Impact of Skeletal Muscle Mass on Long-Term Adverse Cardiovascular Outcomes in Patients With Chronic Kidney Disease

Factors Affecting Psoas Muscle Mass Index in Patients Undergoing Peritoneal Dialysis

INTRODUCTION

Many patients with chronic kidney disease (CKD), including peritoneal dialysis (PD), have sarcopenia. It is important to evaluate muscle mass to prevent sarcopenia in the field of CKD management. Recently, muscle mass assessment using psoas muscle evaluated by computed tomography (CT) has been reported in patients undergoing hemodialysis. However, few clinical studies have investigated the clinical factors associated with the evaluation of psoas muscle in patients undergoing PD.

METHODS

Psoas muscle mass index (PMI) was measured in cross-sectional areas of the bilateral psoas muscles at the third lumbar spine level to evaluate psoas muscle status. The associations between PMI and possible clinical factors were investigated in 68 patients undergoing PD.

RESULTS

The mean PMI was 6.3 ± 2.0 cm2/m2, and the PMI was higher in men than in women (p < 0.001). In a multivariable linear regression analysis of the factors associated with PMI, male gender (standardized coefficient: 0.331), body mass index (standardized coefficient: 0.283), serum creatinine concentration (standardized coefficient: 0.289), serum albumin concentration (standardized coefficient: 0.235), and the use of vitamin D (standardized coefficient: 0.195) were independently identified.

CONCLUSION

PMI was independently and significantly associated with gender, BMI, serum creatinine concentration, serum albumin concentration and the use of vitamin D. Further prospective studies are needed to clarify whether the maintenance of nutritional status or vitamin D administration could affect muscle mass in patients undergoing PD.

Mitigating Sarcopenia with Diet and Exercise

Sarcopenia is the loss of muscle mass and function from aging, inactivity, or disuse. It is a comorbidity to numerous conditions that exacerbates their severity and adversely impacts activities of daily living. While sarcopenia now receives more attention from the medical community, people with sarcopenia as a comorbidity nevertheless still sometimes receives less attention than other presenting diseases or conditions. Inevitable doctors' visits or hospital stays for those with sarcopenia as a comorbidity have far higher healthcare costs than those without this condition, which imposes a greater financial burden on the medical insurance and healthcare industries. This review offers information and guidance on this topic. Treatments for sarcopenia include dietary, exercise, and pharmacological interventions. Yet, the latter treatment is only recommended in extreme cases as it may evoke numerous side effects and has little support in the scientific literature. Currently, a more holistic approach, with an emphasis on lifestyle modification, to reduce the likelihood of sarcopenia is examined. The current review discusses dietary and exercise interventions to limit the occurrence and severity of sarcopenia. References cited in this review conformed to the Declaration of Helsinki requirements for the use of human research subjects. Most of this review's references (~97%) came from a PubMed search that spanned from 1997 to 2023. Search terms included "sarcopenia" OR "muscle wasting" OR "geriatrics"; OR "ageing"; and AND "diet" OR "exercise". In addition, papers relevant or supportive of the topic as well as those considered seminal were included in the review. Over 96% of the references were peer-reviewed articles.

Contribution of low skeletal muscle mass in predicting cardiovascular events: A prospective cohort study

BACKGROUND

We aimed to explore the association between skeletal muscle mass and cardiovascular events, and its additional value on the assessment of cardiovascular diseases (CVD) over traditional risk scores.

METHODS

The study included 1365 community-based participants aged over 50 years and free of CVDs at baseline. Participants completed detailed assessments at baseline and received a follow-up assessment in 2021-2022 via phone calls or electronic medical records. Skeletal muscle mass was measured using an automatic bioelectric analyzer. Predicted probabilities of 10-year atherosclerotic cardiovascular disease (ASCVD) risk were estimated individually with the China-PAR equation.

RESULTS

After a mean follow-up of 7.6 years, 144 cardiovascular events were identified. The fully-adjusted hazard ratios (HRs) of cardiovascular events were 0.93 (0.88-0.98) and 1.08 (1.04-1.12) for skeletal muscle mass and predicted 10-year risk, respectively. Among participants over 60 years and with two or more risk factors, cardiovascular events risk increased progressively with each decreasing skeletal muscle tertile. Receiver operating characteristic curves showed that the C-statistic of predicting cardiovascular events for a 10-year risk assessment was slightly increased after adding skeletal muscle mass. The categorical net reclassification improvement (NRI) showed a 56.7% increase in the reclassification. The continuous NRI and integrated discrimination improvement increased as well.

CONCLUSION

Participants with low skeletal muscle mass were more likely to have cardiovascular events. Low muscle mass improved the predictive power of CVD incidence over the original risk score, indicating that muscle mass could be a valuable parameter and a declining value needed early detection in the population.

Sarcopenic obesity and its relation with muscle quality and mortality in patients on chronic hemodialysis

BACKGROUND & AIMS

Sarcopenia is prevalent in patients with end-stage kidney disease (ESKD) on hemodialysis (HD), and is associated with poor outcomes, while obesity may be protective. Sarcopenic obesity is associated with increased frailty, morbidity and mortality in the general population. Myosteatosis, i.e., muscle fat infiltration, has major effects on muscle strength and physical performance, but is poorly investigated in the nephrology setting. In the present study we aimed to assess the association between sarcopenic obesity, as diagnosed by abdominal CT, and mortality. Moreover, the relationship between myosteatosis, sarcopenic obesity and mortality was also investigated.

METHODS

This is a retrospective study in which ESKD patients on HD submitted to unenhanced abdominal CT for clinical reasons at least 6 months after dialysis initiation were evaluated for sarcopenic obesity and myosteatosis, defined as intermuscular fat area and low attenuation muscle area. Sarcopenic obesity was diagnosed in cases of low abdominal skeletal muscle area and high total fat area. Receiver-operating characteristics (ROC) analysis with Youden index was used to determine the cut-off for high total fat area. Intermuscular fat area and low attenuation muscle area were evaluated by applying the Hounsfield unit of interest (-190; -30, and -29; +29 respectively). Cox regression analysis was used to evaluate the association between predictors and mortality risk.

RESULTS

We enrolled 212 patients, aged 68.8 (±14.7) years, 65.5% (139/212) male. Median follow-up was 19.7 (interquartile range [IQR] 2.7-35) months. Sarcopenic obesity was diagnosed in 19.8% of patients and was associated with increased mortality (HR: 3.29 (1.72; 6.27), P < 0.001), and with the presence of myosteatosis. Both intermuscular fat area and low attenuation muscle area were associated with increased mortality in adjusted analyses.

CONCLUSIONS

Patients with sarcopenic obesity have increased myosteatosis. Sarcopenic obesity and myosteatosis are associated with increased mortality in patients on HD.

Impact of muscle loss in children with hematologic malignancies undergoing allogeneic hematopoietic cell transplantation

The widespread recognition of the concept of sarcopenia, or muscle loss, has impacted the prognosis of patients undergoing high-intensity treatments. We focused on the effect of muscle loss on the prognosis of pediatric patients with hematologic diseases. A total of 65 patients with hematologic malignancies who underwent allogeneic HCT once were investigated. The change in cross-sectional psoas muscle area (PMA) measured on computed tomography (CT) images was expressed as the muscle loss index (MLI), which was calculated by dividing the pre-HCT PMA by the baseline PMA. In this study, patients with MLI values less than 0.85 were classified into the muscle loss group. Muscle loss was observed in 27 patients (41.5%). Patients who experienced muscle loss were older than those who did not. Muscle loss was an independent predictor of higher non-relapse mortality (NRM) (p = 0.012) and inferior overall survival (OS) (p = 0.045) at 5 years. Multivariate analysis showed that muscle loss was an independent risk factor for higher NRM (p = 0.046), and inferior EFS (p = 0.048). Muscle loss observed pre-HCT may be a predictor of increased NRM, poor OS and EFS in pediatric patients with hematologic malignancies undergoing allogeneic HCT.

Allograft function and muscle mass evolution after kidney transplantation

BACKGROUND

Advanced chronic kidney disease is associated with muscle wasting, but how glomerular filtration rate (GFR) recovery after kidney transplantation is associated with muscle mass is unknown.

METHODS

We took advantage of the simultaneous measurement of GFR (using iohexol plasma clearance; ioGFR) and creatinine excretion rate (a surrogate marker of muscle mass; CER) performed 3 months after transplantation and at a later time point at our institution to investigate the interplay between allograft function, muscle mass, and outcome in kidney transplant recipients.

RESULTS

Between June 2005 and October 2019, 1319 successive kidney transplant recipients (mean age 50.4 ± 14.6; 38.7% female) underwent GFR measurement at our institution 3 months after kidney transplantation. CER (CER₃ ) and ioGFR (ioGFR₃ ) were 7.7 ± 2.6 μmol/min and 53 ± 17.1 mL/min/1.73 m² , respectively. Multivariable analysis identified female gender, older donor and recipient age, reduced body mass index, coronary disease, dialysis history, proteinuria, and reduced ioGFR₃ as independent predictors of low CER₃ (ioGFR₃ : β coefficient 0.19 [95% confidence interval 0.14 to 0.24]). A total of 1165 patients had a subsequent CER measurement after a median follow-up of 9.5 months. Of them, 373 (32%) experienced an increase in CER > 10%, while 222 (19%) showed a CER decrease of more than 10%. Multivariable analysis adjusted for CER₃ and other confounders identified ioGFR₃ as an independent predictor of CER at follow-up (β coefficient 0.11 [95% confidence interval 0.07 to 0.16]). In multivariable Cox analysis, reduced CER at 3 months or at follow-up were consistently associated with mortality (hazard ratio [95% confidence interval] at 3 months: 0.82 [0.74 to 0.91]; at follow-up: 0.79 [0.69 to 0.99]) but not with graft loss.

CONCLUSIONS

Glomerular filtration rate recovery is a determinant of muscle mass variation after kidney transplantation. Early interventions targeting muscle mass gain may be beneficial for kidney transplant recipients.

Role of exosomes and exosomal microRNA in muscle–Kidney crosstalk in chronic kidney disease

Chronic kidney disease (CKD) is a progressive damage of kidneys that can no longer serve the blood-filtering function, and is a life-threatening condition. Skeletal muscle wasting is a common complication of CKD. Yet the relationship between kidney and skeletal muscle in CKD remains unclear. Exosomes, a type of small membrane-bound vesicles released from cells to the extracellular environment, have increasingly received attention due to their potential as mediators of crosstalk between kidneys and different organs, including skeletal muscle. This mini-review summarizes the recent findings that point to the role of exosomes in the cross-talk between kidney and skeletal muscle in CKD. Understanding of the contents and the mechanism of exosome release may prone exosomes be the potential therapeutic targets for CKD.

Pretransplant Psoas Muscle Cross-Sectional Area and Postkidney Transplant Outcomes

BACKGROUND

Sarcopenia is associated with adverse outcomes in end-stage kidney disease. We evaluated if pretransplant sarcopenia affects posttransplant outcomes in kidney transplant (KT) recipients.

METHODS

In this single-center retrospective study of adult patients with end-stage kidney disease, we analyzed the association between pre-KT psoas muscle cross-sectional area and critical posttransplant outcomes of decline in estimated glomerular filtration rate (eGFR), graft loss, rehospitalization, and mortality using Cox proportional hazard model adjusted for age, sex, and race.

RESULTS

Pre-KT abdomen and pelvic computed tomography scans performed during evaluation for KT eligibility were available for 573 KT recipients. Of these, 465 KT recipients received kidney alone transplant, 71 received simultaneous liver kidney transplant (SLK), and 37 received simultaneous pancreas kidney transplant (SPK). Patients were 49 (SD, 13) years old, 16% Black, and 60% men. For kidney alone transplant recipients, a higher psoas muscle cross-sectional area was associated with a shorter length of hospitalization (β coefficient = -0.003; 95% CI, -0.005 to -0.0007). Conversely, pre-KT psoas muscle cross-sectional area did not predict decline in eGFR, graft loss, mortality, or early rehospitalization. For SLK recipients, psoas muscle cross-sectional area did not predict any of the priori outcomes. For SPK recipients, higher pretransplant psoas muscle cross-sectional area predicted a longer length of hospitalization (β coefficient = 0.03; 95% CI, 0.01-0.05). There was no association between psoas muscle cross-sectional area and other outcomes assessed.

CONCLUSIONS

Pretransplant psoas muscle cross-sectional areas are not predictive of post-transplant decline in eGFR, graft loss, rehospitalization or mortality in kidney alone, SPK, or SLK transplants.

Effect of Sarcopenia on Mortality in Type 2 Diabetes: A Long-Term Follow-Up Propensity Score-Matched Diabetes Cohort Study

Purpose: The effect of sarcopenia on the survival of patients with type 2 diabetes remains unclear. Therefore, we designed a propensity score-matched population-based cohort study to compare the patients with diabetes with or without sarcopenia. Patients and Methods: We included patients with type 2 diabetes and categorized them into two groups according to whether they had sarcopenia and compared their survival; patients in the groups were matched at a ratio of 1:2. Results: The matching process yielded a final cohort of 201,698 patients (132,805 and 68,893 in the sarcopenia and nonsarcopenia diabetes groups, respectively) who were eligible for further analysis. According to both univariate and multivariate Cox regression analyses, the adjusted hazard ratios (aHRs; 95% confidence interval [CI]) of all-cause death for the sarcopenia diabetes group compared with the control group: 1.35 (1.33−1.38; p < 0.001). The aHRs (95% CIs) of all-cause death for those aged 41−50, 51−60, and >60 years (compared with those aged ≤40 years) were 1.53 (1.48−1.60), 2.61 (2.52−2.72), and 6.21 (5.99−6.45), respectively. The aHR (95% CI) of all-cause death for the male patients compared with the female patients was 1.56 (1.54−1.60). The aHRs (95% CIs) of all-cause death for those with adapted Diabetes Complications Severity Index (aDCSI) scores of 1, 2, 3, 4, and ≥5 (compared with an aDCSI score of 0) were 1.01 (1.00−1.14), 1.38 (1.35−1.42), 1.58 (1.54−1.63), and 2.23 (2.14−2.33), respectively. Conclusion: Patients with type 2 diabetes and sarcopenia had higher mortality than did those without sarcopenia.

Low serum creatinine to cystatin C ratio is independently associated with sarcopenia and high carotid plaque score in patients with type 2 diabetes

BACKGROUND AND AIMS

Low serum creatinine (Cr) to cystatin C (cysC) ratio has been suggested to be associated with low muscle mass and strength and poor prognosis in various chronic disease. We investigated the associations of CCR with sarcopenia and carotid plaque score (PS) in patients with type 2 diabetes mellitus.

METHODS AND RESULTS

A total of 1577 patients with type 2 diabetes were enrolled. High PS was defined as PS ≥ 3. Sarcopenia was assessed by the measurement of appendicular skeletal muscle mass (ASM) and grip strength (GS). Compared to the highest CCR group, the lowest tertile group was older; had higher C-reactive protein levels, CIMT, and PS, but lower cysC-based estimated glomerular filtration rate (cysC-eGFR), ASM/BMI, and GS. Positive correlations between CCR and ASM/BMI (r = 0.239 in men and 0.303 in women, p < 0.001) and GS (r = 0.282 in men and 0.270 in women, p < 0.001) were observed in both genders. Odds ratios and 95% confidence intervals for high PS after adjusting for age and sex were 1.22 (0.92-1.61, p = 0.18) in the middle and 1.74 (1.31-2.30, p < 0.001) in the lowest tertiles, respectively, with those of the lowest tertile remaining significant after further adjusting for multiple confounders.

CONCLUSIONS

Low CCR was independently associated with sarcopenia and high PS in patients with type 2 diabetes mellitus, especially after adjusting for ASM/BMI and GS.

Relationship between serum creatinine to cystatin C ratio and subclinical atherosclerosis in patients with type 2 diabetes

INTRODUCTION

Sarcopenia index (SI), calculated by (serum creatinine/cystatin C)×100, is reported to be associated with sarcopenia. Few studies reported the association between SI and subclinical atherosclerosis. We evaluated the association between SI and subclinical atherosclerosis, assessed by brachial-ankle pulse wave velocity (baPWV).

RESEARCH DESIGN AND METHODS

One hundred seventy-four patients with type 2 diabetes were included in this cross-sectional study. The relationship between SI and baPWV was assessed by Pearson's correlation coefficient. To calculate area under the receiver operator characteristic (ROC) curve (AUC) of SI for the presence of subclinical atherosclerosis, which was defined as baPWV >1800 cm/s, ROC analysis was performed. Logistic regression analyses were performed to assess the effect of SI on the prevalence of subclinical atherosclerosis adjusting for covariates.

RESULTS

Mean age, duration of diabetes, baPWV, and SI were 66.9 (10.1) years, 17.7 (11.6) years, 1802 (372) cm/s, and 77.6 (15.8), respectively. There was an association between SI and baPWV (men; r=-0.25, p=0.001, and women; r=-0.37, p=0.015). The optimal cut-off point of SI for the presence of subclinical atherosclerosis was 77.4 (sensitivity=0.72, specificity=0.58, p<0.001, AUC 0.66 (95% CI: 0.57 to 0.74)). In addition, SI was associated with the prevalence of subclinical atherosclerosis (adjusted OR 0.95, 95% CI: 0.91 to 0.99, p=0.015).

CONCLUSIONS

SI is associated with the prevalence of subclinical atherosclerosis in patients with type 2 diabetes.

Assessment of Muscle Quantity, Quality and Function

Sarcopenia is a syndrome characterized by loss of skeletal muscle mass and strength that can increase the risk of physical disability, chronic conditions such as diabetes mellitus and cardiovascular diseases, and long-term mortality. Sarcopenia adversely affects not only the elderly population, but also young adults. This review provides updated definitions of sarcopenia and recommendations for the assessment of muscle quantity and quality.

Relationship between psoas muscle index and long-term survival in older patients aged ≥ 80 years after endoscopic submucosal dissection for gastric cancer

BACKGROUND

In Japan, endoscopic submucosal dissection (ESD) has been widely performed for ESD-adapted gastric cancer, but little is known about the prognostic factors after ESD for gastric cancer in older patients. The psoas muscle index (PMI) is an indicator of sarcopenia calculated from computed tomography images and reportedly related to the prognosis of some diseases. This study aimed to explore factors related to long-term survival after ESD for gastric cancer in patients aged ≥ 80 years.

METHODS

We retrospectively reviewed 88 patients (63 men, 25 women) with early gastric cancer who underwent ESD at ≥ 80 years. Possible factors related to death after gastric ESD were analyzed by univariate and multivariate analyses using a Cox proportional hazards model. The estimated overall survival (OS) was compared between the groups stratified by significant factors.

RESULTS

The 5-year OS rate was 73.9% (median follow-up period, 5.4 years). In the multivariate analysis, a low PMI (< 6.36 in men, < 3.92 in women) (hazard ratio [HR] 2.89, 95% confidence interval [CI] 1.11-7.54) and high Charlson comorbidity index (CCI) (≥ 3) (HR 1.87, 95% CI 1.14-3.09) were independently related to death after ESD. The 5-year OS rates were significantly higher in the high PMI group (82.3% vs. 70.7%, P = 0.026) and the low CCI group (76.0% vs. 37.9%, P = 0.002).

CONCLUSION

In addition to low CCI, high PMI is a predictor of long-term survival after ESD for gastric cancer in patients aged ≥ 80 years.

Current status of the assessment of sarcopenia, frailty, physical performance and functional status in chronic kidney disease patients

PURPOSE OF REVIEW

Low physical function, frailty, and sarcopenia are common complications of chronic kidney disease (CKD). In this article, we review the epidemiology and pathogenesis of low physical function, as well as its associations with adverse outcomes in CKD patients. Additionally, we present various traditional and novel methods for assessment of physical function in CKD patients.

RECENT FINDINGS

In nondialysis dependent (NDD) and dialysis-dependent CKD patients, the prevalence of low physical function, frailty, and sarcopenia are substantially higher than in the general population. The potential mechanisms of low physical function, frailty, and sarcopenia in CKD patients are due to various factors including underlying kidney disease, co-existing comorbidities, and certain therapeutic interventions utilized in CKD. Increasing evidence has also uncovered the ill effects of impaired physical function on clinical outcomes in CKD patients.

SUMMARY

Routine assessment of physical function is an under-utilized yet important component in the management of CKD patients. Future studies are needed to determine how prescription of exercise and increased daily physical activity can be tailored to optimize the health and well-being of NDD and dialysis-dependent CKD patients in pursuit of successful aging.

Combined association of skeletal muscle mass and grip strength with cardiovascular diseases in patients with type 2 diabetes

BACKGROUND

Appendicular skeletal muscle mass (ASM) and grip strength (GS) have been suggested to be related to cardiovascular diseases (CVDs), but their association with type 2 diabetes (T2D) remains unclear. Therefore, we examined the combined association of ASM and GS with the prevalence of CVD in patients with T2D.

METHODS

A total of 1230 patients with T2D were recruited and divided into four groups based on the sex-specific median values of ASM adjusted for body mass index (ASM/BMI; short: SM) and GS: high SM/high GS (HSM/HGS), high SM/low GS (HSM/LGS), low SM/high GS (LSM/HGS), and low SM/low GS (LSM/LGS).

RESULTS

The LSM/LGS group was older and had higher values of systolic blood pressure, homeostasis model assessment of insulin resistance, waist circumference, and C-reactive protein but lower high-density lipoprotein cholesterol concentrations than the HSM/HGS group. After adjusting for potential confounders, the odds ratios (ORs) and 95% CIs for CVD, coronary heart disease (CHD), ischemic stroke, and peripheral arterial disease (PAD) in the LSM/LGS group were 2.90 (1.89-4.47), 2.39 (1.46-3.92), 1.77 (0.84-3.71), and 5.83 (1.58-21.48), respectively. After adjusting for variable confounders among patients with higher glycosylated hemoglobin (HbA1c) (≥7.1%), the ORs and 95% CIs for CVD and CHD in the LSM/LGS group were 7.27 (3.37-15.67) and 6.17 (2.65-14.37), respectively.

CONCLUSIONS

The combination of low SM and GS was strongly associated with CVD, CHD, and PAD in patients with T2D, especially in those with higher HbA1c levels.

Association between low skeletal muscle mass and subclinical coronary atherosclerosis in asymptomatic individuals evaluated by CT

AIM

To investigate the associations of skeletal muscle area and density with coronary atherosclerotic plaques and significant stenosis in asymptomatic adults.

MATERIALS AND METHODS

A total of 243 consecutive subjects who had voluntarily undergone abdominal unenhanced computed tomography (CT) and coronary CT angiography (CCTA) as part of a general health examination were investigated retrospectively. Skeletal muscle area index (SMI) and skeletal muscle density (SMD) was assessed using CT. Coronary atherosclerotic plaques and stenosis on CCTA were evaluated. The associations of low SMI and low SMD with coronary atherosclerotic plaques and significant stenosis were determined by logistic regression analysis.

RESULTS

After adjustment for cardiovascular risk factors, there were significant associations of low SMI or low SMD with atherosclerotic plaque, total significant stenosis, and significant stenosis caused by calcified or mixed plaques (for all p<0.05). In addition, multivariate regression analysis also showed that low SMI was independently associated with calcified plaque (p=0.038) and non-calcified plaque (p=0.006), and individuals with low SMD were more likely to have mixed plaque (p=0.001).

CONCLUSION

Assessment of the skeletal muscle on CT help to identify asymptomatic adults at risk for coronary atherosclerosis.

Preoperative sarcopenia and malnutrition are correlated with poor long-term survival after endovascular abdominal aortic aneurysm repair

PURPOSE

Sarcopenia and malnutrition are often used as surrogates for frailty, which is predictive of poor prognosis after surgery. We investigated the effects of sarcopenia and malnutrition on mortality after endovascular aneurysm repair (EVAR).

METHODS

The subjects of this study were patients who underwent EVAR at our hospital between June 2007 and December 2013, excluding those who underwent reintervention. The psoas muscle area at the L4 level was used as an indicator of sarcopenia. The Geriatric Nutritional Risk Index was used as an indicator of malnutrition.

RESULTS

There were 324 patients included in the study, with a mean age of 78.1 years and a median follow-up period of 56.7 months. Multivariate analysis revealed that sarcopenia (HR, 1.79; p = .042) and malnutrition (HR, 1.78; p = .043) were independent prognostic factors. Patients with both factors were classified as the high-risk group and others were classified as the low-risk group. The survival rate was significantly lower in the high-risk group than in the low-risk groups (p < .001). Even after propensity score matching, the high-risk group had a significantly lower survival rate (p < .001).

CONCLUSION

Both sarcopenia and malnutrition were associated with long-term mortality after EVAR. Patients with both indicators had a poor mid-term survival.

Serum indices based on creatinine and cystatin C predict mortality in patients with non-dialysis chronic kidney disease

Serum indices based on creatinine and cystatin C, including creatinine/cystatin C ratio (Cr/CysC), ratio and difference of estimated glomerular filtration rate (eGFR) based on cystatin C and creatinine (eGFRcys/eGFRcre and eGFR_Diff), and serum creatinine × eGFRcys, are recently identified serum markers for sarcopenia. We aimed to evaluate the association between these serum indices and mortality in patients with chronic kidney disease (CKD). A single-center retrospective cohort study included 1141 adult patients with stage 1–5 CKD between 2016 and 2018. Basic characteristics, comorbidities, laboratory parameters, and serum creatinine and cystatin C values were obtained. Patients were followed up until death, dialysis, transfer to another hospital, or end of the study. The median age (interquartile range) of our participants was 71 (62–81) years. During a median follow-up of 39 months, 116 (10.2%) patients died. Compared to the survivor group, Cr/CysC, eGFRcys/eGFRcre, eGFR_Diff, and Cr × eGFRcys were all lower in the non-survivors (p < 0.001 for all). The receiver operating characteristic curves of serum indices for predicting mortality showed that all four indices had significant discriminative power. Based on the Cox proportional hazard models, lower values of four serum indices, both as continuous and categorical variables, independently predicted mortality. Our findings suggest that low serum indices of Cr/CysC, eGFRcys/eGFRcre, eGFRDiff, and Cr × eGFRcys are independent indicators of mortality in patients with non-dialysis CKD.

Sarcopenia and Mortality in Patients With Chronic Non-dialytic Renal Disease: Systematic Review and Meta-Analysis

OBJECTIVE

To analyze the results of prospective studies on the presence of sarcopenia and its association with cardiovascular events and mortality in patients with non-dialysis-dependent chronic renal disease.

METHODS

This study used the PRISMA protocol for systematic review. The systematic review and meta-analysis protocol was recorded in the prospective record of systematic reviews by PROSPERO International: CRD42019120391.

DATA SOURCES

MEDLINE via PubMed, Embase, Cochrane Library, CINAHL, Scopus, Web of Science and LILACS from December 2018 to April 20, 2019, with the survey results updated in January 2021.

DATA ANALYSIS

Random effect models were calculated to compare the results due to high heterogeneity identified.

RESULTS

The survey identified 951 studies. Of these, 392 were removed by duplicates and 559 references were selected for analysis. In the stage of evaluating titles and abstracts, 555 articles were excluded because they did not include inclusion criteria related to the population and study design, leaving 4 articles that were included in the systematic review and meta-analysis. A meta-analysis identified that the presence of sarcopenia increased the risk of mortality by 143%.

CONCLUSION(S)

The meta-analysis identified the influence of sarcopenia on mortality in non-dialysis-dependent chronic renal disease.

Muscle-Bone Crosstalk in Chronic Kidney Disease: The Potential Modulatory Effects of Exercise

Chronic kidney disease (CKD) is a prevalent worldwide public burden that increasingly compromises overall health as the disease progresses. Two of the most negatively affected tissues are bone and skeletal muscle, with CKD negatively impacting their structure, function and activity, impairing the quality of life of these patients and contributing to morbidity and mortality. Whereas skeletal health in this population has conventionally been associated with bone and mineral disorders, sarcopenia has been observed to impact skeletal muscle health in CKD. Indeed, bone and muscle tissues are linked anatomically and physiologically, and together regulate functional and metabolic mechanisms. With the initial crosstalk between the skeleton and muscle proposed to explain bone formation through muscle contraction, it is now understood that this communication occurs through the interaction of myokines and osteokines, with the skeletal muscle secretome playing a pivotal role in the regulation of bone activity. Regular exercise has been reported to be beneficial to overall health. Also, the positive regulatory effect that exercise has been proposed to have on bone and muscle anatomical, functional, and metabolic activity has led to the proposal of regular physical exercise as a therapeutic strategy for muscle and bone-related disorders. The detection of bone- and muscle-derived cytokine secretion following physical exercise has strengthened the idea of a cross communication between these organs. Hence, this review presents an overview of the impact of CKD in bone and skeletal muscle, and narrates how these tissues intrinsically communicate with each other, with focus on the potential effect of exercise in the modulation of this intercommunication.

Utility of Ultrasound as a Valid and Accurate Diagnostic Tool for Sarcopenia: Sex-Specific Cutoff Values in Chronic Kidney Disease

OBJECTIVES

Patients with chronic kidney disease (CKD) have aberrant changes in body composition, including low skeletal muscle mass, a feature of "sarcopenia." The measurement of the (quadriceps) rectus femoris (RF) cross-sectional area (CSA) is widely used as a marker of muscle size. Cutoff values are needed to help discriminate the condition of an individual's muscle (eg, presence of sarcopenia) quickly and accurately. This could help distinguish those at greater risk and aid in targeted treatment programs.

METHODS

Transverse images of the RF were obtained by B-mode 2-dimensional ultrasound imaging. Sarcopenic levels of muscle mass were defined by established criteria (1, appendicular skeletal muscle mass [ASM]; 2, ASM/height² ; and 3, ASM/body mass index) based on the ASM and total muscle mass measured by a bioelectrical impedance analysis. The discriminative power of RF-CSA was assessed by receiver operating characteristic curves, and optimal cutoffs were determined by the maximum Youden index (J).

RESULTS

One hundred thirteen patients with CKD (mean age [SD], 62.0 [14.1] years; 48% male; estimated glomerular filtration rate, 38.0 [21.5] mL/min/1.73m² ) were included. The RF-CSA was a moderate predictor of ASM (R² = 0.426; P < .001) and total muscle mass (R² = 0.438; P < .001). With a maximum J of 0.47, in male patients, an RF-CSA cutoff of less than 8.9 cm² was deemed an appropriate cutoff for detecting sarcopenic muscle mass. In female patients, an RF-CSA cutoff of less than 5.7 cm² was calculated on the basis of ASM/height² (J = 0.71).

CONCLUSIONS

Ultrasound may provide a low-cost and simple means to diagnose sarcopenia in patients with CKD. This would allow for early management and timely intervention to help mitigate the effects in this group.

Association between the uremic toxins indoxyl-sulfate and p-cresyl-sulfate with sarcopenia and malnutrition in elderly patients with advanced chronic kidney disease

BACKGROUND

in patients with chronic kidney disease (CKD) indoxyl sulfate (IS) and p-cresyl sulfate (PCs) may induce sarcopenia either directly or via systemic inflammation. We evaluated whether IS and PCs were associated with: sarcopenia, systemic inflammation and nutritional status.

METHODS

we examined cross sectionally 93 patients with advanced CKD. Sarcopenia was identified according to EWGSOP2 definition. Malnutrition was assessed by Malnutrition Inflammation Score (MIS) and Protein Energy Wasting syndrome (PEW). Inflammatory status was assessed by dosing: CRP, IL6, TNFα, MCP1, IL10, IL17, IL12p70.

RESULTS

we did not find any association of sarcopenia with IS and PCs. IS was associated with LogTNFα and LogMCP-1 in the overall cohort (r = 0.30, p = 0.0043; r = 0.22 p = 0.047) and in not sarcopenic patients (r = 0.32, p = 0.0077; r = 0.25, p = 0.041). PCs was associated with LogIL10 and LogIL12p70 in sarcopenic patients (r = 0.58, p = 0.0042; r = 0.52, p = 0.013). IS was higher in patients without PEW (p = 0.029), while PCs was higher in patients with PEW (p = 0.0040). IS and PCs were not different in patients with normal or increased MIS.

CONCLUSIONS

IS and PCs were not associated with sarcopenia, although they were both associated with some inflammatory pathways. Notably, we found a positive association of PCs with PEW syndrome.

Physical Function in Kidney Transplantation: Current Knowledge and Future Directions

Purpose of review

Low physical function (PF) is common among individuals with end-stage kidney disease. In this review, we explore data on the impacts of PF on access to kidney transplantation (KT) and KT outcomes. We also discuss the latest interventions to improve PF in pre- and post-KT settings.

Recent Findings

Many US KT programs measure PF or related constructs when assessing KT candidacy. Although carefully selected KT candidates with low PF can benefit from KT with respect to survival and quality of life, low PF decreases the likelihood of being listed for KT and increases the risk of adverse post-KT outcomes. Recent trials suggest that exercise is a promising strategy to improve PF among KT candidates and recipients.

Summary

PF is a potentially modifiable risk factor for adverse pre- and post-KT outcomes. Research is needed to determine the ideal PF metric for use in KT evaluations and interventions to improve PF.

Sarcopenia Is Associated With a Risk of Mortality in People With Type 2 Diabetes Mellitus

BACKGROUND

Sarcopenia has reportedly been associated with increased risk of mortality in general populations. However, few studies have investigated the association between sarcopenia and mortality in older people with type 2 diabetes mellitus (T2D). This study aimed to investigate the effect of sarcopenia on incident all-cause mortality in older people with T2D.

METHODS

Low muscle strength were set at handgrip strength <28 kg for men and <18 kg for women, and low skeletal muscle mass index (SMI), evaluated using the impedance body composition analyzer, were set at SMI <7.0 kg/m² for men and <5.7 kg/m² for women. People who had both low muscle strength and low SMI were diagnosed with sarcopenia. Due to a low incidence of all-cause mortality, the propensity score was used. The propensity score was evaluated using multivariable logistic regression models with the following parameters: age, sex, duration of diabetes, history of heart disease, history of cancer, smoking, exercise, alcohol, sodium-glucose cotransporter-2 inhibitor, glucagon-like peptide-1 receptor agonist, insulin, corticosteroid, hypertension, body mass index, glycosylated hemoglobin A1c, triglycerides, and creatinine, and the C-statistic was 0.89.

RESULTS

In this prospective cohort study, 396 people with an average age and duration of diabetes of 71.3 (6.3) years and 16.3 (11.3) years, respectively, were included. Of those included, 14.6% had sarcopenia. During the average 40.5 (16.5) months of follow-up, 13 people (6 out of the 338 without sarcopenia and 7 out of the 58 with sarcopenia) died. Incident rate were 5.1/1000 person years of follow-up in people without sarcopenia and 41.3/1000 person years of follow-up in people with sarcopenia. According to Cox regression analysis, sarcopenia was associated with all-cause mortality (adjusted hazard ratio: 6.12, 95% confidence interval: 1.52-24.7, p = 0.011).

CONCLUSION

Sarcopenia is associated with incident all-cause mortality in older outpatients with T2D.

The Association between Major Dietary Pattern and Low Muscle Mass in Korean Middle-Aged and Elderly Populations: Based on the Korea National Health and Nutrition Examination Survey

Reduced skeletal muscle mass in older populations is independently associated with functional impairment and disability, resulting in increased risk of mortality and various comorbidities. This study aimed to examine the association between major dietary pattern and low muscle mass among Korean middle-aged and elderly populations. A total of 8136 participants aged ≥50 years were included from a cross-sectional study based on the 2008–2011 Korea National Health and Nutrition Examination Survey. The following four distinct dietary patterns were derived using factor analysis: “Condiment, vegetables, and meats”; “wheat flour, bread, fruits, milk, and dairy products”; “white rice, fish, and seaweeds”; and “whole grain, bean products, and kimchi”. A higher “white rice, fish, and seaweeds” pattern score was associated with a lower prevalence of low muscle mass in both men and women, whereas a higher “condiment, vegetables, and meats” pattern score was associated with a higher prevalence of low muscle mass in men. A dietary pattern based on white rice, fish, and seaweeds can be helpful in protecting against loss of skeletal muscle mass in Korean middle-aged and elderly populations. Future research is paramount to confirm the causal association between dietary pattern and the risk of low muscle mass.

Advanced Chronic Kidney Disease is a Strong Predictor of Hypogonadism and is Associated with Decreased Lean Tissue Mass

Purpose

In patients with chronic kidney disease (CKD), hypogonadism is more frequent than in the general population and its prevalence ranges between 40% and 60%. The aim of the study was to investigate the prevalence of hypogonadism and its association with kidney function, body composition, inflammatory markers and lipid disorders in patients with CKD.

Materials and Methods

The study population consisted of 112 men aged ≥40 years in different stages of CKD: 33 participants with eGFR ≥60 mL/min/1.73 m², 27 men with eGFR 30–59 mL/min/1.73 m², 17 predialysis patients with eGFR <30 mL/min/1.73 m², and 35 men on hemodialysis therapy three times a week for more than 3 months (G5D stage). Total testosterone (TT) levels were measured and free testosterone (FT) levels were calculated. Body composition was assessed using bioimpedance spectroscopy (Body Composition Monitor, FMC). Statistical analysis was performed using Statistica version 13.1.

Results

CKD stage was a strong predictor of hypogonadism (providing an information value of 0.83). The weight of evidence technique allowed us to differentiate the high-risk group, which was a group of patients with advanced CKD, defined as eGFR <30 mL/min/1.73 m². In this group, the likelihood of hypogonadism was 69.23%. Another significant predictor of hypogonadism was lean tissue index (LTI). TT and FT levels were significantly lower in the advanced CKD group in comparison to the control group, whereas prolactin, luteinizing hormone and C-reactive protein levels were significantly higher in the advanced CKD group. The LTI was significantly lower in advanced CKD and was positively correlated with TT and FT.

Conclusion

Decreased eGFR and decreased LTI are predictors of hypogonadism associated with CKD. The study results suggest that hypogonadism screening should be carried out when eGFR deceases below 30 mL/min/1.73 m².

Secondary sarcopenia assessed by computed tomography can predict hospitalization for heart failure in adults with Fontan circulation

BACKGROUND

Sarcopenia is one of the important predictors of heart failure (HF) in patients with cardiac problems. Skeletal muscle pump is important to maintain Fontan circulation. We aimed to quantify the volume of the psoas major muscle (PMM) and investigate whether it is relevant to HF hospitalization in adults with Fontan circulation.

METHODS

A total of 154 adults with Fontan circulation, and 30 age-matched adults were studied retrospectively. We identified secondary sarcopenia by measuring the PMM volume, using non-contrast abdominal computed tomography.

RESULTS

PMM indexed volume in Fontan patients was lower than controls (206.4+/-18.0 cc/m² vs 288.0+/-61.1 cc/m², p < 0.0001). In Fontan men, PMM indexed volume correlated with New York Heart Association functional class (NYHA FC). PMM indexed volume in Fontan women correlated with age, NYHA FC, and serum creatinine. Using a multivariate Cox hazards analysis, NYHA FC ≧3 was an important predictor of hospitalization due to HF in Fontan men. In Fontan women, NYHA FC ≧3, brain natriuretic peptide, PMM indexed volume, and protein losing enteropathy were important predictions of hospitalization due to HF. Among all Fontan patients, those with low PMM volumes had a poorer prognosis in HF [log rank p = 0.012 (men) and 0.0009 (women)].

CONCLUSIONS

PMM volume reduction has an adjunctive prediction of HF hospitalization in adults with Fontan circulation, particularly in Fontan females. Secondary sarcopenia may have a negative impact on the prognosis of HF in this population. The assessment of skeletal muscle mass also may be a comprehensive screening tool for multi-organ dysfunction in Fontan circulation.

Impact of sarcopenia in aortoiliac occlusive disease in Mediterranean population

BACKGROUND

This study aims to validate the psoas muscle area and psoas muscle density as morphometric predictors in cardiovascular and cerebrovascular endpoints in patients with extensive aortoiliac peripheral arterial disease.

METHODS

A total of 57 patients (55 males, 2 females; mean age 60±8.2 years; range, 35 to 83 years) with Trans-Atlantic Inter-Society Consensus type D lesions who underwent revascularization at two Portuguese tertiary hospitals between January 2013 and July 2019 were retrospectively analyzed. The patients with a recent (<6 months) computed tomography scan prior to the revascularization procedure were included in the study. Both centers offered to their patients open and endovascular repair of aortoiliac peripheral arterial disease. Major adverse cardiovascular and cerebrovascular events and major adverse limb events were evaluated.

RESULTS

The median follow-up was 20 months. The mean survival rate was 93±3.4% at 30 days and 62.7±8.6% at 48 months. The discriminative thresholds found in this population were 2,175.8 mm2 for total psoas area and 51.75 Hounsfield unit for psoas muscle density. There was a statistically significant difference in the one-year survival rate (p=0.003 and p=0.291, respectively) and major adverse cardiovascular and cerebrovascular events (p=0.005 and p=0.206, respectively) for total psoas area compared to psoas muscle density.

CONCLUSION

Total psoas area shows a prognostic value for survival and major adverse cardiovascular and cerebrovascular events in this patient population.

Long-Term Prognostic Predictors of Esophageal Squamous Cell Carcinoma Potentially Indicated for Endoscopic Submucosal Dissection

INTRODUCTION

Patients with esophageal squamous cell carcinoma (ESCC) have various comorbidities. Thus, it is necessary to determine the appropriateness of performing treatment based on the patient's general condition.

AIM

This study aimed to clarify the prognostic predictors of ESCC indicated for endoscopic submucosal dissection (ESD).

METHODS

This retrospective study enrolled 241 patients with superficial ESCC endoscopically diagnosed as ESD-indicated lesions at the Nagoya University Hospital between January 2007 and December 2017. We evaluated the 3- and 5-year overall survival (OS) rates and prognostic predictors, such as the Prognostic Nutritional Index (PNI), Charlson Comorbidity Index (CCI), Psoas Muscle Index, and Controlling Nutritional Status score. Furthermore, we created a score-based classification using the prognostic predictors identified by multivariate analysis, and the 3- and 5-year OS rates were compared among the calculated scores.

RESULTS

In the multivariate analysis, PNI < 45 (hazard ratio [HR]: 2.39; 95% confidence interval [CI]: 1.28-4.46; p = 0.006) and CCI ≥ 3 (HR: 4.42; 95% CI: 2.40-8.12; p < 0.001) were significantly associated with the OS. Based on the HR, 0 and 1 were assigned to PNI and 0, 2, and 4 were assigned to CCI, and the score classification of 0-5 points was created. The 3- and 5-year OS rates in patients with a score 3 were significantly higher than in those with scores 4 and 5. As a result of scoring, the prognosis was stratified; the 3- and 5-year OS rates in patients with scores 4 and 5, that is, CCI ≥ 6, were clearly low, at approximately 10%.

CONCLUSIONS

CCI and PNI can be prognostic predictors of patients with superficial ESCC indicated for ESD. Observation without ESD might be an acceptable strategy among patients with CCI ≥ 6.

Sarcopenia in chronic kidney disease: what have we learned so far?

The term sarcopenia was first introduced in 1988 by Irwin Rosenberg to define a condition of muscle loss that occurs in the elderly. Since then, a broader definition comprising not only loss of muscle mass, but also loss of muscle strength and low physical performance due to ageing or other conditions, was developed and published in consensus papers from geriatric societies. Sarcopenia was proposed to be diagnosed based on operational criteria using two components of muscle abnormalities, low muscle mass and low muscle function. This brought awareness of an important nutritional derangement with adverse outcomes for the overall health. In parallel, many studies in patients with chronic kidney disease (CKD) have shown that sarcopenia is a prevalent condition, mainly among patients with end stage kidney disease (ESKD) on hemodialysis (HD). In CKD, sarcopenia is not necessarily age-related as it occurs as a result of the accelerated protein catabolism from the disease and from the dialysis procedure per se combined with low energy and protein intakes. Observational studies showed that sarcopenia and especially low muscle strength is associated with worse clinical outcomes, including worse quality of life (QoL) and higher hospitalization and mortality rates. This review aims to discuss the differences in conceptual definition of sarcopenia in the elderly and in CKD, as well as to describe etiology of sarcopenia, prevalence, outcome, and interventions that attempted to reverse the loss of muscle mass, strength and mobility in CKD and ESKD patients.

Association between discharge destination and mid-term mortality in octogenarian patients with ST-elevation myocardial infarction

BACKGROUND

Owing to an increasing aging population, the number of elderly patients undergoing percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) is escalating. The onset of STEMI in elderly patients may lead to increased frailty, resulting in failure of discharge to home despite survival. However, the association of discharge destination with prognosis has not been fully evaluated in this population.

METHODS

Between January 2014 and December 2016, a total of 245 octogenarian STEMI survivors who underwent PCI (mean age, 84.4 years; male, 46.5%) were evaluated from a multicenter registry. The 2-year mortalities of the home discharge and non-home discharge groups were compared and analyzed using a Cox regression model.

RESULTS

Non-home discharge, which was defined as transfer to another hospital or nursing home after STEMI, was seen in 36 patients. During the 2 years, 37 patients died (home discharge, 27 patients; non-home discharge, 10 patients). The most frequent cause of death was due to infection (21.6%), followed by sudden death (18.9%) and heart failure (16.2%). The cumulative all-cause mortality was significantly higher in the non-home discharge group than in the home discharge group [36.4% vs. 14.8%; hazard ratio (HR), 2.95; 95% confidence interval (CI), 1.43-6.10; p = 0.003]. After multivariate analysis, non-home discharge (adjusted HR, 2.62; 95% CI, 1.20-5.75; p = 0.016) together with left ventricular ejection fraction <40% (adjusted HR, 3.15; 95% CI, 1.57-6.31; p = 0.001), prior heart failure (adjusted HR, 4.88; 95% CI, 1.82-13.13; p = 0.002), target lesion in the left anterior descending artery (adjusted HR, 2.20; 95% CI, 1.12-4.32; p = 0.022), and serum albumin level <3.5 g/dL (adjusted HR, 2.13; 95% CI, 1.06-4.27; p = 0.034) remained significant predictors of all-cause mortality.

CONCLUSION

Non-home discharge was associated with an increased risk of mid-term mortality in octogenarian STEMI survivors.

The association of muscle size, strength and exercise capacity with all-cause mortality in non-dialysis-dependent CKD patients

BACKGROUND/OBJECTIVE

Patients with chronic kidney disease (CKD) are commonly reported to exhibit skeletal muscle wasting, reduced strength and exercise capacity. Evidence from patients with end-stage renal disease (ESRD) demonstrates these factors are associated with mortality, but it is unclear whether this relationship exists earlier in the illness. Our objective was to determine whether muscle size, strength or exercise capacity was associated with all-cause mortality, unscheduled hospital admissions or time to ESRD in patients not requiring dialysis.

METHODS

This is a prospective cohort study of 89 patients with CKD stages 3b-5 not requiring renal replacement therapy with a mean follow-up period of 3.3 years in which the contribution of predictors of rectus femoris muscle size, muscle strength, exercise capacity to all-cause mortality rates, progression to ESRD and time to first hospitalization were investigated.

RESULTS

Unadjusted analysis suggested each 1 cm² increase in quadriceps muscle size (measured by ultrasonography cross-sectional area) was associated with a 38% reduced risk for death (p = .006), and a 10 m improvement on the incremental shuttle walk test was associated with a 3% reduced risk for death (p = .04). However, this relationship was not present in analysis adjusted for age, gender and eGFR. No association was seen between any factor for the development of ESRD or time to first hospitalization.

CONCLUSION

These results suggest that in this small cohort, muscle size and exercise capacity are associated with mortality when considered alone, but this relationship was not present in adjusted analyses. Further investigation in a larger patient group is warranted.

Creatinine/(cystatin C × body weight) ratio is associated with skeletal muscle mass index

We have previously reported that the creatinine (Cre) to cystatin C (CysC) ratio is associated with height-adjusted skeletal muscle mass index (SMI). However, weight-adjusted SMI is reported to be a more useful marker of insulin sensitivity than height-adjusted SMI. Thus, we hypothesized that the creatinine to (cystatin C × body weight [BW]) relationship (Cre/[CysC × BW]) might be associated with weight-adjusted SMI. In this cross-sectional study of 169 males and 132 females, a body composition analyzer was used and the weight-adjusted SMI was calculated as (absolute muscle mass [kg]/BW [kg]) × 100. The cut-off of low muscle mass was defined as weight-adjusted SMI <37.0% for males and <28.0% for females. The Cre/(CysC × BW) was correlated with weight-adjusted SMI in both males (r = 0.484, p < 0.001) and females (r = 0.538, p < 0.001). In addition, Cre/(CysC × BW) was associated with weight-adjusted SMI in both males (standardized β = 0.493, p < 0.001) and females (standardized β = 0.570, p < 0.001) after adjusting for covariates. According to the receiver operator characteristic (ROC) curve analysis, the optimal cut-off point of Cre/(CysC × BW) for low muscle mass was 0.0145 (area under the ROC curve [AUC] 0.756 [95% confidence interval {95% CI} 0.644-0.842], sensitivity = 0.96, specificity = 0.47, p < 0.001) in males and 0.0090 (AUC 0.976 [95% CI 0.894-0.995], sensitivity = 1.00, specificity = 0.93, p < 0.001) in females. There is a correlation between Cre/(CysC × BW) and weight-adjusted SMI. The Cre/(CysC × BW) could be a practical screening marker for low muscle mass.

Risk of Psoas Muscle Atrophy After Endovascular Aneurysm Repair Assessed by Cross-Sectional Psoas Muscle Area

PURPOSE

We evaluated possible association of decreased psoas muscle area (PMA) after endovascular aneurysm repair (EVAR) by measuring the area of muscle in computed tomographic (CT) images.

MATERIALS AND METHODS

We retrospectively reviewed CT images of 201 consecutive patients who underwent EVAR at our institution between April 1, 2015, and November 9, 2018, and compared them with images of 75 consecutive patients with no history of EVAR, who served as controls and underwent thoracic endovascular aortic repair (TEVAR) during the same period. We investigated EVAR and possible associated factors that might be potential predictors of decrease in PMA.

RESULTS

Those patients with a history of EVAR demonstrated significantly greater mean decrease in PMA than those with a history of TEVAR after the repair procedure (mean 6.25% (8.5); P < 0.001; odds ratio [OR], 3.63; 95% confidence interval [CI] 1.90-6.90).

CONCLUSION

Although EVAR is a less stressful procedure than other major abdominal surgeries, we identified it as an independent predictor of decreased area of the psoas muscle. Thus, our results might encourage post-procedural evaluation of frailty associated with psoas muscle function and prescription of appropriate rehabilitation interventions after EVAR to help prevent deterioration of patients' abilities.

Relationship Between Low Handgrip Strength and Chronic Kidney Disease: KNHANES 2014-2017

OBJECTIVE

Accelerated loss of muscle mass is common in patients with chronic kidney disease (CKD). Various factors associated with CKD, such as nutritional deficiencies, metabolic acidosis, and chronic inflammation, contribute to muscle wasting. This study aimed to investigate the relationship between CKD and handgrip strength (HGS) in the Korean population.

DESIGN AND METHODS

This is a population-based, cross-sectional study of a nationally representative sample of 18,765 patients aged ≥19 years from the Korea National Health and Nutrition Examination Survey in 2014-2017. We measured HGS using a digital hand dynamometer and determined the cutoff for low HGS by deriving -2 standard deviation values of sex-matched healthy young adults (19-39 years old). We defined CKD as eGFR <60 mL/min/1.73 m² or the presence of CKD based on a self-reported questionnaire.

RESULTS

The prevalence of CKD was 4.0% in the total population. The cutoff values for the low HGS were 29.5 kg for men and 16.8 kg for women. The prevalence of low HGS was 6.2% in patients without CKD, and 25.2% in patients with CKD. There was a significant correlation between HGS and eGFR in both men and women. In multivariate logistic regression adjusted by age group, diabetes, hypertension, and obesity, CKD showed an independent relationship with low HGS in both men (odds ratio [OR] 1.910, 95% confidence interval [CI] 1.468-2.485) and women (OR 1.570, 95% CI 1.202-2.052).

CONCLUSIONS

The prevalence of low HGS was higher in patients with CKD. We suggest that the sarcopenia should be evaluated in patients with CKD.

Hyperlipidemia and Statins Use for the Risk of New Diagnosed Sarcopenia in Patients with Chronic Kidney: A Population-Based Study

Background: Previous research found that statins, in addition to its efficiency in treating hyperlipidemia, may also incur adverse drug reactions, which mainly include myopathies and abnormalities in liver function. Aim: This study aims to assess the risk for newly onset sarcopenia among patients with chronic kidney disease using statins. Material and Method: In a nationwide retrospective population-based cohort study, 75,637 clinically confirmed cases of chronic kidney disease between 1997 and 2011were selected from the National Health Insurance Research Database of Taiwan. The selection of the chronic kidney disease cohort included a discharge diagnosis with chronic kidney disease or more than 3 outpatient visits with the diagnosis of chronic kidney disease found within 1 year. After consideration of patient exclusions, we finally got a total number of 67,001 cases of chronic kidney disease in the study. The Cox proportional hazards model was used to perform preliminary analysis on the effect of statins usage on the occurrence of newly diagnosed sarcopenia; the Cox proportional hazards model with time-dependent covariates was conducted to take into consideration the individual temporal differences in medication usage, and calculated the hazard ratio (HR) and 95% confidence interval after controlling for gender, age, income, and urbanization. Results: Our main findings indicated that patients with chronic kidney disease who use statins seem to effectively prevent patients from occurrences of sarcopenia, high dosage of statins seem to show more significant protective effects, and the results are similar over long-term follow-up. In addition, the risk for newly diagnosed sarcopenia among patients with lipophilic statins treatment was lower than that among patients with hydrophilic statins treatment. Conclusion: It seems that patients with chronic kidney disease could receive statin treatment to reduce the occurrence of newly diagnosed sarcopenia. Additionally, a higher dosage of statins could reduce the incidence of newly diagnosed sarcopenia in patients with chronic kidney disease.

Indoxyl Sulfate Contributes to Uremic Sarcopenia by Inducing Apoptosis in Myoblasts

OBJETIVE

Uremic sarcopenia is a complication of chronic kidney disease, particularly in its later stages, which leads to musculoskeletal disability. Uremic toxins have been linked to the pathogenesis of several manifestations of uremic syndrome. We sought to investigate whether indoxyl sulphate (IS), a protein-bound uremic toxin, is implicated in the development of uremic sarcopenia.

MATERIAL AND METHODS

Myoblasts were exposed to IS at normal (0.6 mg/L, IS_0.6), uremic (53 mg/L, IS₅₃) or maximum uremic (236 mg/L, IS₂₃₆) concentrations for 24, 48 and 72 h. Cell viability was evaluated by MTT assay and by 7-aminoactinomycin D staining. ROS generation and apoptosis were evaluated by flow cytometry. MyoD and myogenin mRNA expression was evaluated by qRT-PCR and myosin heavy chain expression by immunocytochemistry.

RESULTS

Myoblast viability was reduced by IS236 in a time-dependent pattern (p <0.05; 84.4, 68.0, and 63.6%). ROS production was significantly higher (p <0.05) in cells exposed to IS₅₃ and IS₂₃₆ compared to control (untreated cells). The apoptosis rate was significantly higher in cells treated with IS₅₃ and IS₂₃₆ than in control after 48h (p <0.05; 4.7 ± 0.1% and 4.6 ± 0.3% vs. 3.1 ± 0.1%, respectively) and 72h (p <0.05; 9.6 ± 1.1% and 10.4 ± 0.3% vs. 3.1 ± 0.7%, respectively). No effect was observed on MyoD, myogenin, myosin heavy chain expression, and markers of myoblast differentiation at any IS concentration tested or time-point experiment.

CONCLUSIONS

These data indicate that IS has direct toxic effects on myoblast by decreasing its viability and increasing cell apoptosis. IS may be a potential target for treating uremic sarcopenia.

Sarcopenia and myokines profile as risk factors in cardiovascular diseases?

Skeletal muscles and substances released during physical activity (myokines) have a beneficial influence on the functioning of the organism. Myokines (released also by myocardium) together with hepatokines and adipokines play an important role not only in energetic metabolism, but they also influence, among others, the function of the circulatory and nervous systems, modulation of inflammatory state and atherogenesis. Under pathological conditions connected with the presence of chronic diseases, chronic inflammatory state, low physical activity, long-term immobility the following consequences are observed: reduction of muscle mass and strength (sarcopenia) and changed profile of released myokines. The incidence of sarcopenia is connected with an unfavorable course of the aging process, often leading to disability and multiple morbidities. Sarcopenia can also lead to frailty syndrome, which not only worsens the prognosis of various diseases, but it can also increase the risk of medical procedures. Sarcopenia and adverse przymyokine profile are modifiable risk factors of cardiovascular diseases and affecting them may improve functional status and prognosis. An important intervention to improve muscles function and myokine profile, apart from nutritional treatment and pharmacotherapy, is regular physical activity as a component of cardiac rehabilitation. In our paper we focused on a review of the newest research regarding the association of sarcopenia and the profile of released myokines with incidence and course of cardiovascular diseases such as chronic heart failure, coronary artery disease, carotid artery atherosclerosis or ischemic cerebral stroke.

Skeletal muscle wasting in chronic kidney disease: the emerging role of microRNAs

Skeletal muscle wasting is a common complication of chronic kidney disease (CKD), characterized by the loss of muscle mass, strength and function, which significantly increases the risk of morbidity and mortality in this population. Numerous complications associated with declining renal function and lifestyle activate catabolic pathways and impair muscle regeneration, resulting in substantial protein wasting. Evidence suggests that increasing skeletal muscle mass improves outcomes in CKD, making this a clinically important research focus. Despite extensive research, the pathogenesis of skeletal muscle wasting is not completely understood. It is widely recognized that microRNAs (miRNAs), a family of short non-coding RNAs, are pivotal in the regulation of skeletal muscle homoeostasis, with significant roles in regulating muscle growth, regeneration and metabolism. The abnormal expression of miRNAs in skeletal muscle during disease has been well described in cellular and animal models of muscle atrophy, and in recent years, the involvement of miRNAs in the regulation of muscle atrophy in CKD has been demonstrated. As this exciting field evolves, there is emerging evidence for the involvement of miRNAs in a beneficial crosstalk system between skeletal muscle and other organs that may potentially limit the progression of CKD. In this article, we describe the pathophysiological mechanisms of muscle wasting and explore the contribution of miRNAs to the development of muscle wasting in CKD. We also discuss advances in our understanding of miRNAs in muscle–organ crosstalk and summarize miRNA-based therapeutics currently in clinical trials.

Exercise benefits in cardiovascular disease: beyond attenuation of traditional risk factors

Despite strong scientific evidence supporting the benefits of regular exercise for the prevention and management of cardiovascular disease (CVD), physical inactivity is highly prevalent worldwide. In addition to merely changing well-known risk factors for systemic CVD, regular exercise can also improve cardiovascular health through non-traditional mechanisms. Understanding the pathways through which exercise influences different physiological systems is important and might yield new therapeutic strategies to target pathophysiological mechanisms in CVD. This Review includes a critical discussion of how regular exercise can have antiatherogenic effects in the vasculature, improve autonomic balance (thereby reducing the risk of malignant arrhythmias), and induce cardioprotection against ischaemia-reperfusion injury, independent of effects on traditional CVD risk factors. This Review also describes how exercise promotes a healthy anti-inflammatory milieu (largely through the release of muscle-derived myokines), stimulates myocardial regeneration, and ameliorates age-related loss of muscle mass and strength, a frequently overlooked non-traditional CVD risk factor. Finally, we discuss how the benefits of exercise might also occur via promotion of a healthy gut microbiota. We argue, therefore, that a holistic view of all body systems is necessary and useful when analysing the role of exercise in cardiovascular health.

Ultrasound assessment of muscle mass in response to exercise training in chronic kidney disease: a comparison with MRI

BACKGROUND

Chronic kidney disease (CKD) is a catabolic condition associated with muscle wasting and dysfunction, which associates with morbidity and mortality. There is a need for simple techniques capable of monitoring changes in muscle size with disease progression and in response to interventions aiming to increase muscle mass and function. Ultrasound is one such technique; however, it is unknown how well changes in muscle cross-sectional area (CSA) measured using ultrasound relate to changes in whole muscle volume measured using magnetic resonance imaging. We tested whether rectus femoris CSA (RF-CSA) could be used as a valid indication of changes in quadriceps muscle volume as a single measure of muscle size and following a 12 week exercise intervention that resulted in muscle hypertrophy.

METHODS

Secondary analysis of data was collected from the ExTra CKD study (ISRCTN 36489137). Quadriceps muscle size was assessed from 36 patients with non-dialysis CKD before and after 12 weeks of supervised exercise that resulted in muscle hypertrophy.

RESULTS

Strong positive correlations were observed between RF-CSA and quadriceps volume at baseline (r² = 0.815, CI 0.661 to 0.903; P < 0.001) and following 12 week exercise (r² = 0.845, CI 0.700 to 0.923; P < 0.001). A moderate positive association was also observed between changes in RF-CSA and quadriceps following exercise training (rho = 0.441, CI 0.085 to 0.697; P = 0.015). Bland-Altman analysis revealed a small bias (bias 0.6% ± 12.5) between the mean percentage changes in RF-CSA and quadriceps volume but wide limits of agreement from -24 to 25.

CONCLUSIONS

Rectus femoris CSA appears to be a reliable index of total quadriceps volume as a simple measure of muscle size, both as a single observation and in response to exercise training in non-dialysis CKD patients.

Body composition and arterial stiffness in pediatric patients with chronic kidney disease

BACKGROUND

This study investigated the impact of body composition in the arterial stiffness of children with chronic kidney disease (CKD).

METHODS

Fat mass (FM), fat tissue index (FTI), fat-free mass (FFM), fat-free tissue index (FFTI), and FFTI/FTI were measured in 26 patients and 25 healthy controls by bio-impedance analysis. Data on patient's body mass index (BMI) for height-age, serum albumin, glomerular filtration rate (GFR), blood pressure status, and pulse wave velocity (PWV) were collected in patients.

RESULTS

Patients presented lower levels of FM and FFM compared to healthy controls (p = 0.04 and p = 0.055 respectively). In patient group, BMI height-age z-score was positively correlated to FTI (r² = 0.574, p < 0.001) and FFTI (r² = 0.338, p = 0.001) and negatively correlated to FFTI/FTI (r² = 0.263, p = 0.007). Serum albumin was positively correlated only with FFM among body composition data (r² = 0.169, p = 0.037). PWV z-score was positively correlated to FFTI (r² = 0.421, p = 0.006) and inversely correlated to FFTI/FTI ≥ 2.5 (r² = 0.317, p = 0.003). Patients with FFTI/FTI ≥ 2.5 presented lower levels of PWV regardless the need for antihypertensive treatment. Serum albumin ≥ 3.8 mg/dl and FFTI/FTI ≥ 2.5 were independently associated with a lower risk for high PWV, after adjustment for age, sex, and GFR (OR 0.009, 95% CI 0.000-0.729 and OR 0.039, 95% CI 0.002-0.680). All underweight [2 (7.7%)] and overweight [4 (15.4%)] patients presented high PWV. Among normal weight patients, FFTI/FTI ratio ≥ 2.5 was significantly associated with lower PWV z-score (p = 0.013).

CONCLUSIONS

Both underweight and overweight are associated with arterial stiffness. Targeting FFTI/FTI ≥ 2.5 could be protective against cardiovascular disease in normal weight children.

Muscle changes with high-intensity aerobic training in an animal model of renal disease

Purpose:

To analyze the muscle changes with high-intensity aerobic training (HIAT) in an animal model of renal disease (RD).

Methods:

Twenty one adult Wistar rats were divided into 3 groups: healthy sedentary (HS), RD sedentary (RDS), RD aerobic training (RDAT). RDS and RDAT were subjected to unilateral renal ischemia-reperfusion (10 min) and 21days after that, RDAT was subjected to 6 weeks HIAT (swimming). Serum creatinine (Cr) and muscle morphometry (cross-sectional area = CSA) of gastrocnemius were analyzed.

Results:

Cr was higher (p = 0.0053) in RDS (0.82 ± 0.04) than in the others (RDAT 0.55 ± 0.04; HS 0.55 ± 0.04). Morphometric analysis (class interval of CSA in μm²/absolute frequency of muscle fibers in each class) indicated that 50th percentile occurred in: HS 7th class (3000.00-3499.00/515), RDS, 8th class (3500.00-3999.00/484), RDAT 5th class (2000.00-2499.00/856). CSA of largest fibers in RDS, RDAT, HS was 9953.00 μm², 9969.00 μm²,11228.00 μm², respectively. High frequency of fibers with lower CSA occurred in 4th, 5th, 6th and 7th class in RDA, absence of fibers into 22nd, 23rd classes (RDS and RDAT).

Conclusion:

HIAT in an animal model of RD resulted in increased the number of muscle fibers with smaller CSA.

The Differential Association between Muscle Strength and Diabetes Mellitus According to the Presence or Absence of Obesity

Background

Muscle strength can be affected by body mass index. In the present study, we compared the association between the diabetes mellitus (DM) and muscle strength according to obesity.

Methods

We analyzed the association between DM and muscle strength using the Korea National Health and Nutrition Examination Survey 2014 to 2016 data weighted to represent the Korean population aged between 30 and 79 years old. Muscle strength was classified into age- and sex-specific quartiles (Qs) of handgrip strength, with the lowest Q defined as “low muscle strength (LMS).”

Results

Muscle strength was positively associated with body mass index in both sexes (P<0.001); the prevalence of obesity increased by 30% in male (odds ratio [OR], 1.300; 95% confidence interval [CI], 1.231–1.373) and 12% in female (OR, 1.122; 95% CI, 1.062–1.185), respectively, per one Q of muscle strength. In contrast, the prevalence of DM decreased as muscle strength increased (OR per one Q, 0.926; 95% CI, 0.862–0.996 in male and OR per one Q, 0.917; 95% CI, 0.854–0.986 in female). LMS was significantly associated with DM even following adjustment for age, sex, family history of DM, abdominal obesity, dyslipidemia, and hypertension (OR, 1.328; 95% CI, 1.133–1.558). Stratified analysis according to obesity status showed that it remained significant only in nonobese populations (OR, 1.513; 95% CI, 1.224–1.870 in nonobese participants and OR, 1.124; 95% CI, 0.879–1.437 in obese participants).

Conclusion

LMS was independently associated with DM in the Korean population aged between 30 and 79 years. However, obesity-stratified analysis revealed that it was significant only in the nonobese population.

Low Skeletal Muscle Mass Independently Predicts Mortality in Patients with Chronic Heart Failure after an Acute Hospitalization

BACKGROUND

Heart failure (HF) is a syndrome associated with exercise intolerance, and its symptoms are more common in patients with low skeletal muscle mass (SMM). Estimation of muscle mass can be cumbersome and unreliable, particularly in patients with varying body weight. The psoas muscle area (PMA) can be used as a surrogate of sarcopenia and has been associated with poor outcomes in other populations.

OBJECTIVES

The aim of this study was to assess if sarcopenia is associated with the survival of patients with HF after an acute hospitalization.

METHOD

We retrospectively studied a cohort of 160 patients with HF who had abdominopelvic computed tomography during an acute hospitalization. We obtained standardized measurements of their PMA and defined sarcopenia as the lowest gender-based tertile of the said area. The patients were followed until death or discontinuation of care. We used Kaplan-Meier estimates and Cox regression analysis to assess the relationship between sarcopenia and all-cause mortality.

RESULTS

We found that the 52 patients with sarcopenia had 4.5 times the risk of all-cause mortality at 1 year compared to the rest of the cohort (CI 1.784-11.765; p = 0.0016) after adjusting for significant covariates. Stratification by age and sex revealed that this association could be limited to males and patients < 75 years old.

CONCLUSION

The PMA, used as a surrogate of low SMM, is independently associated with an increased risk of late mortality after an acute hospitalization in patients with HF.

Trimetazidine combined with exercise improves exercise capacity and anti-fatal stress ability through enhancing mitochondrial quality control

AIMS

To explore the effects of trimetazidine combined with exercise on EC and anti-fatal stress ability, and illustrate the underlying mechanism.

METHODS

C57BL/6 mice were randomly assigned to four groups (n = 11 in each group): the control, exercise, trimetazidine and trimetazidine + exercise (TE) groups. Mice were accordingly given saline (ig), Aerobic exercise (AE), trimetazidine (ig), or a combination of trimetazidine (ig) and AE for five weeks. After the intervention, each group was randomly subdivided into rest and exhaustive exercise (EE) subgroups. The mice in the control-EE and TE-EE subgroups underwent fatal stress experiments. EC and anti-fatal stress ability were assessed respectively. Mitochondrial quality control (MQC) in skeletal muscle were measured at the protein level and the organelle level.

KEY FINDINGS

A significantly increased exhaustive swimming time was observed in exercise (39.10 ± 12.58 min vs 14.18 ± 4.37 min), trimetazidine (33.73 ± 8.45 min vs 14.18 ± 4.37 min) and TE groups (73.78 ± 18.95 min vs 14.18 ± 4.37 min) compared with that in the control group, and a synergistic effect was detected (P < 0.05). Fatal stress experiments successfully induced skeletal muscle damage, including increased creatine kinase activity, myofibrosis, and impaired antioxidative enzyme system, all those were significantly alleviated by trimetazidine supplementation combined with AE precondition (P < 0.05). Meanwhile, AE and trimetazidine alone or combined, significantly enhanced the MQC in normal mice by activating mitochondrial biogenesis, dynamics and mitophagy, and that in mice underwent fatal stress stimulus (P < 0.05).

SIGNIFICANCE

This study for the first time found that trimetazidine and AE have synergistic effects on improving EC. Moreover, the combination of both interventions enhances anti-fatal stress ability. Enhancing MQC may be a key mechanism of AE combined with trimetazidine that improves EC and anti-fatal stress ability.

Satellite cell function, intramuscular inflammation and exercise in chronic kidney disease

Skeletal muscle wasting is a common feature of chronic kidney disease (CKD) and is clinically relevant due to associations with quality of life, physical functioning, mortality and a number of comorbidities. Satellite cells (SCs) are a population of skeletal muscle progenitor cells responsible for accrual and maintenance of muscle mass by providing new nuclei to myofibres. Recent evidence from animal models and human studies indicates CKD may negatively affect SC abundance and function in response to stimuli such as exercise and damage. The aim of this review is to collate recent literature on the effect of CKD on SCs, with a particular focus on the myogenic response to exercise in this population. Exercise is widely recognized as important for the maintenance of healthy skeletal muscle mass and is increasingly advocated in the care of a number of chronic conditions. Therefore a greater understanding of the impact of uraemia upon SCs and the possible altered myogenic response in CKD is required to inform strategies to prevent uraemic cachexia.

Rectus femoris muscle mass evaluation by ultrasound: facilitating sarcopenia diagnosis in pre-dialysis chronic kidney disease stages

OBJECTIVES

We evaluated the validity and reliability of ultrasonography measurement of rectus femoris cross-sectional area compared to computed tomography in patients in pre-dialysis chronic kidney disease and analyzed the association between these measurements and the diagnosis of sarcopenia.

METHODS

One hundred patients with nondialysis chronic kidney disease were evaluated. Sarcopenia was defined using the criteria of the Foundation for the National Institutes of Health Sarcopenia Project (FNIH). The rectus femoris cross-sectional area was evaluated using ultrasonography and computed tomography.

RESULTS

The prevalence of sarcopenia was 29% according to the FNIH criteria. The difference in mean rectus femoris cross-sectional area by ultrasonography and computed tomography was 3.97 mm, with a strong correlation between the two methods (p<0.001). Bland-Altman plot analysis showed good agreement between computed tomography and ultrasonography. Rectus femoris cross-sectional area was significantly correlated with muscle strength (r=0.300, p=0.002), lean body mass in the upper limbs (r=0.286, p=0.004), and lean body mass in the lower limbs (r=0.271, p=0.006). The prevalence of sarcopenia was 12% (n=12) based on the definition of low muscle mass according to ultrasonography of the rectus femoris cross-sectional area.

CONCLUSION

Ultrasonography was demonstrated to be a valid and reliable method for evaluating the rectus femoris cross-sectional area in patients in pre-dialysis chronic kidney disease.