Sarcopenia and Frailty in PD: Impact on Mortality, Malnutrition, and Inflammation

Association of interleukin-6 with sarcopenia and its components in older adults: a systematic review and meta-analysis of cross-sectional studies

BACKGROUND

Observational studies have documented increased serum IL-6 levels in elderly individuals afflicted with sarcopenia. Nevertheless, the relationship between serum IL-6 concentrations and sarcopenia prevalence in the aging population is yet to be defined.

METHODS

We executed a systematic review and meta-analysis of cross-sectional studies that scrutinized serum IL-6 levels in older adults with and without sarcopenia. Relevant studies were sourced from PubMed, Scopus, Embase, Cochrane Library, and Web of Science from inception until 10 September 2023. The standard mean differences (SMDs) in serum IL-6 levels between studies were synthesized using a random-effects model. To examine the influence of demographic and clinical factors on these outcomes, we performed subgroup analyses and meta-regression, focusing on variables such as sex, age, and body mass index (BMI). We also assessed the relationship between serum IL-6 levels and the defining components of sarcopenia: muscle mass, muscle strength, and physical performance. We used Fisher's Z transformation to standardize the interpretation of effect sizes from these relationships. The transformed values were then converted to summary correlation coefficients (r) for a clear and unified summary of the results.

RESULTS

We included twenty-one cross-sectional studies involving 3,902 participants. Meta-analysis revealed significantly elevated serum IL-6 levels in older adults with sarcopenia compared with those without sarcopenia (SMD = 0.31; 95% CI 0.18, 0.44). The difference was highly pronounced in the subgroups of male and those with female percentage below 50% or a mean BMI below 24 kg/m2. Serum IL-6 levels were inversely correlated with muscle mass (summary r = -0.18; 95% CI -0.30, -0.06), but not with handgrip strength (summary r = -0.10; 95%CI: -0.25, 0.05) or gait speed (summary r = -0.09; 95%CI: -0.24, 0.07).

CONCLUSIONS

This meta-analysis establishes a link between increased serum IL-6 levels and sarcopenia in the elderly, particularly in relation to decreased muscle mass.

Impact of compliance with salt management guidelines before dialysis introduction on peritoneal dialysis technique survival: The importance of pre-dialysis care and education

INTRODUCTION

Peritoneal dialysis (PD) is a mode of therapy in which the patients themselves actively participate in the care of their own disease. We examined a possible association of salt reduction before starting dialysis with PD technique survival.

METHODS

This retrospective cohort study included 42 patients who started PD between April 2014 and March 2018. Participants were allocated to two groups based on their estimated daily salt intake before the initiation of dialysis: patients with an estimated daily salt intake <6 g/day were allocated to the appropriate salt intake group (AS group), while the rest were assigned to the high salt intake group (HS group).

RESULTS

During a median follow-up of 47 months, PD technique survival, defined by death or transition to hemodialysis, was significantly lower in the HS group compared to the AS group.

CONCLUSION

Successful salt reduction before dialysis introduction is associated with better PD technique survival.

Comorbid Hypothyroidism and Low-Alanine Aminotransferase-Associated Sarcopenia Associated with Shortened Survival: A Retrospective Study of 16,827 Patients over a 21-Year Period

Background: Hypothyroidism is very common worldwide. It is known to be associated with frailty which, in turn, is associated with increased morbidity and mortality in the elderly. Low ALT blood activity is an established marker for sarcopenia and frailty. The incidence and outcomes of the association between low ALT values and hypothyroidism, as manifested in elevated blood TSH levels, is unknown. The objective of this study was to assess if low ALT values could improve the prediction of clinical outcome in hypothyroid patients. Methods: This was a retrospective analysis of hospitalized patients in a large, tertiary hospital. Results: Over a period of 21 years, an overall population of 16,827 patients were identified as eligible to participate in this study. Within the study population, 726 (4.3%) were classified as suffering from hypothyroidism (TSH values > 6 MIU/L) and 2184 (13%) were classified as patients with sarcopenia (ALT < 12 IU/L). Within our patient population, hypothyroidism was associated with sarcopenia in a statistically significant manner (p = 0.011). Patients classified as suffering from both hypothyroidism and sarcopenia had significantly shorter survival: A multivariate analysis showed that the frail and hypothyroid group of patients had a statistically significant risk of mortality in the next 5 years (HR = 3.6; CI 2.75-4.71; p < 0.001). Conclusions: Sarcopenia and frailty are common comorbidities, bearing negative long-term clinical outcomes. Low ALT values could serve as a useful biomarker for screening of patients already diagnosed with hypothyroidism.

Sarcopenia is associated with survival in patients awaiting kidney transplant

BACKGROUND

The relationship of sarcopenia to frailty and other survival determinants in patients waitlisted for kidney transplant is not well characterized. Our goal was to evaluate the relationship of muscle area to functional and frailty metrics and its impact on survival in patients waitlisted for kidney transplant.

METHODS

Among 303 consecutively listed transplant candidates, 172 had a computed scan within 3 months of frailty and biochemical testing that permitted muscle area evaluation. Third lumbar level psoas muscle indices (total bilateral psoas area/height2) were calculated. Testing included frailty metrics, treadmill and pedometer ability, troponin, and brain natriuretic peptide levels. Associations between muscle area, demographic, biochemical, and frailty measures were analyzed. Log-rank test was used to evaluate waitlist survival on the basis of muscle area, and multivariate Cox proportional hazards modeling was used to evaluate factors independently associated with survival.

RESULTS

Demographic factors associated with third lumbar level psoas muscle indices include male sex (P < .001), race (P = .02), age (P = .004), and body mass index (P < .0001). Grip strength, treadmill ability, and Sit-Stands positively correlated with third lumbar level psoas muscle indices (P < .01). Brain natriuretic peptide and Up and Go negatively correlated with third lumbar level psoas muscle indices (P < .01). Survival was significantly associated with third lumbar level psoas muscle indices (P = 0.02). Treadmill ability, Sit-Stands, Up and Go, race and muscle area were most closely associated with waitlist survival on multivariate modeling.

CONCLUSION

Sarcopenia as assessed with muscle area measurements is independently associated with kidney waitlist survival. Functional ability and muscle area may be overlapping, but noncongruent, determinants of waitlist outcomes and may need to be individually assessed to create the most predictive survival model.

Exploring the impact of interleukins on sarcopenia development: A systematic review and meta-analysis

BACKGROUND

The role of interleukins in sarcopenia development has been acknowledged, yet the specifics of their involvement remain to be fully understood. This study aimed to explore alterations in interleukin levels among sarcopenia patients.

METHODS

Searches were conducted in Embase, Medline, and the Cochrane Library for literature published up to May 2023. Eligible observational studies with a diagnosis of sarcopenia were included. The Newcastle-Ottawa Scale was utilized for quality assessment. For data synthesis, a random-effects model was used, and the Mantel-Haenszel method was used for pooled estimates.

RESULTS

Of the 7685 articles screened, 37 met the inclusion criteria. Statistically significant differences in the levels of IL-1β, IL-6 and IL-10 were detected in sarcopenia patients. Specifically, IL-1β (95 % CI: 0.33 [0.12, 0.54], P < 0.05), IL-6 (95 % CI: 0.91 [0.59, 1.24], P < 0.05), and IL-10 (95 % CI: 0.11 [0.07,0.15], P < 0.05) were detected. However, no significant associations were found between serum IL-4 (95 % CI: 0.36 [-0.18, 0.42], P = 0.44), IL-8 (95 % CI: -1.05 [-3.06, 0.95], P = 0.3), IL-12 (95 % CI: -3.92 [-8.32,0.48], P = 0.08) or IL-17 (95 % CI: 0.22 [-2.43, 2.88], P = 0.87) and sarcopenia. Subgroup analysis showed no significant difference in IL-6 (95 % CI: -0.03 [-0.72, 0.66], P = 0.93) and IL-10 (95 % CI: 0.1 [-0.44, 0.64], P = 0.72) among patients with European standard sarcopenia.

CONCLUSIONS

Inflammation plays a role in sarcopenia, and the serum levels of IL-1β, IL-6, and IL-10 are associated with sarcopenia. Further research is needed to clarify these associations.

CLINICAL TRIALS REGISTRATION NUMBER

CRD42024506656.

A Prospective Cohort Study Evaluating Impact of Sarcopenia on Hospitalization in Patients on Continuous Ambulatory Peritoneal Dialysis

Data regarding the association of sarcopenia with hospitalization has led to inconclusive results in patients undergoing dialysis. The main goal of this research was to investigate the association between sarcopenia and hospitalization in Chinese individuals on continuous ambulatory peritoneal dialysis (CAPD). Eligible patients on CAPD were prospectively included, and followed up for 48 weeks in our PD center. Sarcopenia was identified utilizing the criteria set by the Asian Working Group on Sarcopenia in 2019 (AWGS 2019). Participants were categorized into sarcopenia (non-severe sarcopenia + severe sarcopenia) and non-sarcopenia groups. The primary outcome was all-cause hospitalization during the 48-week follow-up period. Association of sarcopenia with all-cause hospitalization was examined by employing multivariate logistic regression models. The risk of cumulative incidence of hospitalization in the 48-week follow-up was estimated using relative risk (RR and 95% CI). The cumulative hospitalization time and frequency at the end of 48-week follow-up were described as categorical variables, and compared by χ2 test or fisher's exact test as appropriate. Subgroup and sensitivity analyses were also conducted to examine whether the potential association between sarcopenia and hospitalization was modified. A total of 220 patients on CAPD (5 of whom were lost in follow-up) were included. Prevalences of total sarcopenia and severe sarcopenia were 54.1% (119/220) and 28.2% (62/220) according to AWGS 2019, respectively. A total of 113 (51.4%) participants were hospitalized during the 48-week follow-up period, of which, the sarcopenia group was 65.5% (78/119) and the non-sarcopenia group was 34.7% (35/101), with an estimated RR of 1.90 (95%CI 1.43-2.52). The cumulative hospitalization time and frequency between sarcopenia and non-sarcopenia groups were significantly different (both P < 0.001). Participants with sarcopenia (OR = 3.21, 95%CI 1.75-5.87, P < 0.001), non-severe sarcopenia (OR = 2.84, 95%CI 1.39-5.82, P = 0.004), and severe sarcopenia (OR = 3.66, 95%CI 1.68-8.00, P = 0.001) demonstrated a significant association with all-cause hospitalization compared to individuals in non-sarcopenia group in the 48-week follow-up. Moreover, participants in subgroups (male or female; < 60 or ≥ 60 years) diagnosed with sarcopenia, as per AWGS 2019, were at considerably high risk for hospitalization compared to those with non-sarcopenia. In sensitivity analyses, excluding participants lost in the follow-up, the relationships between sarcopenia and hospitalization (sarcopenia vs. non-sarcopenia; severe sarcopenia/non-severe sarcopenia vs. non-sarcopenia) were consistent. This research involving Chinese patients on CAPD demonstrated a significant association between sarcopenia and incident hospitalization, thereby emphasizing the importance of monitoring sarcopenia health in this population.

Frailty in Kidney Disease: A Comprehensive Review to Advance Its Clinical and Research Applications

Frailty is a multisystem syndrome of decreased physiologic reserve that has been shown to strongly and independently predict morbidity and mortality. Frailty is prevalent in patients living with kidney disease and occurs earlier in individuals with kidney disease as compared to the general population. In this comprehensive review, we examine clinical and research applications of frailty in kidney disease populations. Specifically, we clarify the definition of frailty and address common misconceptions, review the mechanisms and epidemiology of frailty in kidney disease, discuss challenges and limitations in frailty measurement, and provide updated evidence related to risk factors for frailty, its associated adverse outcomes, and interventions. We further add to the literature in this topic by highlighting the potential applications of frailty measurement in the care of patients with kidney disease and conclude with our recommendations for future research related to this important syndrome.

Physical exercise as a modulator of the purinergic system in the control of sarcopenia in individuals with chronic kidney disease on hemodialysis

The word sarcopenia derives from the Greek terms "sarx" for meat and "penia" for loss, thus being used to define reductions in muscle mass, muscle strength, and lower physical performance that compromise, mainly, the elderly population. Its high negative impact on patients' quality of life encourages the production and publication of new studies that seek to find methods to prevent and reverse cases of loss of muscle mass and strength. Furthermore, the high prevalence of sarcopenia in patients with chronic kidney disease (CKD) is closely related to its pathophysiology, which consists of a state of increased protein catabolism and decreased muscle tissue synthesis. Also considering the inflammatory nature of CKD and sarcopenia, the purinergic system has been an important target of studies, which seek to relate it to the two previous conditions. This system achieves anti-inflammatory action by inhibiting, through adenosine, pro-inflammatory factors such as interleukin-12 (IL-12), tumor necrosis factor alpha (TNF-α), and nitric oxide (NO), as well as by releasing anti-inflammatory substances such as interleukin-10 (IL-10). Simultaneously, the purinergic system presents pro-inflammatory activity, signaled by adenosine triphosphate (ATP), which occurs through the activation of T cells and the release of pro-inflammatory factors such as those mentioned above. Therefore, the ability of this system to act on inflammatory processes can promote positive and negative changes in the clinical aspect of patients with CKD and/or sarcopenia. Furthermore, it appears that there is a correlation between the practice of repeated physical exercise with the clinical improvement and in the quality of life of these patients, presenting a decrease in the levels of C-reactive protein (CRP), NTPDase, and the pro-inflammatory cytokine IL-6, such as increases in IL-10 resulting from modulation of the purinergic system. In this way, the present article seeks to evaluate the effect of physical exercise as a modulator of the purinergic system in the control of sarcopenia in patients with CKD on hemodialysis, in order to trace a relationship that can bring benefits both for biological markers and for quality of life of these patients.

FRAIL scale as a screening tool and a predictor of mortality in non-dialysis dependent patients

BACKGROUND

This study aimed to compare the diagnostic yield of the FRAIL scale with respect to the physical frailty phenotype measure and their association with mortality in non-dialysis-dependent patients.

METHODS

In this prospective cohort study, non-dialysis dependent patients with chronic kidney disease (CKD) stages 3b-5 seen in the nephrology outpatient clinics of two university hospitals were included. The presence of frailty was evaluated by physical frailty phenotype measure and the FRAIL scale. Patients were evaluated for six months, and mortality was recorded. The Kappa test was used to evaluate the diagnostic properties between the methods, and logistic regression to test the association between frailty and mortality.

RESULTS

One hundred fifty-three patients were evaluated; average age was 65 (56-70) years, 50.9% were women, and the all-cause mortality rate was 2.6%. Forty-six patients were classified as living with frailty according to the physical frailty phenotype while 36 patients were rated frail by the FRAIL scale. In adults < 60 years of age, the FRAIL scale showed good accuracy (84.9%) and specificity (93.2%) but had low sensitivity (41.3%) and moderate agreement (Kappa = 0.41; p < 0.001) compared to the definition of the physical frailty phenotype. The adjusted logistic regression model showed that the patients with frailty assessed by the FRAIL scale had a greater chance of mortality than the non-frail patients (OR: 6.8; CI95%:1.477-31.513; p = 0.014).

CONCLUSION

Physical frailty phenotype identifies more patients as having pre-frailty and frailty in non-dialysis dependent patients as compared to the FRAIL scale. However, the FRAIL scale is a simple bedside tool that can be useful for screening for frailty and whose results were associated with mortality.

Narrative Review: Clinical Implications and Assessment of Frailty in Patients With Advanced CKD

Frailty is a multidimensional clinical syndrome characterized by low physical activity, reduced strength, accumulation of multiorgan deficits, decreased physiological reserve, and vulnerability to stressors. Frailty has key social, psychological, and cognitive implications. Frailty is accelerated by uremia, leading to a high prevalence of frailty in patients with advanced chronic kidney disease (CKD) and end-stage kidney disease (ESKD) as well as contributing to adverse outcomes in this patient population. Frailty assessment is not routine in patients with CKD; however, a number of validated clinical assessment tools can assist in prognostication. Frailty assessment in nephrology populations supports shared decision-making and advanced communication and should inform key medical transitions. Frailty screening and interventions in CKD or ESKD are a developing research priority with a rapidly expanding literature base.

Pharmacologic therapeutics in sarcopenia with chronic kidney disease

Inflammation, metabolic acidosis, renin-angiotensin system activation, insulin resistance, and impaired perfusion to skeletal muscles, among others, are possible causes of uremic sarcopenia. These conditions induce the activation of the nuclear factor-kappa B and mitogen-activated protein kinase pathways, adenosine triphosphate ubiquitin-proteasome system, and reactive oxygen species system, resulting in protein catabolism. Strategies for the prevention and treatment of sarcopenia in chronic kidney disease (CKD) are aerobic and resistance exercises along with nutritional interventions. Anabolic hormones have shown beneficial effects. Megestrol acetate increased weight, protein catabolic rate, and albumin concentration, and it increased intracellular water component and muscle mass. Vitamin D supplementation showed improvement in physical function, muscle strength, and muscle mass. Correction of metabolic acidosis showed an increase in protein intake, serum albumin levels, body weight, and mid-arm circumference. The kidney- gut-muscle axis indicates that dysbiosis and changes in gut-derived uremic toxins and short-chain fatty acids affect muscle mass, composition, strength, and functional capacity. Biotic supplements, AST-120 administration, hemodiafiltration, and preservation of residual renal function are alleged to reduce uremic toxins, including indoxyl sulfate (IS) and p-cresyl sulfate (PCS). Synbiotics reversed the microbiota change in CKD patients and decreased uremic toxins. AST-120 administration changed the overall gut microbiota composition in CKD. AST-120 prevented IS and PCS tissue accumulation, ameliorated muscle atrophy, improved exercise capacity and mitochondrial biogenesis, restored epithelial tight junction proteins, and reduced plasma endotoxin levels and markers of oxidative stress and inflammation. In a human study, the addition of AST-120 to standard treatment had modest beneficial effects on gait speed change and quality of life.

Sarcopenia versus clinical frailty scale in predicting the risk of postoperative mortality after emergency laparotomy: a retrospective cohort study

OBJECTIVES

To compare predictive significance of sarcopenia and clinical frailty scale (CFS) in terms of postoperative mortality in patients undergoing emergency laparotomy METHODS: In compliance with STROCSS statement standards, a retrospective cohort study with prospective data collection approach was conducted. The study period was between January 2017 and January 2022. All adult patients with non-traumatic acute abdominal pathology who underwent emergency laparotomy in our centre were included. The primary outcome was 30-day mortality and secondary outcomes were in-hospital mortality and 90-day mortality. The predictive value of sarcopenia and CFS were compared using the receiver operating characteristic (ROC) curve analysis and multivariable binary logistic regression analysis.

RESULTS

A total of 1043 eligible patients were included. The risk of 30-day mortality, in-hospital mortality, and 90-day mortality were 8%, 10%, and 11%, respectively. ROC curve analysis suggested that sarcopenia is a significantly stronger predictor of 30-day mortality (AUC: 0.87 vs. 0.70, P<0.0001), in-hospital mortality (AUC: 0.79 vs. 0.67, P=0.0011), and 90-day mortality (AUC: 0.79 vs. 0.67, P=0.0009) compared with CFS. Moreover, multivariable binary logistic regression analysis identified sarcopenia as an independent predictor of mortality [coefficient: 4.333, OR: 76.16 (95% CI 37.06-156.52), P<0.0001] but not the CFS [coefficient: 0.096, OR: 1.10 (95% CI 0.88-1.38), P=0.4047].

CONCLUSIONS

Sarcopenia is a stronger predictor of postoperative mortality compared with CFS in patients undergoing emergency laparotomy. It cancels out the predictive value of clinical frailty scale in multivariable analyses; hence among the two variables, sarcopenia deserves to be included in preoperative predictive tools.

Clinical implications of frailty in peritoneal dialysis patients - A prospective observational study

BACKGROUND

Frailty is an age-related condition that predicts adverse outcomes. The study was aimed to investigate the clinical implications of frailty evolution in patients undergoing peritoneal dialysis (PD).

METHOD

In this prospective study, all new-onset (<6 months) and prevalent (≧6 months) PD patients completed frailty assessment at entry and 6 months by a semiautomated frailty index of 80 risk factors (FI80) which also contained the 5 components of Fried frailty phenotype. A score ≧13/80 (FI80 > 0.16) or ≧3/5 (frailty phenotype) was designated to define frailty.

RESULT

337 PD patients were recruited (new-onset 23.4%, prevalent 76.6%). Two hundred (59.3%) and 163 (48.4%) patients were frail by FI80 and frailty phenotype, respectively. Predictors for frailty were old age, dialysis, diabetes mellitus, gout and sleep disorder. New-onset patients aged <55 years displayed the best evolution of frailty over 6 months (stable or improved, n = 29/47, 61.7% by FI80, p = 0.0293), compared with other groups. Survival analysis found that frail patients exhibited the worse outcomes (overall death and hospitalization). Poisson regression showed frailty was associated with increased utilizations of outpatient and ER services; however multivariate Cox models identified only diabetes, gout and low body mass index (<19 kg/m2), but not frailty, predicted overall death and hospitalizations.

CONCLUSION

Frailty is a common medical condition in PD patients, and the status of which can be stabilized or improved in new-onset, young patients at least over the short term. Compared with frailty, certain comorbidities (diabetes and gout) and undernutrition appeared to be more robust in the prediction of adverse outcomes.

Relationship between Handgrip Strength and Incident Diabetes in Korean Adults According to Gender: A Population-Based Prospective Cohort Study

(1) Background: Diabetes mellitus (DM) is a well-known disease that causes comorbidities such as chronic kidney disease (CKD) and cardiovascular disease. Therefore, it is necessary to develop diagnostic tools to prevent DM. Handgrip strength, a known diagnostic tool for sarcopenia, is a predictor of several diseases. However, the value of handgrip strength as an indicator of incident DM in Asian populations remains unknown. This study aimed to identify the relationship between handgrip strength and incidence of DM in Korean adults according to sex. (2) Methods: A total of 173,195 participants registered in a nationwide cohort were included in this study. After applying the exclusion criteria, 33,326 participants remained. DM occurred in 1473 individuals during the follow-up period (mean follow-up period, 4.1 years). To reduce the impact of body size, the study population was subdivided into quartiles of relative handgrip strength, defined as absolute handgrip strength divided by body mass index. Multivariate Cox regression analysis revealed that the relative handgrip strength was inversely associated with new-onset DM. (3) Results: Compared with the lowest quartile (Q1), the hazard ratios (HRs) [95% confidence intervals (CIs)] for new-onset DM for the highest quartiles (Q4) was 0.60 (0.43-0.84) in men and 0.72 (0.52-0.99) in women after adjusting for confounding factors. The incidence of DM decreased with the increase in the relative handgrip strength. These inverse relationships were statistically more significant in men than in women. (4) Conclusions: This novel study revealed that relative handgrip strength is related to incident DM in both men and women. Relative handgrip strength can be used as a practical tool to prevent DM. Regular measurement of handgrip strength can be used to detect DM.

Handgrip strength and all-cause mortality in patients with chronic kidney disease: an updated systematic review and meta-analysis of cohort studies

OBJECTIVES

In observational studies, handgrip strength (HGS), a prognostic marker for healthy aging, has been associated with several chronic disease outcomes. The present systematic review and meta-analysis aimed to determine the quantitative relationship between HGS and the risk of all-cause mortality in patients with chronic kidney disease (CKD).

METHODS

Search PubMed, Embase, and Web of Science databases. The search was performed from inception to July 20, 2022, and the search was updated in February 2023. Cohort studies were included exploring the relationship between handgrip strength and the risk of all-cause mortality in patients with chronic kidney disease. Effect estimates and 95% confidence intervals (95% CI) were extracted from the studies to perform pooling. The quality of included studies was assessed using the Newcastle-Ottawa scale. We evaluated the overall certainty of evidence using Grades of Recommendation, Assessment, Development, and Evaluation (GRADE).

RESULTS

This systematic review included 28 articles. A random-effects meta-analysis that included 16,106 patients with CKD showed that participants with lower HGS had an increased mortality risk of 96.1% compared to higher HGS (HR: 1.961; 95% CI 1.591-2.415) (GRADE: very low). Moreover, this association was independent of baseline mean age and follow-up time. In 2,967 patients with CKD, a random-effects model-based meta-analysis showed that for each 1-unit increase in HGS, the risk of death in patients with CKD was reduced by 3.9% (HR: 0.961; 95% CI 0.949-0.974) (GRADE: moderate).

CONCLUSIONS

In patients with CKD, better HGS is associated with a lower risk of all-cause mortality. This study supports using HGS as a strong predictor of mortality in this population.

Prediction of the sarcopenia in peritoneal dialysis using simple clinical information: A machine learning-based model

INTRODUCTION

Sarcopenia is associated with significant cardiovascular risk, and death in patients undergoing peritoneal dialysis (PD). Three tools are used for diagnosing sarcopenia. The evaluation of muscle mass requires dual energy X-ray absorptiometry (DXA) or computed tomography (CT), which is labor-intensive and relatively expensive. This study aimed to use simple clinical information to develop a machine learning (ML)-based prediction model of PD sarcopenia.

METHODS

According to the newly revised Asian Working Group for Sarcopenia (AWGS2019), patients were subjected to complete sarcopenia screening, including appendicular skeletal muscle mass, grip strength, and five-time chair stand time test. Simple clinical information such as general information, dialysis-related indices, irisin and other laboratory indices, and bioelectrical impedance analysis (BIA) data were collected. All data were randomly split into training (70%) and testing (30%) sets. Difference, correlation, univariate, and multivariate analyses were used to identify core features significantly associated with PD sarcopenia.

RESULT

12 core features (C), namely, grip strength, body mass index (BMI), total body water value, irisin, extracellular water/total body water, fat-free mass index, phase angle, albumin/globulin, blood phosphorus, total cholesterol, triglyceride, and prealbumin were excavated for model construction. Two ML models, the neural network (NN), and support vector machine (SVM) were selected with tenfold cross-validation to determine the optimal parameter. The C-SVM model showed a higher area under the curve (AUC) of 0.82 (95% confidence interval [CI]: 0.67-1.00), with a highest specificity of 0.96, sensitivity of 0.91, positive predictive value (PPV) of 0.96, and negative predictive value (NPV) of 0.91.

CONCLUSION

The ML model effectively predicted PD sarcopenia and has clinical potential to be used as a convenient sarcopenia screening tool.

Use of frailty assessment instruments in nephrology populations: a scoping review

BACKGROUND

Frailty is a clinical syndrome of accelerated aging associated with adverse outcomes. Frailty is prevalent among patients with chronic kidney disease but is infrequently assessed in clinical settings, due to lack of consensus regarding frailty definitions and diagnostic tools. This study aimed to review the practice of frailty assessment in nephrology populations and evaluate the context and timing of frailty assessment.

METHODS

The search included published reports of frailty assessment in patients with chronic kidney disease, undergoing dialysis or in receipt of a kidney transplant, published between January 2000 and November 2021. Medline, CINAHL, Embase, PsychINFO, PubMed and Cochrane Library databases were examined. A total of 164 articles were included for review.

RESULTS

We found that studies were most frequently set within developed nations. Overall, 161 studies were frailty assessments conducted as part of an observational study design, and 3 within an interventional study. Studies favoured assessment of participants with chronic kidney disease (CKD) and transplant candidates. A total of 40 different frailty metrics were used. The most frequently utilised tool was the Fried frailty phenotype. Frailty prevalence varied across populations and research settings from 2.8% among participants with CKD to 82% among patients undergoing haemodialysis. Studies of frailty in conservatively managed populations were infrequent (N = 4). We verified that frailty predicts higher rates of adverse patient outcomes. There is sufficient literature to justify future meta-analyses.

CONCLUSIONS

There is increasing recognition of frailty in nephrology populations and the value of assessment in informing prognostication and decision-making during transitions in care. The Fried frailty phenotype is the most frequently utilised assessment, reflecting the feasibility of incorporating objective measures of frailty and vulnerability into nephrology clinical assessment. Further research examining frailty in low and middle income countries as well as first nations people is required. Future work should focus on interventional strategies exploring frailty rehabilitation.

STING signaling in inflammaging: a new target against musculoskeletal diseases

Stimulator of Interferon Gene (STING) is a critical signaling linker protein that plays a crucial role in the intrinsic immune response, particularly in the cytoplasmic DNA-mediated immune response in both pathogens and hosts. It is also involved in various signaling processes in vivo. The musculoskeletal system provides humans with morphology, support, stability, and movement. However, its aging can result in various diseases and negatively impact people's lives. While many studies have reported that cellular aging is a leading cause of musculoskeletal disorders, it also offers insight into potential treatments. Under pathological conditions, senescent osteoblasts, chondrocytes, myeloid cells, and muscle fibers exhibit persistent senescence-associated secretory phenotype (SASP), metabolic disturbances, and cell cycle arrest, which are closely linked to abnormal STING activation. The accumulation of cytoplasmic DNA due to chromatin escape from the nucleus following DNA damage or telomere shortening activates the cGAS-STING signaling pathway. Moreover, STING activation is also linked to mitochondrial dysfunction, epigenetic modifications, and impaired cytoplasmic DNA degradation. STING activation upregulates SASP and autophagy directly and indirectly promotes cell cycle arrest. Thus, STING may be involved in the onset and development of various age-related musculoskeletal disorders and represents a potential therapeutic target. In recent years, many STING modulators have been developed and used in the study of musculoskeletal disorders. Therefore, this paper summarizes the effects of STING signaling on the musculoskeletal system at the molecular level and current understanding of the mechanisms of endogenous active ligand production and accumulation. We also discuss the relationship between some age-related musculoskeletal disorders and STING, as well as the current status of STING modulator development.

Respiratory muscle training with electronic devices in the postoperative period of hepatectomy: A randomized study

BACKGROUND

Many studies have been developed with a focus on surgical techniques and drugs, but few that address the importance of rehabilitation in the pre and postoperative period, and the specific benefits for each surgical procedure or type of neoplasm, aiming to minimize respiratory complications in the postoperative period.

AIM

To compare the strength of the respiratory muscles in the pre and postoperative periods of hepatectomy by laparotomy and to verify the incidence of postoperative pulmonary complications among the groups studied.

METHODS

Prospective, randomized, clinical trial study that compared the inspiratory muscle training group (GTMI) with the control group (CG). After the collection of sociodemographic and clinical data, in both groups, preoperatively, on the first and fifth postoperative days, vital signs and pulmonary mechanics were evaluated and recorded. Albumin and bilirubin values were recorded for the albumin-bilirubin (ALBI) score. After randomization and allocation of participants, those in the CG underwent conventional physical therapy and those in the GTMI underwent conventional physical therapy plus inspiratory muscle, in both groups for five postoperative days.

RESULTS

Of 76 subjects met eligibility criteria. The collection of 41 participants was completed: 20 in the CG and 21 in the GTMI. The most frequent diagnosis was 41.5% with liver metastasis, followed by 26.8% with hepatocellular carcinoma. As for respiratory complications in the GTMI, there was no incidence. In the CG, there were three respiratory complications. Patients in the CG classified as ALBI score 3 presented, statistically, a higher energy value compared to patients classified as ALBI score 1 and 2 (P = 0.0187). Respiratory variables, measured preoperatively and on the first postoperative day, had a significant drop in both groups from the preoperative to the first postoperative day (P ≤ 0.0001). When comparing the preoperative period and the fifth postoperative day between the GTMI and the CG, the maximal inspiratory pressure variable in the GTMI was statistically significant (P = 0.0131).

CONCLUSION

All respiratory measures showed a reduction in the postoperative period. Respiratory muscle training using the Powerbreathe^® device increased maximal inspiratory pressure and this may have contributed to a shorter hospital stay and better clinical outcome.

Comparison of Frailty Criteria, Cognitive Function, Depressive and Insomnia Symptoms in Men with Localized and Advanced Prostate Cancer under Androgen Deprivation Therapy

BACKGROUND

Prostate cancer (PCa) is considered one of the most important medical problems in the male population, with a very high incidence after the age of 65. Frailty represents one of the most critical issues facing healthcare due to its inherent relationship with poor healthcare outcomes. The physical phenotype of frailty syndrome based on Fried criteria has been associated with poor outcomes, morbidity, and premature mortality. To date, there are few studies that have analyzed frailty syndrome in patients with localized and advanced (mPCa) disease under androgen-deprivation therapy.

OBJECTIVE

Our goal was to assess whether there are differences in frailty criteria between mPCa and localized PCa. We also evaluated the role of other geriatric variables such as depressive and insomnia symptoms, which are frequently reported in cancer patients.

METHODS

In this cross-sectional study, frailty syndrome was evaluated in both groups, as well as its possible relationship with cognitive functions, depressive and insomnia symptoms, and other clinical variables related to PCa and its treatment. Frailty was defined on Fried's criteria: low lean mass, weakness, self-reported exhaustion, low activity level, and slow walking speed; prefrailty was defined as having one or two of those criteria and frailty as having three or more, depressive symptoms were defined by the Yesavage scale, cognitive functions with the Mini-Mental examination test, and insomnia symptoms by the Athens scale and self-reported health status.

RESULTS

The prevalence of prefrailty/frailty was slightly higher in mPCa compared to localized PCa (81.5% versus 72.3%, respectively), however by analyzing each of the frailty criteria, two of them were significantly reduced in mPCa compared to localized PCa patients, e.g., gait speed (p = 0.001) and muscle strength (p = 0.04). The reduced gait speed and muscle strength in mPCa were not due to the increased age in mPCa group, or to an increase in comorbidities or shorter time under androgen-deprivation therapy. The symptoms of insomnia were significantly higher in mPCa patients compared to those with localized PCa (p < 0.05) whereas cognitive functions or depressive symptoms were not significantly different between the two groups.

CONCLUSION

Patients with mPCa under androgen-deprivation therapy display higher alterations in gait speed and muscular strength and insomnia symptoms, thus interventions should be aimed to reduce these alterations in order to limit adverse outcomes related to them and to improve quality of life in these patients.

From MIA to FIFA: The vicious matrix of frailty, inflammation, fluid overload and atherosclerosis in peritoneal dialysis

Cardiovascular disease (CVD) is a major cause of mortality and morbidity in peritoneal dialysis (PD) patients. Two decades ago, the common co-existence of malnutrition and systemic inflammation PD patients with atherosclerosis and CVD led to the proposed terminology of 'malnutrition-inflammation-atherosclerosis (MIA) syndrome'. Although the importance of malnutrition is well accepted, frailty represents a more comprehensive assessment of the physical and functional capability of the patient and encompasses the contributions of sarcopenia (a key component of malnutrition), obesity, cardiopulmonary as well as neuropsychiatric impairment. In recent years, it is also increasingly recognized that fluid overload is not only the consequence but also play an important role in the pathogenesis of CVD. Moreover, fluid overload is closely linked with the systemic inflammatory status, presumably by gut oedema, gastrointestinal epithelial barrier dysfunction and leakage of bacterial fragments to the systemic circulation. There are now a wealth of published evidence to show intricate relations between frailty, inflammation, fluid overload and atherosclerotic disease in patients with chronic kidney disease (CKD) and those on PD, a phenomenon that we propose the term 'FIFA complex'. In this system, frailty and atherosclerotic disease may be regarded as two patient-oriented outcomes, while inflammation and fluid overload are two inter-connected pathogenic processes. However, there remain limited data on how the treatment of one component affect the others. It is also important to define how treatment of fluid overload affect the systemic inflammatory status and to develop effective anti-inflammatory strategies that could alleviate atherosclerotic disease and frailty.

Higher Muscle Mass and Higher Serum Prealbumin Levels Are Associated with Better Survival in Hemodialysis Patients during a Five-Year Observation Period

BACKGROUND

Dialysis is the most commonly used renal replacement therapy in patients with end-stage renal disease. The mortality rate of hemodialysis patients is 15-20%, with cardiovascular complications being the most common. There is an association between the severity of atherosclerosis and both the development of protein-calorie malnutrition and inflammatory mediators. The aim of this study was to assess the relationship between biochemical markers of nutritional status, body composition and survival in hemodialysis patients.

METHODS

Fifty-three hemodialysis patients were included in the study. Serum albumin, prealbumin, and IL-6 levels were measured, as well as body weight, body mass index, fat content and muscle mass. The five-year survival of patients was calculated using Kaplan-Meier estimators. The long-rank test was used for univariate comparison of survival curves, and the Cox proportional hazards model was used for multivariate analysis of survival predictors.

RESULTS

There were 47 deaths, 34 of which were due to cardiovascular disease. The hazard ratio (HR) for age in the middle-aged group (55-65 years) was 1.28 (confidence interval [CI] 0.58, 2.79) and 5.43 (CI 2.1, 14.07; statistically significant) for the oldest age group (over 65 years). A prealbumin level above 30 mg/dl was associated with an HR of 0.45 (CI 0.24, 0.84). Serum prealbumin (odds ratio [OR] = 5.23; CI 1.41, 19.43; p = 0.013) and muscle mass (OR = 7.5; CI 1.31, 43.03; p = 0.024) were significant predictors of all-cause mortality.

CONCLUSIONS

Prealbumin level and muscle mass were associated with increased mortality risk. Identification of these factors may improve the survival of hemodialysis patients.

Sarcopenic Obesity Versus Nonobese Sarcopenia in Hemodialysis Patients: Differences in Nutritional Status, Quality of Life, and Clinical Outcomes

OBJECTIVE

Sarcopenia and sarcopenic obesity (SO) are linked to unfavorable prognosis in maintenance hemodialysis (MHD) populations. We tested whether nonobese sarcopenia and SO, as different stages of extreme protein-energy wasting, have different prognoses.

METHODS

In this prospective observational study, 261 MHD patients were recruited from October 2010 to April 2012 and followed until October 2020. Two definitions were used to diagnose sarcopenia: the European Working Group on Sarcopenia in Older People consensus and the Foundation for the National Institutes of Health (FNIH) Biomarkers Consortium criteria. Obesity was determined as the percentage of total body fat, ≥27% for men and ≥38% for women. Data for all-cause and cardiovascular morbidity and mortality, baseline nutrition markers, inflammation and oxidative stress, adipokines, body composition parameters, handgrip strength, and quality of life (QoL) scores were measured.

RESULTS

According to European Working Group on Sarcopenia in Older People, 115 (44.1%) patients were sarcopenic and 120 (46.0%) according to FNIH definitions. Of them, 28.4% and 34.5% were SO, respectively. Higher levels of albumin, creatinine, uric acid, leptin, phase angle, better nutritional scores, and lower adiponectin levels characterized SO patients compared with nonobese sarcopenic patients regardless of indexing method. Better QoL scores were noted in SO compared with nonobese sarcopenic patients using the FNIH sarcopenia criteria. The hazard of all-cause death, cardiovascular death, and first cardiovascular event for patients with SO was lower compared with the nonobese patients after multivariate adjustments. Statistical significance of these associations disappeared after including fat mass in multivariate models.

CONCLUSIONS

MHD patients with SO have better nutritional status and prognosis for cardiovascular events, all-cause and cardiovascular disease mortality, and possibly better QoL compared with nonobese sarcopenic MHD patients. The better prognosis appears to be entirely due to the excess fat, which is protective in sarcopenic MHD patients similar to that described in the entire MHD population.

Established risk prediction models for the incidence of a low lean tissue index in patients with peritoneal dialysis

Objective

The objective of this study is to investigate the incidence of low lean tissue index (LTI) and the risk factors for low LTI in peritoneal dialysis (PD) patients, including to establish risk prediction models.

Methods

A total of 104 PD patients were enrolled from October 2019 to 2021. LTI was measured by bioimpedance spectroscopy. Multivariate logistic regression and machine learning were used to analyze the risk factors for low LTI in PD patients. Kaplan–Meier analysis was used to analyze the survival rate of patients with low LTI.

Results

The interleukin-6 (IL-6) level, red cell distribution width (RDW), overhydration, body mass index (BMI), and the subjective global assessment (SGA) rating significantly differed between the low LTI and normal LTI groups (all p < 0.05). Multivariate logistic regression showed that IL-6 (1.10 [95% CI: 1.02–1.18]), RDW (1.87 [95% CI: 1.18–2.97]), BMI (0.97 [95% CI: 0.68–0.91]), and the SGA rating (6.33 [95% CI: 1.59–25.30]) were independent risk factors for LTI. Cox regression analysis showed that low LTI (HR 3.14, [95% CI: 1.12–8.80]) was the only significant risk factor for all-cause death in peritoneal dialysis patients. The decision process to predict the incidence of low LTI in PD patients was established by machine learning, and the area under the curve of internal validation was 0.6349.

Conclusions

Low LTI is closely related to mortality in PD patients. Microinflammatory status, high RDW, low BMI and low SGA rating are risk factors for low LTI in PD patients. The developed prediction model may serve as a useful tool for assessing low LTI in PD patients.

Association of sarcopenia and its components with clinical outcomes in patients undergoing peritoneal dialysis

Background: Further studies are needed to identify whether muscle mass, muscle strength, or sarcopenia is the best indicator of survival in patients undergoing peritoneal dialysis (PD). We aimed to compare the association of sarcopenia and its components with survival in patients undergoing PD.Methods: We identified all patients with prevalent PD (n = 199). We routinely recommended handgrip strength (HGS) and lean mass measurements using dual energy X-ray absorptiometry in all patients with PD. Sarcopenia was defined using cutoff values from the Asian Working Group for Sarcopenia. We evaluated the patient and technique survival rates.Results: The number of patients with low HGS was 95 (47.7%). The median follow-up interval was 17 months (interquartile range, 13–21 months). Kaplan-Meier curve analysis showed that patients with low HGS or sarcopenia had poorer patient and technique survival compared with patients with normal HGS or without sarcopenia. Cox regression analysis showed that patients with low HGS had greater hazard ratios for patient death and technique failure compared with those with normal HGS. However, patients with low muscle mass did not show significant hazard ratios for patient death or technique failure compared with those with normal muscle mass. Patients with sarcopenia had significantly greater hazard ratios for patient death or technique failure than those without sarcopenia only in univariate analysis.Conclusion: The present study demonstrated that HGS may be superior to muscle mass or sarcopenia for predicting patient or technique survival in patients undergoing PD.

What Exactly Makes Age a Risk Factor for an Unfavorable Outcome after Mitral Valve Surgery?

Objective: Age has an undeniable impact on perioperative mortality. However, it is not necessarily a predictor of frailty per se, as older patients have different outcomes. To verify specific conditions underlying frailty, we examined demographics, comorbidities, frequency, and distribution of postoperative complications influencing outcomes in a challenging cohort of patients undergoing mitral valve surgery. Methods: The study enrolled 1627 patients who underwent mitral valve surgery. Patients younger than 40 years who had been diagnosed with endocarditis were excluded. Patients were divided into three groups with ages ranging from 40−59 (n = 319), 60−74 (n = 795), and >75 years (n = 513). Baseline, comorbidities, postoperative complications, and mortality were recorded. Results: The older the patients were, the more frequently they suffered from pre- and postoperative renal insufficiency (p < 0.001). The likelihood of postoperative renal failure requiring dialysis was significantly higher with pre-existing renal failure. There was a significant association between postoperative renal insufficiency and the development of postoperative pleural or pericardial effusion (p < 0.001, p = 0.016). A significant decrease in BMI was observed in patients >75 years of age compared to the 60−74 years group (27.3 vs. 28.2 kg/m2, p = 0.007). The development of critical illnesses such as myopathy and neuropathy (CIP/CIM) was age-dependent and increased significantly with age (p = 0.04). Hospitalization duration and mortality also increased significantly with age (p = 0.013, p < 0.001). Conclusions: It appears that elderly patients with advanced renal failure have a significantly higher risk of mortality, postoperative renal failure, need for dialysis, and possibly the development of pleural and pericardial effusions in mitral valve surgery. In addition, more frequent CIP/CIM with concomitant decrease in BMI in the most advanced age group indicate sarcopenia and thus an additional feature of frailty besides renal failure.

The combination of phase angle and age has a good diagnostic value for sarcopenia in continuous ambulatory peritoneal dialysis patients

Aims

There are limited studies on phase angle and sarcopenia in continuous ambulatory peritoneal dialysis patients. So, we want to explore the association between phase angle and sarcopenia and find a more sensitive indicator for diagnosing sarcopenia.

Methods

We included 101 continuous ambulatory peritoneal dialysis patients from March 2022 to August 2022 and measured the phase angle and body composition by bioelectrical impedance analysis. All patients had their handgrip strength measured. Then, we divided patients into the sarcopenia (n = 30) group and non-sarcopenia (n = 71) group according to the sarcopenia diagnostic strategy formulated by the Asian Working Group for Sarcopenia. We used logistic regression to explore the risk factors of sarcopenia. We applied Receiver-operating characteristics curves to determine the diagnostic accuracy of these risk factors.

Results

After adjustments for sex, age, diabetes, BMI, extracellular water ratio, extra water, serum creatinine, total kt/v, and residual kt/v, phase angle correlated to handgrip strength and lowered limb muscle mass but not to skeletal muscle mass, upper arm muscle circumference, upper limb muscle mass and appendicular skeletal muscle mass index. In the multivariate logistic model, low phase angle and older age are risk factors for sarcopenia. The AUROC of phase angle for sarcopenia is 0.79 (95%CI, 0.70–0.86, P &lt; 0.01) for both sexes, 0.70 and 0.85 for females and males. After we combined age and phase angle as diagnostic indicators of sarcopenia, the AUROC is 0.91 (95%CI, 0.83–0.96, P &lt; 0.0001) in both sexes, 0.89 and 0.93 for females and males.

Conclusion

This study illustrates that age 52 or older is an independent risk factor for sarcopenia in continuous ambulatory peritoneal dialysis patients. Phase angle can act as a predictor of sarcopenia in those patients. But the combination of age and phase angle is more valuable in diagnosing sarcopenia.

Calf Circumference, a Valuable Tool to Predict Sarcopenia in Older People Hospitalized with Hip Fracture

Sarcopenia is an important risk factor for hip fracture in older people. Nevertheless, this condition is overlooked in clinical practice. This study aimed to explore the factors associated with sarcopenia among older patients hospitalized for hip fracture, to identify a predictive model of sarcopenia based on variables related to this condition, and to evaluate the performance of screening tools in order to choose the most suitable to be adopted in routine care of older people with hip fracture. A cross-sectional study was undertaken with 90 patients (mean age 83.4 ± 7.2 years), by assessing sociodemographic and clinical characteristics, anthropometric measures, such as body mass index (BMI) and calf circumference (CC), the functional status (Barthel Index), the nutritional status (MNA-SF), and the adherence to the Mediterranean Diet (MEDAS). Diagnosis of sarcopenia was established according to the criteria of the European Working Group on Sarcopenia in Older People (EWGSOP2). The analysis of variables associated with sarcopenia was performed using multivariate logistic regression models. Clusters of sarcopenia were explored with heatmaps and predictive risk models were estimated. Sarcopenia was confirmed in 30% of hip fracture patients. Variables with the strongest association with sarcopenia were BMI (OR = 0.79 [0.68−0.91], p < 0.05) and CC (OR = 0.64 [0.51−0.81], p < 0.01). CC showed a relatively high predictive capacity of sarcopenia (area under the curve: AUC = 0.82). Furthermore, CC could be a valuable tool to predict sarcopenia risk compared with the currently used screening tools, SARC-F and SARC-CalF (AUC, 0.819 vs. 0.734 and 0.576, respectively). More studies are needed to validate these findings in external study populations.

Prevalence of Sarcopenia and Its Impact on Cardiovascular Events and Mortality among Dialysis Patients: A Systematic Review and Meta-Analysis

Sarcopenia in end-stage kidney disease patients requiring dialysis is a frequent complication but remains an under-recognized problem. This meta-analysis was conducted to determine the prevalence of sarcopenia and explored its impacts on clinical outcomes, especially cardiovascular events, and mortality in dialysis patients. The eligible studies were searched from PubMed, Scopus, and Cochrane Central Register of Controlled trials up to 31 March 2022. We included studies that reported the interested outcomes, and the random-effects model was used for analysis. Forty-one studies with 7576 patients were included. The pooled prevalence of sarcopenia in dialysis patients was 25.6% (95% CI 22.1 to 29.4%). Sarcopenia was significantly associated with higher mortality risk (adjusted OR 1.83 (95% CI 1.40 to 2.39)) and cardiovascular events (adjusted OR 3.80 (95% CI 1.79 to 8.09)). Additionally, both low muscle mass and low muscle strength were independently related to increased mortality risk in dialysis patients (OR 1.71; 95% CI (1.20 to 2.44), OR 2.15 (95% CI 1.51 to 3.07)), respectively. This meta-analysis revealed that sarcopenia was highly prevalent among dialysis patients and shown to be an important predictor of cardiovascular events and mortality. Future intervention research to alleviate this disease burden in dialysis patients is needed.

1H NMR Urinary Metabolomic Analysis in Older Adults after Hip Fracture Surgery May Provide Valuable Information for Patient Profiling-A Preliminary Investigation

In these times of precision and personalized medicine, profiling patients to identify their needs is crucial to providing the best and most cost-effective treatment. In this study, we used urine metabolomics to explore the characterization of older adults with hip fractures and to explore the forecasting of patient outcomes. Overnight urine specimens were collected from 33 patients (mean age 80 ± 8 years) after hip fracture surgery during their stay at a rehabilitation hospital. The specimens were analyzed with ¹H NMR spectroscopy. We performed a metabolomics study regarding assessments of frailty status, Functional Independence Measure (FIM), and Short Physical Performance Battery (SPPB). The main metabolic variations concerned 10 identified metabolites: paracetamol derivatives (4 peaks: 2.15 ppm; 2.16 ppm; 7.13 ppm and 7.15 ppm); hippuric acid; acetate; acetone; dimethylamine; glycine; alanine; lactate; valine; TMAO. At baseline, the urinary levels of these metabolites were significantly higher (i) in frail compared with non-frail patients, (ii) in persons with poorer FIM scores, and (iii) in persons with poorer compared SPPB scores. Our findings suggested that patients with increased levels of urine metabolites associated with metabolic, inflammatory, and renal disorders presented clear signs of frailty, impaired functional independence, and poor physical performance. Metabolomics could be a valuable tool to further characterize older adults, especially after major medical events.

Impact of phase angle and sarcopenia estimated by bioimpedance analysis on clinical prognosis in patients undergoing hemodialysis: A retrospective study

Bioimpedance analysis (BIA) has been widely used in the evaluation of body composition in patients undergoing maintenance hemodialysis. We conducted this study to evaluate impact of phase angle (PA) and sarcopenia measured by BIA on clinical prognosis in these patients.This longitudinal retrospective study enrolled patients who underwent hemodialysis between January 2016 and March 2019. The patients were stratified into higher (> 4°) and lower (≤ 4.0°) PA groups. Sarcopenia was defined when the appendicular skeletal muscle mass was < 20 kg in men and < 15 kg in women.Of the 191 patients, 63.4% were men. The mean age was 64.2 ± 12.4 years. The lower PA group was older, had a higher proportion of women, a lower body mass index, lower albumin, cholesterol, uric acid, and phosphorus levels, and a higher incidence of history of coronary artery disease than the higher PA group. Linear regression analysis revealed that PA was significantly associated with body mass index (B = 0.18, P = .005), serum albumin (B = 0.23, P = .001), and creatinine levels (B = 0.32, P < .001). During a median follow-up of 16.7 months, 14.1% (n = 27) of patients experienced major adverse cardiovascular events and 11.0% (n = 21) died. Kaplan-Meier survival analysis showed that the higher PA group had significantly better survival, regardless of sarcopenia. Multivariate Cox analyses revealed that lower PA (0.51 [0.31-0.85], P = .010), higher IDWG (1.06 [1.01-1.12], P = .028) and C-reactive protein level (1.01 [1.01-1.02], P < .001), and a history of coronary artery disease (3.02 [1.04-8.77], P = .042) were significantly related to all-cause mortality after adjusting for other covariates.PA measured by BIA was an independent factor in the prediction of mortality in maintenance hemodialysis patients, regardless of sarcopenia. Intervention studies are needed to confirm if the improvement in PA is associated with better clinical outcome.

Comparison of Creatinine and Cystatin C to Estimate Renal Function in Geriatric and Frail Patients

The aim of this study was to compare estimated glomerular filtration rate (eGFR) with creatinine (eGFRcrea) and cystatin C (eGFRcys) in geriatric and frail patients. A retrospective, cross-sectional study was performed at a geriatric clinic in Stockholm (n = 95). The revised Lund−Malmö equation was used to calculate eGFRcrea and the Caucasian-Asian-Pediatric-Adult (CAPA) equation was used for eGFRcys. The absolute mean percentage difference between eGFRcrea and eGFRcys was used as a surrogate measure for accuracy in eGFR. Other outcome measures were consistency expressed in Lin’s concordance correlation coefficient and the proportion of consistent staging of renal failure. Subgroup analyses were performed with regard to frailty (according to Clinical Frailty Scale) and age. eGFRcys estimated lower GFR than eGFRcrea across the entire study population as well as in all subgroups (p < 0.05). Difference between the estimates increased with increasing frailty (r2 = 0.15, p < 0.01), but was not significantly affected by age (r2 = 0.004, p = 0.55). In conclusion, eGFRcys was significantly lower compared to eGFRcrea in geriatric and frail patients. Moreover, frailty had greater impact than age on the accuracy of eGFR. However, this study cannot determine if any of the estimates are preferable over the other in this patient group.

Sarcopenia and Mortality in Older Hemodialysis Patients

(1) Sarcopenia is a progressive loss of skeletal muscle mass and strength. The aim of this study was to determine the association of sarcopenia, defined according to the Working Group on Sarcopenia in Older People (EWGSOP2) diagnostic criteria, with mortality at 24 months in very elderly hemodialysis patients. (2) A prospective study was conducted in 60 patients on chronic hemodialysis who were older than 75 years. Sarcopenia was diagnosed according to EWGSOP2 criteria. Additionally, clinical, anthropometric and analytical variables and body composition by bioimpedance were assessed. The date and cause of death were recorded during 2 years of follow-up. (3) Among study participants, 41 (68%) were men, the mean age 81.85 ± 5.58 years and the dialysis vintage was 49.88 ± 40.29 months. The prevalence of probable sarcopenia was 75% to 97%, depending on the criteria employed: confirmed sarcopenia ranged from 37 to 40%, and severe sarcopenia ranged from 18 to 37%. A total of 30 (50%) patients died over 24 months. Sarcopenia probability variables were not related to mortality. In contrast, sarcopenia confirmation (appendicular skeletal muscle mass, ASM) and severity (gait speed, GS) variables were associated with mortality. In multivariate analysis, the hazard ratio (95% confidence interval) for all-cause death was 3.03 (1.14–8.08, p = 0.028) for patients fulfilling ASM sarcopenia criteria and 3.29 (1.04–10.39, p = 0.042) for patients fulfilling GS sarcopenia criteria. (4) The diagnosis of sarcopenia by EWGSOP2 criteria is associated with an increased risk of all-cause death in elderly dialysis patients. Specifically, ASM and GS criteria could be used as mortality risk markers in elderly hemodialysis patients. Future studies should address whether the early diagnosis and treatment of sarcopenia improve outcomes.

Health-Related Quality of Life Sleep Score Predicts Transfer to Hemodialysis among Patients on Peritoneal Dialysis

Despite the superiority of peritoneal dialysis (PD) over hemodialysis (HD) regarding health-related quality of life (HRQOL), the specific HRQOL domain(s) that predict unplanned HD transfer remains uncertain. In this cohort study, we assessed the HRQOL of 50 outpatients undergoing PD using the Japanese version 1.3 Kidney Disease Quality of Life-Short Form from March 2017 to March 2018 and prospectively analyzed the association of each HRQOL component with HD transfer until June 2021. During the follow-up (41.5 (13.0–50.1) months), 21 patients were transferred to HD. In a multivariate Cox proportional hazards model adjusted for age, sex, PD vintage, urine output, Charlson comorbidity index, and incremental shuttle walking test, a higher sleep score was significantly associated with lower HD transfer rates (HR 0.70 per 10, p = 0.01). An adjusted subdistribution hazard model where elected transition to HD, death, and transplantation were considered competing events of unintended HD transfer that showed sleep score as an exclusive predictor of HD transfer (HR 0.70 per 10, p = 0.002). Our results suggest that sleep score among the HRQOL subscales is instrumental in predicting HD transfer in patients undergoing PD.

Dietary Inflammatory Potential Is Associated With Sarcopenia Among Chronic Kidney Disease Population

Background

Sarcopenia, characterized by impaired muscle mass and function, is a common complication and the main reason for bad life quality and high mortality in chronic kidney disease (CKD). Limiting systemic inflammation is a potable intervention for sarcopenia. Dietary inflammatory potential can influence systemic inflammation. However, research about the association between dietary inflammatory potential and sarcopenia in CKD is limited.

Aim

To investigate the association between dietary inflammatory potential and sarcopenia in the CKD population.

Methods

We conducted a cross-section study based on the public database of the National Health and Nutrition Examination Survey (NHANES). In total, 2,569 adult CKD participants who had complete data for dietary inflammatory potential and sarcopenia were included. The dietary inflammatory potential was calculated by the dietary inflammation index (DII) score based on dietary recall interviews. We assessed sarcopenia via low skeletal muscle mass measured by dual-energy X-ray absorptiometry. Smooth curve fitting and a generalized linear mixed model were used to evaluate the relationship between DII and sarcopenia. Moreover, subgroup and sensitivity analyses were performed.

Results

The overall prevalence of sarcopenia among patients with CKD is 19.11%. Smooth curve fitting results displayed that the DII score is near-linear positively associated with sarcopenia. Logistic regression confirmed sarcopenia is independently related to DII scores (odds ratio [OR], 1.17; 95% CI, 1.06–1.29). Subgroup analyses revealed relatively stronger associations between DII and sarcopenia among patients with CKD with other sarcopenia risk factors, such as hypoalbuminemia, low energy intake, low protein intake, and comorbidities.

Conclusion

The dietary inflammatory potential is independently related to sarcopenia among patients with CKD. Anti-inflammatory diet patterns may be a protective intervention for CKD-associated sarcopenia.

Comparison of frailty, sarcopenia and protein energy wasting in a contemporary peritoneal dialysis cohort

BACKGROUND

More elderly frail patients are now treated by peritoneal dialysis (PD). Frailty, sarcopenia and protein energy wasting (PEW) are all associated with increased mortality. Simple screening tools are required to identify patients to allow for interventions. As such, we wished to review the prevalence of frailty and compare frailty with sarcopenia and PEW in a contemporary PD population.

PATIENTS AND METHODS

We used the Clinical Frailty Score (CFS) to determine frailty, bio-impedance body composition and hand grip strength (HGS) to determine sarcopenia and combining laboratory, body composition and protein nitrogen appearance rate (PNA) to assess PEW.

RESULTS

Records of 368 PD patients, 61% male, mean age 60.9 ± 16.1 years, body mass index (BMI) 26.2 ± 5.1 kg/m² were reviewed, with 71 classified as frail (19.3%; CFS > 4), and frailty associated with age (odds ratio (OR) 1.047, 95% confidence interval (CL) 1.01-1.085, p = 0.012), Stoke-Davies co-morbidity (OR 1.808, 95%CL 1.129-2.895, p = 0.014) and negatively with HGS (OR 0.906, 95% CL 0.897-0.992, p = 0.033); 17.7% met muscle loss and HGS criteria for sarcopenia, with fair agreement with frailty (kappa 0.24 (CL 0.09-0.38)). Only two patients (0.5%) met all four criteria for PEW, 26.1% met the reduced BMI criteria, 4.6% the serum albumin, 32.9% the PNA and 39.4% the reduced muscle mass. HGS correlated with lean muscle mass (r ² = 0.42, p < 0.001).

CONCLUSION

Using the CFS, 19.3% of patients were classified as frail, compared to 17.7% with sarcopenia and <1% with PEW. The CFS requires no special equipment or laboratory tests and was associated with age, co-morbidity and HGS weakness.

Diagnosis, prevalence, and mortality of sarcopenia in dialysis patients: a systematic review and meta-analysis

There is no consensus on the prevalence of sarcopenia or its impact on mortality in end-stage renal disease patients undergoing dialysis. This review aimed to summarize the diagnostic criteria of sarcopenia and its prevalence and impact on the mortality of end-stage renal disease patients undergoing dialysis. Embase, MEDLINE, PubMed, and Cochrane Library were searched from inception to 8 May 2021 to retrieve eligible studies that assessed muscle mass by commonly used instruments, such as dual-energy X-ray absorptiometry, bioelectrical impedance analysis, magnetic resonance imaging, and body composition monitor. Two assessment tools matched to study designs were employed to evaluate study quality. Pooled sarcopenia prevalence was calculated with 95% confidence interval (CI), and heterogeneity was estimated using the I2 test. Associations of sarcopenia with mortality were expressed as hazard ratio (HR) and 95% CI. The search identified 3272 studies, and 30 studies (6162 participants, mean age from 47.5 to 77.5 years) were analysed in this review. The risk of bias in the included studies was low to moderate. Twenty-two studies defined sarcopenia based on low muscle mass (LMM) plus low muscle strength and/or low physical performance, while eight studies used LMM alone. Muscle mass was assessed by different instruments, and a wide range of cut-off points were used to define LMM. Overall, sarcopenia prevalence was 28.5% (95% CI 22.9-34.1%) and varied from 25.9% (I2  = 94.9%, 95% CI 20.4-31.3%; combined criteria) to 34.6% (I2  = 98.1%, 95% CI 20.9-48.2%; LMM alone) (P = 0.247 between subgroups). The statistically significant differences were not found in the subgroups of diagnostic criteria (P > 0.05) and dialysis modality (P > 0.05). Additionally, the sarcopenia prevalence could not be affected by average age [regression coefficient 0.004 (95% CI: -0.005 to 0.012), P = 0.406] and dialysis duration [regression coefficient 0.002 (95% CI -0.002 to 0.005), P = 0.327] in the meta-regression. The pooled analyses showed that combined criteria of sarcopenia were related to a higher mortality risk [HR 1.82 (I2  = 26.3%, 95% CI 1.38-2.39)], as was LMM [HR 1.61 (I2  = 26.0%, 95% CI 1.31-1.99)] and low muscle strength [HR 2.04 (I2  = 80.4%, 95% CI 1.19-3.5)]. Although there are substantial differences in diagnostic criteria, sarcopenia is highly prevalent in dialysis patients and is linked to increased mortality. The standardization of sarcopenia diagnostic criteria would be beneficial, and future longitudinal studies are needed to investigate the prevalence and prognostic value of sarcopenia in dialysis patients.

Height-adjusted lean body mass and its associations with physical activity and kidney function in pediatric kidney transplantation

BACKGROUND

Although LBM is positively associated with health outcomes, studies assessing determinants for the accrual of ht-LBM, such as physical activity, are limited. This study aimed to assess ht-LBM levels in pediatric kidney transplant recipients and test its association with baseline and contemporaneous variables, including physical activity.

METHODS

A retrospective cross-sectional review was performed on 46 pediatric kidney transplant recipients, and a longitudinal review was performed on a subset of recipients with serial post-transplant (n = 21) and pre/post-transplant (n = 11) ht-LBM measurements. Ht-LBM measurements were obtained using DXA scans.

RESULTS

This cohort was 16.0 (IQR 12.3, 17.7) years old, 56.5% male and 46 ± 45 months post-transplant with a mean ht-LBM of 15.1 ± 2.5 kg/m² . A median ht-LBM increase of 1.6 kg/m² (IQR - 0.1, 2.6 kg/m² ; p < .01) was observed, over 29.2 ± 12.0 months from the earliest post-transplant scan obtained at 46 ± 25 months post-transplant until the most recent post-transplant scan. A 1.7 ± 1.4 kg/m² (p < .01) increase was observed between pre- and post-transplant DXA scans which were taken at 12 ± 11 months pre-transplant and 13 ± 6 months post-transplant, respectively. In separate adjusted models, lower physical activity questionnaire scores (n = 17, beta = 1.55, p = .02), faster rate of estimated glomerular filtration rate decline (beta = 0.05, p < .048) adjusted for annualized change in BSA, and younger age at scan (beta = 0.32, p < .01) were each significant predictors of lower ht-LBM.

CONCLUSIONS

Physical activity and kidney function may influence ht-LBM in the pediatric kidney transplant population.

Additive Effect of Sarcopenia and Anemia on the 10-Year Risk of Cardiovascular Disease in Patients with Type 2 Diabetes

OBJECTIVE

To investigate the association between sarcopenia and anemia and the 10-year cardiovascular disease risk in diabetic patients.

METHODS

A cross-sectional study was conducted involving 4673 hospitalized patients (2271 men and 2402 women) with type 2 diabetes mellitus, with an average age of 60.66 ± 11.93 years, of whom 542 were followed up for a median follow-up period of 24 months. All participants underwent body composition measurements, and they were grouped by sex and presence of sarcopenia using the Framingham risk model to assess their 10-year cardiovascular risk. According to the changes in the cardiovascular risk during follow-up, the patients were divided into four groups: low-low, low-high, high-low, and high-high.

RESULTS

The prevalence of anemia was higher in the sarcopenia group than in the nonsarcopenia group (11.5% vs. 24.1% for men, P < 0.001; 13.9% vs. 19.7% for women, P < 0.05), and the difference remained significant after adjusting for confounders. Patients with sarcopenia and without anemia had a 46.2% increased risk of high 10-year cardiovascular disease (CVD) (odds ratio (OR) = 1.462, 95% confidence interval (CI) 1.085-1.972, P = 0.013), and the risk was twofold higher in patients with sarcopenia and anemia than in those without (OR = 3.283, 95% CI 2.038-5.289, P < 0.001). In follow-up studies, sarcopenia was associated with an increased risk of CVD at 10 years, and a reduction in appendicular skeletal muscle mass index independently predicted the increased risk of CVD.

CONCLUSION

Sarcopenia is associated with an increased risk of anemia, and the presence of both has an additive effect on the 10-year CVD risk in patients with type 2 diabetes. Loss of muscle mass can independently predict an increased CVD risk in diabetic patients.

Sarcopenia in Chronic Kidney Disease: A Scoping Review of Prevalence, Risk Factors, Association with Outcomes, and Treatment

Sarcopenia, a condition characterized by loss of skeletal muscle mass and function, has important clinical ramifications. We aimed to map the existing literature about prevalence, risk factors, associated adverse outcomes, and treatment of sarcopenia in individuals with chronic kidney disease (CKD). A scoping review of the literature was conducted to identify relevant articles published from databases' inception to September 2019. Individuals with CKD, regardless of their disease stage and their comorbidities, were included. Only studies with sarcopenia diagnosed using both muscle mass and function, based on published consensus definitions, were included. For studies on treatment, only randomized controlled trials with at least one sarcopenia parameter as an outcome were included. Our search yielded 1318 articles, of which 60 from were eligible for this review. The prevalence of sarcopenia ranged from 4 to 42% according to the definition used, population studied, and the disease stage. Several risk factors for sarcopenia were identified including age, male gender, low BMI, malnutrition, and high inflammatory status. Sarcopenia was found to be associated with several adverse outcomes, including disabilities, hospitalizations, and mortality. In CKD subjects, several therapeutic interventions have been assessed in randomized controlled trial with a muscle mass, strength, or function endpoint, however, studies focusing on sarcopenic CKD individuals are lacking. The key interventions in the prevention and treatment of sarcopenia in CKD seem to be aerobic and resistance exercises along with nutritional interventions. Whether these interventions are effective to treat sarcopenia and prevent clinical consequences in this population remains to be fully determined.

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.

Associations between homocysteine, inflammatory cytokines and sarcopenia in Chinese older adults with type 2 diabetes

Background

Sarcopenia, an age-related disease, has been implicated as both a cause and consequence of type 2 diabetes mellitus (T2DM) and a symbol of poor prognosis in older adults with T2DM. Therefore, early detection and effective treatment of sarcopenia are particularly important in older adults with T2DM. We aimed to investigate the prevalence of sarcopenia in Chinese older T2DM patients and explore whether homocysteine and inflammatory indexes could serve as biomarkers and participate in the development process of sarcopenia.

Methods

T2DM patients aged over 60 years were consecutively recruited from the ward of department of Endocrinology, Xuanwu Hospital between April 2017 and April 2019. Sarcopenia was defined based on the standard of the Asian Working Group of Sarcopenia, including muscle mass, grip strength and gait speed. Logistic regression was used to explore the association between biochemical indicators and sarcopenia. Receiver operating characteristic (ROC) curves were applied to determine the diagnostic effect of these clinical indicators.

Results

Totally 582 older adults with T2DM were characterized and analyzed in the study. Approximately 8.9% of the older T2DM patients had sarcopenia. After adjusting for age, sex, body mass index (BMI) and hemoglobin A1c (HbA1c), increased concentrations of homocysteine [odds ratio (OR): 2.829; 95% confidence interval (CI), 1.064–7.525] and high-sensitive C-reactive protein (hs-CRP) (OR: 1.021; 95% CI, 1.001–1.042) were independent predictors of sarcopenia; but not interleukin-6. The combination of age, sex, BMI and HbA1c provided a discriminatory effect of sarcopenia with an area under the curve (AUC) of 0.856, when homocysteine was added to the model, the value of the ROC curve was further improved, with an AUC of 0.861.

Conclusion

In the current study, we demonstrated a positive correlation of homocysteine, hs-CRP with sarcopenia in older adults with T2DM and the relationship remained significant even after adjustment for HbA1c. These biomarkers (homocysteine and hs-CRP) may play important roles in the pathological process of sarcopenia.

Predictive Value of Objective Nutritional Indexes in Technique Failure in Peritoneal Dialysis Patients

OBJECTIVES

Patients undergoing peritoneal dialysis (PD) will encounter with a well-recognized challenge of technique failure (TF). We aimed to explore the predictive value of objective nutritional indexes in PD TF.

METHODS

This retrospective observational study included PD patients from August 2010 to March 2019. The Controlling Nutritional Status (CONUT) score, Prognostic Nutritional Index (PNI), and Geriatric Nutritional Risk Index (GNRI) were calculated at baseline. TF was defined as a permanent switch from PD to hemodialysis. Univariate and multivariate Cox regression was performed to investigate the association between confounding factors and outcomes. The optimal cut-off values were determined using receiver operating characteristic curve analysis. We used the Kaplan-Meier curve to compare the outcomes according to the cut-off values. The area under the curve (AUC) was used to test discriminative power of these objective nutritional indexes.

RESULTS

We analyzed 276 PD patients, 84 (30.43%) experienced TF during 2.5 (1.4, 4.0) years of follow-up. In the Kaplan-Meier analysis, patients with a higher CONUT score (>3), lower GNRI (≤85.77), and lower PNI (≤40.2) had significantly higher risk of TF (38.2% vs. 18.9%, P = .011; 39.6% vs. 25.1%, P = .043; 35.9% vs. 17.9%, P = .022; respectively). After adjusting confounding factors, a high CONUT score and low PNI were independently and significantly associated with TF analyzed by a multivariate Cox regression model (hazard ratio 2.284, 95% confidence interval [CI] 1.248-4.179, P = .007; hazard ratio 2.070, 95% CI 1.233-3.475, P = .006; respectively). The largest AUC to predict TF was PNI (AUC 0.600, 95% CI 0.539-0.658), followed by CONUT score (AUC 0.596, 95% CI 0.535-0.654) and GNRI (AUC 0.572, 95% CI 0.511-0.631).

CONCLUSIONS

The CONUT score and PNI are independently associated with TF in PD patients. Moreover, assessment of PNI and the CONUT score may provide more useful predictive values than GNRI.

Muscle mass change during chemotherapy in children with high-risk neuroblastoma: a retrospective case series of 24 patients

The clinical characteristics, cause, and risk factors of sarcopenia are unclear in children. The aim of this study was to describe the course of and identify the factors related to muscle mass change during chemotherapy in children with neuroblastoma. A total of 24 consecutive patients aged below 18 years with newly diagnosed high-risk neuroblastoma between 2010 and 2018 in our hospital were enrolled in a case-series study. The psoas muscle index (PMI) was calculated as a parameter of muscle mass based on computer tomography (CT) images of the psoas muscle. PMIs were evaluated at 4 time points (TPs): TP1, at the diagnosis of neuroblastoma; TP2, after the first cycle of chemotherapy; TP3, after the third cycle of chemotherapy; and TP4, at the end of the induction chemotherapy. PMI recovery was defined as an increase in PMI between TP2 and TP4. The mean PMI decreased by 15% between TP1 and TP2 (TP1 7.09 ± 0.99 vs. TP2 6.01 ± 0.98, P < 0.001) and by 10% between TP1 and TP4 (TP1 7.09 vs. TP4 6.35, P = 0.004). PMI recovery between TP1 and TP2 was observed in 7 (29%) patients. The median age of patients with PMI recovery was significantly lower (2 vs. 4 years, P = 0.028), and the proportion of boys was significantly higher in patients with PMI recovery (100% vs. 41%, P = 0.017).Conclusion: This study demonstrated that prominent PMI reduction occurs during the early time of chemotherapy, and a younger age and male sex may be predictive factors for PMI recovery. What is Known: • Sarcopenia is a common disorder in elderly people. • Several causes and risk factors have been reported in adults. • Children with previous hematological malignancies have decreased physical activity. What is New: • Prominent muscle mass loss was observed early in children with high-risk neuroblastoma during chemotherapy. • Age and sex were found to be potentially associated with muscle mass recovery.

Association Between Phase Angle and Sarcopenia in Patients Undergoing Peritoneal Dialysis

Introduction: There is limited data on the association between phase angle (PhA) and sarcopenia using both muscle strength and muscle mass in patients undergoing peritoneal dialysis (PD). We aimed to evaluate the association between PhA and sarcopenia in patients undergoing PD.

Methods: We enrolled prevalent patients undergoing PD (n = 200). The patients were divided into tertiles based on their PhA level: low (n = 66; 1.9–4°), middle (n = 68; 4.1–4.9°), and high tertiles (n = 66; 5–8°). PhA was measured by a bioimpedance analysis. Handgrip strength (HGS) was measured in all the patients. Body compositions were measured by dual energy x-ray absorptiometry (DXA).

Results: Handgrip strength (HGS) and/or lean mass indices showed poorer trends in the low tertile than in the other tertiles. PhA was positively associated with HGS and/or muscle mass index. Multivariate analyses showed that the patients in the low tertile had an odds ratio of 9.8 (p = 0.001) and 52.79 (p < 0.001) for developing sarcopenia compared with those in the middle and high tertiles, respectively. Subgroup analyses using these variables yielded results similar to those from the total cohort.

Conclusion: This study demonstrated that PhA is independently associated with muscle mass, strength, and sarcopenia in patients undergoing PD. This result suggests that PhA can be used as a valuable and simple predictor for identifying patients undergoing PD who are at risk of sarcopenia.

Synergic association of diabetes mellitus and chronic kidney disease with muscle loss and cachexia: results of a 16-year longitudinal follow-up of a community-based prospective cohort study

Muscle loss is a serious complication in patients with diabetes mellitus (DM) and chronic kidney disease (CKD). However, studies on a long-term change in muscle mass presence or absence of DM and CKD are scarce. We included 6247 middle-aged adults from the Korean Genome and Epidemiology Study (KoGES) between 2001 and 2016. Bioimpedance analysis (BIA) was performed biennially. Patients were classified into four groups according to the presence or absence of DM and CKD. The primary outcome was muscle depletion, which was defined as a decline in fat-free mass index (FFMI) below the 10th percentile of all subjects. The secondary outcomes included the occurrence of cachexia, all-cause mortality, and the slopes of changes in fat-free mass and weight. During 73,059 person-years of follow-up, muscle depletion and cachexia occurred in 460 (7.4%) and 210 (3.4%), respectively. In the multivariable cause-specific hazards model, the risk of muscle depletion was significantly higher in subjects with DM alone than in those without DM and CKD (HR, 1.37; 95% CI, 1.04-1.80) and was strongly pronounced in subjects with both conditions (HR, 3.38; 95% CI, 1.30-8.75). The secondary outcome analysis showed consistent results. The annual decline rates in FFMI, fat mass, and body mass index (BMI) were the steepest in subjects with DM and CKD among the four groups. DM and CKD are synergically associated with muscle loss over time. In addition, the mortality risk is higher in individuals with muscle loss.

Sarcopenia Is Associated with Mortality in Adults: A Systematic Review and Meta-Analysis

BACKGROUND

Sarcopenia can predispose individuals to falls, fractures, hospitalization, and mortality. The prevalence of sarcopenia depends on the population studied and the definition used for the diagnosis.

OBJECTIVE

This systematic review and meta-analysis aimed to investigate the association between sarcopenia and mortality and if it is dependent on the population and sarcopenia definition.

METHODS

A systematic search was conducted in MEDLINE, EMBASE, and Cochrane from 1 January 2010 to 6 April 2020 for articles relating to sarcopenia and mortality. Articles were included if they met the following criteria - cohorts with a mean or median age ≥18 years and either of the following sarcopenia definitions: Asian Working Group for Sarcopenia (AWGS and AWGS2019), European Working Group on Sarcopenia in Older People (EWGSOP and EWGSOP2), Foundation for the National Institutes of Health (FNIH), International Working Group for Sarcopenia (IWGS), or Sarcopenia Definition and Outcomes Consortium (SDOC). Hazard ratios (HR) and odds ratios (OR) were pooled separately in meta-analyses using a random-effects model, stratified by population (community-dwelling adults, outpatients, inpatients, and nursing home residents). Subgroup analyses were performed for sarcopenia definition and follow-up period.

RESULTS

Out of 3,025 articles, 57 articles were included in the systematic review and 56 in the meta-analysis (42,108 participants, mean age of 49.4 ± 11.7 to 86.6 ± 1.0 years, 40.3% females). Overall, sarcopenia was associated with a significantly higher risk of mortality (HR: 2.00 [95% CI: 1.71, 2.34]; OR: 2.35 [95% CI: 1.64, 3.37]), which was independent of population, sarcopenia definition, and follow-up period in subgroup analyses.

CONCLUSIONS

Sarcopenia is associated with a significantly higher risk of mortality, independent of population and sarcopenia definition, which highlights the need for screening and early diagnosis in all populations.

Relationship between Vascular Calcification, Protein-Energy Wasting Syndrome, and Sarcopenia in Maintenance Automated Peritoneal Dialysis

Vascular calcifications affect 80% to 90% of chronic kidney disease patients and are a predictive factor of cardiovascular mortality. Sarcopenia and protein-energy wasting syndrome are also associated with mortality. The aim was to assess the relationship between vascular calcification, sarcopenia, and protein-energy wasting syndrome (PEW) in automated peritoneal dialysis patients. Fifty-one maintenance automated peritoneal dialysis patients were included (27 were male, mean age 39 ± 14 years). Vascular calcification was assessed based on abdomen, pelvis, and hand radiographs. Sarcopenia was assessed with bioimpedance analysis and a hand grip strength test. The Malnutrition-Inflammation Score and the presence of PEW were also assessed. Vascular calcification was present in 21 patients (41.2%). Univariate logistic regression analysis showed that age (p = 0.001), Malnutrition-Inflammation Score (p = 0.022), PEW (p = 0.049), sarcopenia (p = 0.048), and diabetes (p = 0.010) were associated with vascular calcification. Multivariate logistic regression analysis showed that age (p = 0.006) was the only variable associated independently with vascular calcification. In conclusion, there is association between vascular calcification, PEW, and sarcopenia in patients with maintenance automated peritoneal dialysis. These associations are not independent of age. This demonstrates the importance of nutritional status in the prevention of vascular calcification.

Validation of the SARC-F for Assessing Sarcopenia in Patients on Peritoneal Dialysis

OBJECTIVE

Proper screening or diagnosis of sarcopenia (SP) is important to obtain favorable outcomes in patients on peritoneal dialysis (PD). Previous studies have shown that the SARC-F is associated with various parameters of SP in elderly populations. In this study, we aimed to validate the SARC-F questionnaire for predicting SP in patients on PD.

METHODS

This cross-sectional study was conducted at a tertiary medical center. We identified all patients prevalent on PD patients (n = 127). A version of the original SARC-F was used to assess the questionnaire. Patients with a total score of ≥4 points were defined as the high group and those with <4 points were defined as the normal group. The hand grip strength and appendicular skeletal muscle mass index were measured in all patients. SP was defined as previously reported.

RESULTS

Of the 127 total patients, 29 (22.8%, high group) had an SARC-F score of ≥4. The sensitivity and specificity of the SARC-F for predicting SP were 70.0% and 81.2%, respectively. The negative predictive and positive predictive values were 96.9% and 24.1%, respectively. The area under curve of the SARC-F score for SP was 0.791 (0.709-0.858, P < .001). The hand grip strength of the normal and high groups was 26.4 ± 8.5 and 19.5 ± 6.8 kg, respectively (P < .001). The appendicular skeletal muscle mass index in the normal and high groups was 7.6 ± 1.3 and 7.2 ± 1.8 kg/m², respectively (P = .152). An increase in the SARC-F score as a continuous variable or classification into the high group as a categorical variable was associated with a higher odds ratio for SP in univariate and multivariate analyses.

CONCLUSION

The SARC-F has a high negative predictive value and a high specificity for predicting SP in patients on PD.