitation programs in the acute postoperative period after LTx.

Definition, diagnosis, and treatment of respiratory sarcopenia.

PURPOSE OF REVIEW: Skeletal muscle weakness and wasting also occurs in the respiratory muscles, called respiratory sarcopenia. Respiratory sarcopenia may lead to worse clinical indicators and outcomes. We present a novel definition and diagnostic criteria for respiratory sarcopenia, summarize recent reports on the association between respiratory sarcopenia, physical and nutritional status, and clinical outcomes, and provide suggestions for the prevention and treatment of respiratory sarcopenia. RECENT FINDINGS: Recently, a novel definition and diagnostic criteria for respiratory sarcopenia have been prepared. Respiratory sarcopenia is defined as a condition in which there is both low respiratory muscle strength and low respiratory muscle mass. Respiratory muscle strength, respiratory muscle mass, and appendicular skeletal muscle mass are used to diagnose respiratory sarcopenia. Currently, it is challenging to definitively diagnose respiratory sarcopenia due to the difficulty in accurately determining low respiratory muscle mass. Decreased respiratory muscle strength and respiratory muscle mass are associated with lower physical and nutritional status and poorer clinical outcomes. Exercise interventions, especially respiratory muscle training, nutritional interventions, and their combinations may effectively treat respiratory sarcopenia. Preventive interventions for respiratory sarcopenia are unclear. SUMMARY: The novel definition and diagnostic criteria will contribute to promoting the assessment and intervention of respiratory sarcopenia.

Physical activity measurements in individuals with interstitial lung disease: a systematic review and meta-analysis.

BACKGROUND: Physical activity (PA) measurements are becoming common in interstitial lung disease (ILD); however, standardisation has not been achieved. We aimed to systematically review PA measurement methods, present PA levels and provide practical recommendations on PA measurement in ILD. METHODS: We searched four databases up to November 2022 for studies assessing PA in ILD. We collected information about the studies and participants, the methods used to measure PA, and the PA metrics. Studies were scored using 12 items regarding PA measurements to evaluate the reporting quality of activity monitor use. RESULTS: In 40 of the included studies, PA was measured using various devices or questionnaires with numerous metrics. Of the 33 studies that utilised activity monitors, a median of five out of 12 items were not reported, with the definition of nonwear time being the most frequently omitted. The meta-analyses showed that the pooled means (95% CI) of steps, time spent in moderate to vigorous PA, total energy expenditure and sedentary time were 5215 (4640-5791) steps·day-1, 82 (58-106) min·day-1, 2130 (1847-2412) kcal·day-1 and 605 (323-887) min·day-1, respectively, with considerable heterogeneity. CONCLUSION: The use of activity monitors and questionnaires in ILD lacks consistency. Improvement is required in the reporting quality of PA measurement methods using activity monitors.

Relationship Between Physical Activity and Estimated Glomerular Filtration Rate in Renal Transplant Recipients: A Cross-sectional Study Analyzing Isotemporal Substitution Model.

OBJECTIVES: Successful renal transplantation reduces mortality rates. However, the decline in the estimated glomerular filtration rate (eGFR) after transplantation is strongly associated with premature mortality in renal transplant recipients (RTRs). Physical activity (PA) is a modifiable lifestyle factor with the potential to maintain or improve eGFR. However, the effects of the type or intensity of PA and sedentary behavior (SB) on eGFR in RTRs remain unclear. The purpose of this study was to clarify the association between accelerometry-measured PA and SB and eGFR in RTRs using isotemporal substitution (IS) analysis. METHODS: A total of 82 renal transplant outpatients participated in this cross-sectional study, of which 65 (average age, 56.9 years; average time post-transplant, 83.0 months) were finally analyzed. All RTRs wore a triaxial accelerometer to measure PA for 7 consecutive days. The measured PA was classified based on intensity into light PA, moderate-to-vigorous PA (MVPA), and SB. The association of each type of PA with eGFR was examined using multi-regression analyses of single-factor, partition, and IS models. The IS model was applied to examine the estimated effects of substituting 30 minutes of SB with an equal amount of time of light PA or MVPA on eGFR. RESULTS: The partition model showed that MVPA was an independent explanatory variable for eGFR (ß = 5.503; P < .05), and the IS model identified that the substitution of time spent in SB with MVPA led to improvements in eGFR (ß = 5.902; P < .05). CONCLUSIONS: The present study suggests that MVPA has an independent and positive association with eGFR, and replacing 30 minutes of SB with MVPA after renal transplantation might lead to the maintenance or improvement of eGFR in RTRs.

Heart Failure Management Capability and Exacerbation of Heart Failure　- A 6-Month Prospective Cohort Study.

Background: In households with older individuals, where a patient is experiencing heart failure (HF), effective cooperation between patients and caregivers is crucial for disease management. However, there is limited evidence regarding the impact of cooperative HF management on the incidence of exacerbation. Therefore, the aim of this 6-month prospective cohort study was to investigate the association between HF management capability and exacerbations. Methods and Results: The study enrolled outpatients (age ≥65 years) with chronic HF from a cardiology clinic and their caregivers. Self-care capabilities among patients and caregivers were evaluated using the Self-Care of Heart Failure Index (SCHFI) and Caregiver Contribution-SCHFI, respectively. Total scores were calculated using the highest score for each item. During the follow-up period, 31 patients experienced worsening HF. The analysis revealed no significant association between the total HF management score and HF exacerbation among all eligible patients. However, in patients with preserved left ventricular ejection fraction (LVEF), high HF management capability of the family unit was associated with a reduced risk of HF exacerbation, even after adjusting for the severity of HF. Conclusions: In older patients with HF and preserved LVEF, effective HF management may contribute to a lower risk of exacerbations.

The effectiveness of an accelerometer-based physical activity enhancement intervention for patients undergoing lung resection - A pilot randomized controlled trial.

OBJECTIVES: Increasing physical activity after lung resection is important for maintaining quality of life. It is unclear whether accelerometer-based exercise instruction contributes to increasing daily physical activity after lung resection. We examine whether accelerometer-based exercise instruction will lead to increased physical activity in patients undergoing lung resection. MATERIALS AND METHODS: Forty-six patients undergoing lung resection were randomly assigned to either the intervention group (n = 22) or the control group (n = 24). Twelve participants dropped out. Ultimately, 16 participants in the intervention group and 18 participants in the control group were eligible for analysis. Each group allocation was only known to the person in charge of allocation. The physiotherapists and assessors were not blinded in this study. The intervention group participated in a postoperative rehabilitation program and received physical activity instruction preoperatively and at discharge. The control group participated in a postoperative rehabilitation program only. The primary outcomes was physical activity such as the number of daily steps, light intensity physical activity (LPA) and moderate-vigorous intensity physical activity (MVPA) at the two month postoperative follow-up. RESULTS: Thirty-four participants were enrolled in this study. Sixteen participants in the intervention group and 18 participants in the control group were included for analysis. Although there was no significant difference in physical activity at baseline, the number of daily steps in the intervention group at the two month postoperative follow-up was significantly higher than that in the control group (8039.2 ± 3480.8 vs. 4887.0 ± 2376.5 steps/day, p = 0.004). Compared to the control group, the intervention group also had greater increases in LPA (63.8 ± 25.1 vs. 44.5 ± 24.5 min/day, p = 0.030) and MVPA (20.2 ± 19.6 vs. 9.6 ± 8.6 min/day, p = 0.022). CONCLUSIONS: This study showed that accelerometer-based exercise instruction led to an increase in physical activity after lung resection in an unsupervised setting. CLINICAL TRIAL REGISTRATION: The University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN trial No. UMIN000039369).

Survival and cognitive deterioration in elderly patients undergoing hemodialysis.

AIM: This study aimed to elucidate the 5-year changes in the cognitive function of elderly patients undergoing hemodialysis and its association with survival and related factors. METHODS: Cognitive function in patients aged ≥65 years undergoing hemodialysis at the Nagasaki Renal Center was assessed using the Mini-Mental State Examination (MMSE) in 2016. Patients were subsequently classified into normal, mild cognitive impairment (MCI) and suspected dementia groups according to their scores; MMSE was conducted at 30 and 60 months thereafter. The patients were followed until 2021. The association between survival and patient backgrounds was analyzed. RESULTS: Of the 181 patients, 168 completed follow-up and were classified into normal (n = 71, 42.3%), MCI (n = 44, 26.1%), and suspected dementia (n = 53, 31.5%) groups. Multivariable logistic regression analysis showed that age, female sex, and geriatric nutritional risk index were associated with MMSE scores <24. The 5-year survival rates were 60.6%, 40.9%, and 22.6% in the normal, MCI and suspected dementia groups, respectively. With some exceptions, MMSE results tended to decline during the observation period. A multivariate Cox proportional hazards model showed that age (hazard ratio [HR], 1.04; P = 0.007), dialysis vintage (HR, 0.96; P = 0.04), male sex (HR, 1.77; P = 0.02), geriatric nutritional risk index (HR, 0.94; P < 0.001) and MMSE score (HR, 0.96; P = 0.01) were independent risk factors for patient survival. CONCLUSIONS: Cognitive impairment in patients undergoing hemodialysis was associated with age and nutritional status. Patients with cognitive impairment had a poor prognosis. Geriatr Gerontol Int 2023; 23: 111-116.

Poor prognosis after lower-limb amputation irrespective of diabetes status in patients undergoing hemodialysis.

INTRODUCTION: Diabetes mellitus is one of the most important risk factors for lower-limb amputation in patients undergoing hemodialysis. However, the influence of diabetes mellitus on survival after lower-limb amputation is unknown. METHODS: Patients who underwent lower-limb amputation since 1996 (amputation group) and those who underwent hemodialysis during 2011-2012 (control group) were included and were followed up until July 2022. RESULTS: There were 70 patients (age: 66.3 ± 8.2 years, 80% male, 77% diabetic) in the amputation group and 328 (age: 67.5 ± 13.5 years, 56% male, 33% diabetic) in the control group. The amputation group showed a poorer prognosis than the control group (hazard ratio [HR]: 2.41, p < 0.001). In the control group, patients with diabetes exhibited poorer survival than those without diabetes (HR: 1.86, p < 0.001). In the amputation group, patients with diabetes exhibited improved survival (HR: 0.47, p = 0.02). CONCLUSION: Patients undergoing hemodialysis who underwent lower-limb amputation exhibited a poor prognosis, irrespective of diabetes status.

Respiratory sarcopenia: A position paper by four professional organizations.

We defined respiratory sarcopenia as a coexistence of respiratory muscle weakness and decreased respiratory muscle mass. Although respiratory muscle function is indispensable for life support, its evaluation has not been included in the regular assessment of respiratory function or adequately evaluated in clinical practice. Considering this situation, we prepared a position paper outlining basic knowledge, diagnostic and assessment methods, mechanisms, involvement in respiratory diseases, intervention and treatment methods, and future perspectives on respiratory sarcopenia, and summarized the current consensus on respiratory sarcopenia. Respiratory sarcopenia is diagnosed when respiratory muscle weakness and decreased respiratory muscle mass are observed. If respiratory muscle mass is difficult to measure, we can use appendicular skeletal muscle mass as a surrogate. Probable respiratory sarcopenia is defined when respiratory muscle weakness and decreased appendicular skeletal muscle mass are observed. If only respiratory muscle strength is decreased without a decrease in respiratory function, the patient is diagnosed with possible respiratory sarcopenia. Respiratory muscle strength is assessed using maximum inspiratory pressure and maximum expiratory pressure. Ultrasonography and computed tomography are commonly used to assess respiratory muscle mass; however, there are insufficient data to propose the cutoff values for defining decreased respiratory muscle mass. It was jointly prepared by the representative authors and authorized by the Japanese Society for Respiratory Care and Rehabilitation, Japanese Association on Sarcopenia and Frailty, Japanese Society of Respiratory Physical Therapy and Japanese Association of Rehabilitation Nutrition. Geriatr Gerontol Int 2023; 23: 5-15.

Simplified discriminant parameters for sarcopenia among patients undergoing haemodialysis.

BACKGROUND: Patients with end-stage renal disease (ESRD) are at an increased risk of developing sarcopenia, which can lead to various adverse health outcomes. Although the diagnosis of sarcopenia is essential for clinical management, it is not feasible in routine clinical practice for populations undergoing haemodialysis because it is time-consuming and resources are limited. Serum creatinine levels in patients with ESRD have been gaining attention as a screening parameter for sarcopenia because serum creatinine is a routinely measured byproduct of skeletal muscle metabolism. This study aimed to evaluate the discriminative ability of the creatinine-derived index for sarcopenia in patients undergoing haemodialysis. METHODS: We diagnosed sarcopenia according to the Asian Working Group for Sarcopenia (AWGS) 2 criteria in 356 clinically stable outpatients with ESRD enrolled from three dialysis facilities. We adopted the modified creatinine index as a simplified discriminant parameter for sarcopenia in addition to the calf circumference, SARC-F score, and combination of both (i.e. SARC-CalF score), which are recommended by the AWGS. Receiver operating characteristic analysis and logistic regression analysis were conducted to evaluate the discriminative ability of the modified creatinine index for sarcopenia. RESULTS: Of the study participants, 142 (39.9%) were diagnosed with sarcopenia. The areas under the curve of the modified creatinine index against sarcopenia in the male and female participants were 0.77 (95% confidence interval [CI]: 0.71 to 0.83) and 0.77 (95% CI: 0.69 to 0.85), respectively. All simplified discriminant parameters were significantly associated with sarcopenia, even after adjusting for patient characteristics and centre. In the comparison of the odds ratios for sarcopenia for 1-standard deviation change in the simplified discriminant parameters, the odds ratio of the modified creatinine index was 1.92 (95% CI: 1.15 to 3.19), which was lower than that of the calf circumference (odds ratio: 6.58, 95% CI: 3.32 to 13.0) and similar to that of the SARC-F (odds ratio: 1.57, 95% CI: 1.14 to 2.16) and SARC-CalF scores (odds ratio: 2.36, 95% CI: 1.60 to 3.47). CONCLUSIONS: This study revealed a strong association between the creatinine-derived index and sarcopenia in patients undergoing haemodialysis. The modified creatinine index was equal or superior to those of SARC-F and SARC-CalF score in discriminability for sarcopenia. However, the ability of the calf circumference to discriminate sarcopenia is extremely high, and further study is needed to determine whether it can be used to detect deterioration of muscle mass and function over time.

Linguistic Validation of the Japanese Version of the Multidimensional Dyspnea Profile and Relation to Physical Activity in Patients with COPD.

PURPOSE: This study aimed to develop a linguistically validated Japanese translation of the multidimensional dyspnea profile (MDP) and assess whether worsening of dyspnea's sensory and affective domains during exercise had detrimental effects on physical activity in stable outpatients with chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: The Japanese version of the MDP was prepared in collaboration with Mapi Research Trust (Lyon, France) after the approval of the developer. Physical activity was assessed using a 3-axis accelerometer. Dyspnea upon exertion was investigated using a 3-minute step test. RESULTS: The Japanese version of the MDP was obtained and validated linguistically. Air-hunger was significantly associated with total calories from walking (r = - 0.47, p < 0.05), while anxiety and depression were significantly correlated with both the amount and intensity of physical activity (r = - 0.49, p < 0.05, and r = - 0.46, p < 0.05, respectively). CONCLUSION: The Japanese version of the MDP was suggested to reflect both pulmonary functions, ventilatory response during exercise, and intensity and amount of physical activity in patients with COPD.

Effect of Home-based Exercise Therapy for Peripheral Arterial Disease Patients Underwent Endovascular Treatment: A Clinical Controlled Design.

OBJECTIVE: This study aimed to clarify the effect of home-based exercise therapy on physical activity in peripheral arterial disease (PAD) patients after EVT. METHODS: Study design was controlled clinical design. The subjects were 30 patients (76.6% men) who underwent EVT in the Sakakibara Heart Institute of Okayama. Patients with EVT meeting the inclusion criteria were divided into two groups, intervention group (Home-based exercise) and control group. Patients' basic characteristics, the number of steps walked and QOL questionnaire (WIQ, SEPA, Vascu QOL) were assessed before surgery and, at the 3 month after discharge. A two-way analysis of variance (ANOVA) was performed to compare number of steps walked and QOL questionnaire. RESULTS: Interaction effect were observed in the number of steps walked (F (1,28) =13.89, p<0.01). A multiple comparison test confirmed a significant increase between results of before surgery and at three months after surgery in the intervention group (p<0.01). An interaction between the presence and absence of intervention was found for the WIQ pain score (F(1,28) = 5.86, p=0.01), speed score (F(1,28) = 3.80, p=0.04) and SEPA (F(1,28) = 4.99, p=0.03). In a multiple comparison study, there was a significant increase in WIQ pain and speed scores in both groups before and 3 months after discharge from the hospital. CONCLUSION: Home-based exercise therapy using physical activity indices has the potential to improve number of steps and quality of life in patients with PAD after EVT.

The effects of amino acid/protein supplementation in patients undergoing hemodialysis: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND & AIMS: We evaluated the efficacy of the intervention consisting of amino acid/protein supplementation on muscle mass, muscle strength and physical function in patients on hemodialysis. METHODS: This systematic review and meta-analysis identified potential studies through a systematic search of 4 electronic databases and references from eligible studies from database inception to August 2020. We included only randomized controlled trials reporting the efficacy of amino acid/protein supplementation on muscle mass, muscle strength and physical function in patients on hemodialysis. RESULTS: Of 6529 unique citation records, 4 studies including 243 participants were selected for inclusion in the meta-analysis. Although there were no significant differences in muscle mass and muscle strength between the intervention and control groups, amino acid/protein supplementation was shown to significantly improve physical function (shuttle walk, MD 32.7, 95% CI 21.7 to 43.7, P < 0.001; gait speed, MD 0.07, 95% CI 0.01 to 0.13, P = 0.02; timed up and go, MD -0.42, 95% CI -0.68 to -0.15, P = 0.002) in patients on hemodialysis. CONCLUSIONS: We confirmed the positive effect of amino acid/protein supplementation on physical function in people undergoing hemodialysis. However, there is still insufficient evidence, and more rigorously designed randomized controlled trials with high quality are needed.

Predictors of Functional Decline in Activities of Daily Living at Discharge in Patients After Cardiovascular Surgery.

BACKGROUND: This study aimed to investigate the trajectory of functional recovery of activities of daily living (ADL) from the time of admission up to hospital discharge, and explored which preoperative and postoperative variables were independently associated with functional decline in ADL at discharge of patients after cardiovascular surgery.Methods and Results:In this observational study, we evaluated ADL preoperatively and at discharge using the Functional Independence Measure (FIM) in patients after cardiovascular surgery. Functional decline in ADL was defined as scoring 1-5 on any one of the FIM items at discharge. Multiple logistic regression was performed to predict the functional decline in ADL at discharge. We found that 18.8% of elective cardiovascular surgery patients suffered from decreased ADL at discharge. The Mini-Mental State Examination (odds ratio (OR): 0.573, 95% confidence interval (CI): 0.420-0.783), gait speed (OR: 0.032, 95% CI: 0.003-0.304) and initiation of walking around the bed (OR: 1.277, 95% CI: 1.103-1.480) were independently associated with decreased ADL at discharge. CONCLUSIONS: A functional decline in ADL at discharge can be predicted using preoperative measures of cognitive function, preoperative gait speed and postoperative day of initiation of walking. These results show that preoperative cognitive screening and gait speed assessments can be used to identify patients who might require careful postoperative planning, and for whom early postoperative rehabilitation is needed to prevent serious functional ADL deficits.

The clinical applicability of ultrasound technique for diagnosis of sarcopenia in hemodialysis patients.

BACKGROUND & AIMS: We examined the validity of ultrasound technique assessing muscle mass and reflecting muscle strength and physical performance, and the clinical applicability of ultrasound as a diagnostic tool of sarcopenia in patients on hemodialysis. METHODS: This study included outpatients who were undergoing maintenance hemodialysis 3-time a week. Muscle mass, muscle strength and physical performance were assessed at the time of the patients' entry into the study. Ultrasound technique and bioelectrical impedance analysis (BIA) were used to estimate muscle mass. The cross-sectional area (CSA) of the rectus femoris was calculated using an ultrasound device built-in planimeter. RESULTS: A total of 58 hemodialysis patients were included in the analyses. Ultrasound-derived muscle mass was strongly correlated with BIA-derived measurements and independently associated with handgrip strength (ß = 4.22, 95% confidence interval [CI] = 2.23-6.20, P < 0.001), gait speed (ß = 0.15, 95% CI = 0.05-0.26, P = 0.006), chair stand time (ß = -4.33, 95% CI = -7.34 to -1.31, P = 0.006), and SPPB score (ß = 1.81, 95% CI = 0.46-3.15, P = 0.010) even after adjustment of patient characteristics. The discrimination ability of CSA of rectus femoris for muscle loss was high. Of the patients who were diagnosed with sarcopenia by the ultrasound-based criteria, 96% met the BIA-based criteria. CONCLUSIONS: Ultrasound identified the patients at higher risk of skeletal muscle loss and sarcopenia with good discriminatory power. Ultrasound could be a valid and feasible technique for dialysis populations in clinical settings.

Determinants of Health-Related Quality of Life and Physical Performance-Based Components of Frailty in Patients Undergoing Hemodialysis.

OBJECTIVES: Health-related quality of life (HRQoL) measures capture the patient's experience of the burden of chronic disease and are strongly associated with adverse health-related outcomes across multiple populations. The SF-36 score is the most widely used HRQoL measure among patients with end-stage renal disease. Current understanding of determinants of the physical component summary (PCS) and the mental component summary (MCS) and their association with objectively measured physical performance and activity is limited. METHODS: As an index of HRQoL, we prospectively examined the association of SF-36 and its component scores with physical function among 155 incident dialysis patients from the Hemodialysis Center. We investigated associations of HRQoL with the physical performance-based components of the frailty using multivariate linear and logistic regression after adjustment for confounders. Impaired physical performance was defined as having either slow usual gait speed or weak handgrip strength based on standardized and validated criteria derived from a large cohort study of older adults. RESULTS: The patients had a mean age of 65 ± 11 years, and 52.3% were male. After adjusting confounders, lower PCS was independently associated with decreased physical performance and reduced physical activity, but MCS was not associated. Among the PCS subscales, only physical functioning 10 (PF-10) was consistently associated with outcomes, and every 1 point increase in PF-10 score was associated with 4% lower odds of impaired physical performance (95% confidence interval 2-7, P = .01) after adjustment. CONCLUSIONS: SF-36, especially PF-10, is a valid surrogate that discriminates low physical performance and physical inactivity in the absence of formal physical function testing in patients on hemodialysis. The routine implementation of the PF-10 in clinical care has important clinical implications for medical management and therapeutic decision-making in patients undergoing hemodialysis.

Combined effects of solar radiation and airflow on endurance exercise capacity in the heat.

This study investigated the combined effects of different levels of solar radiation and airflow on endurance exercise capacity and thermoregulatory responses during exercise-heat stress. Ten males cycled at 70% peak oxygen uptake until exhaustion in an environmental chamber (30°C, 50% relative humidity). Four combinations of solar radiation and airflow were tested (800 W⋅m-2 and 10 km⋅h-1 [High-Low], 800 W⋅m-2 and 25 km⋅h-1 [High-High], 0 W⋅m-2 and 10 km⋅h-1 [No-Low], and 0 W⋅m-2 and 25 km⋅h-1 [No-High]). Participants were exposed to solar radiation by a ceiling-mounted solar simulator (Metal halide lamps) and the headwind by two industrial fans. Time to exhaustion was shorter (p < 0.05) in High-Low (mean ± SD; 35 ± 7 min) than the other trials and in High-High (43 ± 6 min) and No-Low (46 ± 9 min) than No-High (61 ± 9 min). There was an interaction effect in total (dry + evaporative) heat exchange which was less in High-Low and High-High than No-Low and No-High, and in No-Low than No-High (all p < 0.001). Core temperature, heart rate and thermal sensation were higher in high (High-Low and High-High) than no (No-Low and No-High) solar radiation trials and in lower (High-Low and No-Low) than higher (High-High and No-High) airflow trials (p < 0.05). Mean skin temperature and rating of perceived exertion were higher in high than no solar radiation trials (p < 0.05). This study indicates that combining high solar radiation and lower airflow have negative effects on thermoregulatory and perceptual strain and endurance exercise capacity than when combining high solar radiation and higher airflow and combining no solar radiation and lower/higher airflow during exercise-heat stress.

Quantity and quality of antigravity muscles in patients undergoing living-donor lobar lung transplantation: 1-year longitudinal analysis using chest computed tomography images.

BACKGROUND: Skeletal muscle dysfunction is a common feature in patients with severe lung diseases. Although lung transplantation aims to save these patients, the surgical procedure and disuse may cause additional deterioration and prolonged functional disability. We investigated the postoperative course of antigravity muscle condition in terms of quantity and quality using chest computed tomography. METHODS: 35 consecutive patients were investigated for 12 months after living-donor lobar lung transplantation (LDLLT). The erector spinae muscles (ESMs), which are antigravity muscles, were evaluated, and the cross-sectional area (ESMCSA) and mean attenuation (ESMCT) were analysed to determine the quantity and quality of ESMs. Functional capacity was evaluated by the 6-min walk distance (6MWD). Age-matched living donors with lower lobectomy were evaluated as controls. RESULTS: Recipient and donor ESMCSA values temporarily decreased at 3 months and recovered by 12 months post-operatively. The ESMCSA of recipients, but not that of donors, surpassed baseline values by 12 months post-operatively. Increased ESMCSA (ratio to baseline ≥1) may occur at 12 months in patients with a high baseline ESMCT. Although the recipient ESMCT may continuously decrease for 12 months, the ESMCT is a major determinant, in addition to lung function, of the postoperative 6MWD at both 3 and 12 months. CONCLUSION: The quantity of ESMs may increase within 12 months after LDLLT in recipients with better muscle quality at baseline. The quality of ESMs is also important for physical performance; therefore, further approaches to prevent deterioration in muscle quality are required.

Rising vs. falling phases of core temperature on endurance exercise capacity in the heat.

PURPOSE: Core temperature (Tc) shows rising (05:00-17:00 h) and falling (17:00-05:00 h) phases. This study examined the time-of-day effects on endurance exercise capacity and heat-loss responses to control Tc in the heat at around the midpoint of the rising and falling phases of Tc. METHODS: Ten male participants completed cycling exercise at 70% peak oxygen uptake until exhaustion in the heat (30 °C, 50% relative humidity). Participants commenced exercise in the late morning at 10:00 h (AM) or evening at 21:00 h (PM). RESULTS: Time to exhaustion was 28 ± 13% (mean ± SD) longer in PM (49.1 ± 16.3 min) than AM (38.7 ± 14.6 min; P < 0.001). Tc before and during exercise were higher in PM than AM (both P < 0.01) in accordance with the diurnal variation of Tc. The rates of rise in Tc, mean skin temperature, thermal sensation and rating of perceived exertion during exercise were slower in PM than AM (all P < 0.05). Dry and evaporative heat losses and skin blood flow during exercise were greater in PM than AM (all P < 0.05). During 30-min post-exercise recovery, the rates of fall in Tc and skin blood flow were faster and thermal sensation was lower in PM than AM (all P < 0.05). CONCLUSIONS: This study indicates that endurance exercise capacity is greater and heat-loss responses to control Tc during and following exercise in the heat are more effective in the late evening than morning. Moreover, perceived fatigue during exercise and thermal perception during and following exercise are lower in the late evening than morning.