Association of Sarcopenia With Nutritional Parameters, Quality of Life, Hospitalization, and Mortality Rates of Elderly Patients on Hemodialysis

Sarcopenia diagnosis using different criteria as a predictor of early mortality in patients undergoing hemodialysis

OBJECTIVES

Chronic kidney disease (CKD) is a public health problem, causing secondary sarcopenia. The aim of this study was to evaluate sarcopenia using the definitions proposed by European Working Group on Sarcopenia in Older People in 2010 (EWGSOP₂₀₁₀) and 2019 (EWGSOP₂₀₁₉) as an independent prognostic factor for worse survival in patients with CKD undergoing hemodialysis.

METHODS

Muscle mass, muscle strength, and physical performance were assessed in a cohort of patients with CKD on hemodialysis. The sample consisted of 127 patients (40% >60 y of age) and 36 patients (28.3%) died after a median follow-up length of 23.5 mo (interquartile range= 14.9 - 29). The EWGSOP₂₀₁₀ and EWGSOP₂₀₁₉ definitions were used for diagnosing sarcopenia. Sarcopenia association with mortality by both definitions was investigated using Kaplan-Meier curves and Cox proportional hazard models. The area under the curve, sensitivity, specificity, positive, and negative predictive values for both definitions were also compared.

RESULTS

Patients diagnosed with sarcopenia by both criteria had almost three times higher risk for mortality (95% confidence interval,1.45-6.06 and 1.44-6.13, respectively). Patients classified with severe sarcopenia by both definitions had a significantly lower survival, even after the adjusted analysis. The areas under the curve for EWGSOP₂₀₁₀ and EWGSOP₂₀₁₉ did not significantly differ. The sensitivity/specificity analysis was considered similar for both criteria, and around 70% of the patients was correctly classified.

CONCLUSION

Sarcopenia, notably severe sarcopenia, diagnosed by EWGSOP₂₀₁₀ or EWGSOP₂₀₁₉ criteria, is an independent prognostic factor for worse survival in this population. Early detection with effective interventions may decrease the higher mortality risk among patients with sarcopenia and CKD.

Is malnutrition a determining factor of health-related quality of life in hemodialysis patients? A cross-sectional design examining relationships with a comprehensive assessment of nutritional status

PURPOSE

To identify relationships between health-related quality of life (HRQOL) and nutritional status in hemodialysis (HD) patients.

METHOD

Secondary data from a cross-sectional survey was utilized. HRQOL was assessed for 379 HD patients using the generic Short Form 36 (SF-36) and disease-specific Kidney-Disease Quality of Life-36 (KDQOL-36). Malnutrition was indicated by malnutrition inflammation score (MIS) ≥ 5, and presence of protein-energy wasting (PEW). The individual nutritional parameters included the domains of physical status, serum biomarkers, and dietary intake. Multivariate associations were assessed using the general linear model.

RESULTS

MIS ≥ 5 was negatively associated with SF-36 scores of physical functioning (MIS < 5 = 73.4 ± 8.0 SE vs MIS ≥ 5 = 64.6 ± 7.7 SE, P < 0.001), role-limitation-physical (MIS < 5 = 65.3 ± 14.3 SE vs MIS ≥ 5 = 52.9 ± 14.0 SE, P = 0.006), general health (MIS < 5 = 53.7 ± 7.5 SE vs MIS ≥ 5 = 47.0 ± 7.1 SE, P = 0.003), and PCS-36 (MIS < 5 = 40.5 ± 3.3 SE vs MIS ≥ 5 = 35.9 ± 3.1 SE, P < 0.001); and KDQOL-36 score of symptoms/problems (MIS < 5 = 78.9 ± 5.6 SE vs MIS ≥ 5 = 74.8 ± 5.4 SE, P = 0.022), but not with PEW by any tool. Of individual nutritional parameters, underweight (68.1 ± 5.4 SE, P = 0.031), normal weight (63.8 ± 2.8 SE, P = 0.023), and overweight (64.3 ± 2.9 SE, P = 0.003) patients had significantly higher physical functioning scores compared to obese patients (44.8 ± 5.5 SE). Serum albumin levels were positively associated with physical functioning (P = 0.041) score. HGS was also positively associated with physical functioning (P = 0.036), and vitality (P = 0.041) scores. Greater dietary phosphorus intakes were significantly associated with lower scores for role limitation-physical (P = 0.008), bodily pain (P = 0.043), and PCS-36 (P = 0.024).

CONCLUSION

Malnutrition diagnosis by MIS, but not PEW, indicated associations with HRQOL in HD patients. Individual nutritional parameters that related to higher HRQOL were BMI < 30 kg/m², better dietary phosphorus control, greater muscle strength and higher visceral protein pool.

Geriatric nutritional risk index in prediction of muscular strength of elderly patients undergoing hemodialysis

PURPOSE

Geriatric nutritional risk index (GNRI) is one of the new tools to determine nutritional status in the elderly. This study assessed the association between GNRI and muscular strength through handgrip strength (HGS) in patients undergoing hemodialysis.

METHODS

This cross-sectional analytical study assessed 110 hemodialysis patients at Guilan, North of Iran, (mean age of 70.3 ± 6.93), 57 men and 53 women through simple random sampling. Demographic characteristics, GNRI, and HGS of patients were determined. Data were analyzed using descriptive and inferential statistics, including independent t test, AVOVA, Pearson correlation, and linear multiple regression tests.

RESULTS

The mean values of the GNRI and HGS were 93.90 ± 11.06 and 14.82 ± 3.72, respectively. Finally, it was identified that there is a direct and significant association between GNRI and HGS (p = 0.001, r = 0.734). Linear multiple regression showed that GNRI is an independent predictor of HGS (Adj.R² = 0.67, β_GNRI = 8.13).

CONCLUSION

GNRI can be used as a predictor of muscular strength in hemodialysis patients.

Association of Serum Phosphate with Low Handgrip Strength in Patients with Advanced Chronic Kidney Disease

Muscle wasting and hyperphosphatemia are becoming increasingly prevalent in patients who exhibit a progressive decline in kidney function. However, the association between serum phosphate (Pi) level and sarcopenia in advanced chronic kidney disease (CKD) patients remains unclear. We compared the serum Pi levels between advanced CKD patients with (n = 51) and those without sarcopenia indicators (n = 83). Low appendicular skeletal muscle mass index (ASMI), low handgrip strength, and low gait speed were defined per the standards of the Asian Working Group for Sarcopenia. Mean serum Pi level was significantly higher in advanced CKD patients with sarcopenia indicators than those without sarcopenia indicators (3.88 ± 0.86 vs. 3.54 ± 0.73 mg/dL; p = 0.016). Univariate analysis indicated that serum Pi was negatively correlated with ASMI, handgrip strength, and gait speed. Multivariable analysis revealed that serum Pi was significantly associated with handgrip strength (standardized β = -0.168; p = 0.022) and this association persisted even after adjustments for potential confounders. The optimal serum Pi cutoff for predicting low handgrip strength was 3.65 mg/dL, with a sensitivity of 82.1% and specificity of 56.6%. In summary, low handgrip strength is common in advanced CKD patients and serum Pi level is negatively associated with handgrip strength.

Low skeletal muscle mass by computerized tomography is associated with increased mortality risk in end-stage kidney disease patients on hemodialysis

BACKGROUND AND AIMS

Skeletal muscle (SM) area, as measured by abdominal CT at the level of the third lumbar vertebra (L3), has been proposed as a proxy of whole body muscle mass. However, population-specific reference values are lacking. In the present study we aimed at: (1) detecting low SM area on abdominal CT images in patients on hemodialysis by applying cut-offs derived from a group of healthy subjects, and (2) estimating the independent risk of all-cause mortality associated with low SM area.

METHODS

We retrospectively enrolled 212 adult patients on hemodialysis, undergoing abdominal CT scan (study group), and 87 healthy kidney donors (reference group). We obtained the gender-specific 5th percentile values of the abdominal SM area distribution from both the whole control group and the subgroup of younger (29-60 years) subjects, which we used as reference cut-offs. Then we applied those cut-offs in the study group to identify patients with low SM area. We used survival and Cox regression analysis to evaluate the risk of all-cause mortality associated with low abdominal SM area.

RESULTS

In the fully adjusted Cox regression analysis, the patients with low abdominal SM area had a higher risk of death than the patients with values above the reference cut-off derived in the subgroup of younger controls (adjHR = 1.79 (1.21; 2.67), P = 0.004).

CONCLUSIONS

Abdominal CT imaging can be used to detect low abdominal SM area in patients on hemodialysis by applying cut-offs derived from healthy subjects sharing a similar ethnic background. Low SM area as assessed by CT is independently associated with all-cause mortality in ESKD patients on hemodialysis.

Malnutrition and Sarcopenia Combined Increases the Risk for Mortality in Older Adults on Hemodialysis

Aim: Sarcopenia and malnutrition are highly prevalent in older adults undergoing hemodialysis (HD) and are associated with negative outcomes. This study aimed to evaluate the role of sarcopenia and malnutrition combined on the nutritional markers, quality of life, and survival in a cohort of older adults on chronic HD. Methods: This was an observational, longitudinal, and multicenter study including 170 patients on HD aged >60 years. Nutritional status was assessed by 7-point-subjective global assessment (7p-SGA), body composition (anthropometry and bioelectrical impedance), and appendicular skeletal muscle mass (Baumgartner's prediction equation). Quality of life was assessed by KDQoL-SF. The cutoffs for low muscle mass and low muscle strength established by the 2019 European Working group on sarcopenia for Older People (EWGSOP) were used for the diagnosis of sarcopenia. Individuals with a 7p-SGA score ≤5 were considered malnourished, individuals with low strength or low muscle mass were pre-sarcopenic, and those with low muscle mass and low muscle strength combined as sarcopenic. The sample was divided into four groups: sarcopenia and malnutrition; sarcopenia and no-malnutrition; no-sarcopenia with malnutrition; and no-sarcopenia and no-malnutrition. Follow-up for survival lasted 23.5 (12.2; 34.4) months. Results: Pre-sarcopenia, sarcopenia, and malnutrition were present in 35.3, 14.1, and 58.8% of the patients, respectively. The frequency of malnutrition in the group of patients with sarcopenia was not significantly higher than in the patients without sarcopenia (66.7 vs. 51.2%; p = 0.12). When comparing groups according to the occurrence of sarcopenia and malnutrition, the sarcopenia and malnutrition group were older and presented significantly lower BMI, calf circumference, body fat, phase angle, body cell mass, and mid-arm muscle circumference. In the survival analysis, the group with sarcopenia and malnutrition showed a higher hazard ratio 2.99 (95% CI: 1.23: 7.25) for mortality when compared to a group with no-sarcopenia and no-malnutrition. Conclusion: Older adults on HD with sarcopenia and malnutrition combined showed worse nutritional parameters, quality of life, and higher mortality risk. In addition, malnutrition can be present even in patients without sarcopenia. These findings highlight the importance of complete nutritional assessment in patients on dialysis.

Usefulness of computed tomography-measured psoas muscle thickness per height for predicting mortality in patients undergoing hemodialysis

Computed tomography (CT)-measured psoas muscle thickness standardized for height (PMTH) has emerged as a promising predictor of mortality. The study aimed to investigate whether PMTH could accurately predict mortality in patients undergoing hemodialysis. We examined 207 patients (mean age: 63.1 years; men: 66.2%) undergoing hemodialysis for more than 6 months in hospital affiliated clinic. PMTH was calculated at the L3 vertebra level using CT. Patients were divided according to the PMTH cut-off points: 8.44 mm/m in women and 8.85 mm/m in men; thereafter, they were combined into low and high PMTH groups. PMTH was independently correlated with the simplified creatinine index (β = 0.213, P = 0.021) and geriatric nutritional risk index (β = 0.295, P < 0.0001) in multivariate regression analysis. During a median follow-up of 3.7 (1.8–6.4) years, 76 patients died, including 41 from cardiovascular causes. In the multivariate Cox regression analysis, low PMTH (adjusted hazard ratio, 2.48; 95% confidence interval, 1.36–4.70) was independently associated with an increased risk of all-cause mortality. The addition of binary PMTH groups to the baseline risk model tended to improve net reclassification improvement (0.460, p = 0.060). In conclusion, PMTH may be an indicator of protein energy wasting and a useful tool for predicting mortality in patients undergoing hemodialysis.

Association Between the Normal-Density Psoas Muscle Index and Handgrip Strength or Gait Speed in Maintenance Hemodialysis Patients

Introduction: This study aimed to evaluate the association between the psoas muscle (PM) index with or without fatty infiltration and various indices associated with muscle mass in hemodialysis (HD) patients.

Methods: We included stable HD patients (n = 83). The collected data included subjective global assessment (SGA) score, ASM/Ht² (appendicular skeletal muscle mass divided by the squared height in meters), gait speed (GS; m/s), and handgrip strength (HGS; kg). The abdominal computed tomography (CT) image was obtained using a CT scanner. The PM and normal-density PM (NPM) indices (mm²/m²) were calculated using the whole PM area or the area with an attenuation range of 35–100 HU divided by the squared height in meters.

Results: Correlation coefficients for the SGA score, ASM/Ht², HGS, and GS were greater for the NPM index than for the PM index. The linear regression analysis showed that, on multivariate analysis, the NPM index was significantly associated with the SGA score, ASM/Ht², and GS. However, the PM index was significantly associated with the SGA score and ASM/Ht² but not with HGS or GS. For calculating the low GS, the area under the receiver operating characteristic curve area was significantly greater for the NPM index than for the PM index (P = 0.012).

Conclusion: The present study suggested that the NPM index excluding fatty infiltration may be an early and useful indicator for detecting muscle strength and physical performance among HD patients.

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.

Can conditions of skeletal muscle loss be improved by combining exercise with anabolic-androgenic steroids? A systematic review and meta-analysis of testosterone-based interventions

Sarcopenia, cachexia, and atrophy due to inactivity and disease states are characterized by a loss of skeletal muscle mass, often accompanied by reduced levels of anabolic hormones (e.g. testosterone). These conditions are associated with an increase in mortality, hospitalization and worsening in quality of life. Both physical exercise (EX) and anabolic-androgenic steroid (AAS) administration can improve the prognosis of patients as they increase physical functionality. However, there is a gap in the literature as to the impact of these therapies on the gains in strength and muscle mass and their implications for patient safety. Accordingly, we performed a random-effects meta-analysis to elucidate the effects of AAS and/or EX interventions on lean body mass (LBM) and muscle strength in conditions involving muscle loss. A systematic search for relevant clinical trials was conducted in MEDLINE, EMBASE, SCOPUS, Web of Science, and SPORTDiscus. Comparisons included AAS vs. Control, EX vs. Control, AAS vs. EX, AAS + EX vs. AAS and AAS + EX vs. EX. A total of 1114 individuals were analyzed. AAS increased LBM (effect size [ES]: 0.46; 95% CI: 0.25, 0.68, P = 0.00) and muscle strength (ES: 0.31; 95% CI: 0.08, 0.53, P = 0.01) when compared to a control group. EX promoted an increase in muscular strength (ES: 0.89; 95% CI: 0.53, 1.25, P = 0.00), with no effect on LBM when compared to the control group (ES: 0.15; 95% CI: -0.07, 0.38, P = 0.17). AAS did not demonstrate statistically significant differences when compared to EX for LBM and muscle strength. The combination of EX + AAS promoted a greater increase in LBM and muscular strength when compared to AAS or EX in isolation. Qualitatively, AAS administration had relatively few side effects. Significant heterogeneity was found in some analyses, which may be explained by the use of different AAS types and EX protocols. Our findings suggest that AAS administration in cachectic and sarcopenic conditions may be a viable interventional strategy to enhance muscle function when exercise is not a possible approach. Moreover, combining AAS with exercise may enhance positive outcomes in this population.

Uremic Sarcopenia and Its Possible Nutritional Approach

Uremic sarcopenia is a frequent condition present in chronic kidney disease (CKD) patients and is characterized by reduced muscle mass, muscle strength and physical performance. Uremic sarcopenia is related to an increased risk of hospitalization and all-causes mortality. This pathological condition is caused not only by advanced age but also by others factors typical of CKD patients such as metabolic acidosis, hemodialysis therapy, low-grade inflammatory status and inadequate protein-energy intake. Currently, treatments available to ameliorate uremic sarcopenia include nutritional therapy (oral nutritional supplement, inter/intradialytic parenteral nutrition, enteral nutrition, high protein and fiber diet and percutaneous endoscopic gastrectomy) and a personalized program of physical activity. The aim of this review is to analyze the possible benefits induced by nutritional therapy alone or in combination with a personalized program of physical activity, on onset and/or progression of uremic sarcopenia.

Hopelessness and Depression Predict Sarcopenia in Advanced CKD and Dialysis: A Multicenter Cohort Study

BACKGROUND/OBJECTIVES

Depression and hopelessness are frequently experienced in chronic kidney disease (CKD) and are generally associated with lessened physical activity. The aim of this study was to quantify the associations between sarcopenia as determined by SARC-F with both depression and hopelessness.

DESIGN AND SETTING

This multicenter cohort study involving cross-sectional and longitudinal analyses was conducted in a university hospital and four general hospitals, each with a nephrology center, in Japan.

PARTICIPANTS

Participants consisted of 314 CKD patients (mean age 67.6), some of whom were receiving dialysis (228, 73%).

MEASUREMENTS

The main exposures were depression, measured using the Center for Epidemiologic Studies Depression (CES-D) questionnaire, and hopelessness, measured using a recently developed 18-item health-related hope scale (HR-Hope). The outcomes were sarcopenia at baseline and one year after, measured using the SARC-F questionnaire. Logistic regression models were applied.

RESULTS

The cross-sectional and longitudinal analyses included 314 and 180 patients, respectively. Eighty-nine (28.3%) patients experienced sarcopenia at baseline, and 44 (24.4%) had sarcopenia at the one-year follow-up. More hopelessness (per 10-point lower, adjusted odds ratio [AOR]: 1.33, 95% confidence interval [95% CI] 1.12-1.58), depression (AOR: 1.87, 95% CI 1.003-3.49), age (per 10-year higher, AOR: 1.70, 95% CI 1.29-2.25), being female (AOR: 2.67, 95% CI 1.43-4.98), and undergoing hemodialysis (AOR, 2.92; 95% CI, 1.41-6.05) were associated with a higher likelihood of having baseline sarcopenia. More hopelessness (per 10-point lower, AOR: 1.69, 95% CI 1.14-2.51) and depression (AOR: 4.64, 95% CI: 1.33-16.2) were associated with a higher likelihood of having sarcopenia after one year.

CONCLUSIONS

Among patients with different stages of CKD, both hopelessness and depression predicted sarcopenia. Provision of antidepressant therapies or goal-oriented educational programs to alleviate depression or hopelessness can be useful options to prevent sarcopenia.

Design and methodology of the Aging Nephropathy Study (AGNES): a prospective cohort study of elderly patients with chronic kidney disease

BACKGROUND

Renal replacement therapy (RRT) is usually indicated for patients with chronic kidney disease (CKD) with glomerular filtration rate below 10 ml/ml/min/1.73m². However, the need for RRT and timing of dialysis initiation are debatable for patients aged 70 years or older. We here describe the study design and methodology of the Aging Nephropathy Study (AGNES) protocol that aims at evaluating to what extent geriatric-related conditions such as frailty, cognitive dysfunction, and presence of comorbidities have an impact on survival and RRT initiation in this group of patients. In this manuscript we provide detailed information about the AGNES study design and methodology.

METHODS

AGNES is a prospective observational cohort that aim to investigate clinical, biochemical and demographic factors associated with RRT initiation and mortality of patients with CKD stage 4 or 5 who are aged 70 years and older. We plan to include 200 patients over 5 years. Clinically stable outpatients on conservative management for at least 6 months will be recruited from the Nephrogeriatric Clinic at the Hospital das Clinicas da Universidade de Sao Paulo, Brazil. Eligible patients are submitted to a full clinical examination, geriatric assessment, and blood test at baseline. Following the baseline visit the patients are being monitored during an observational follow up period of at least 12 months during which patients will be contacted in the clinic at their regular follow up or by phone until either RRT initiation or death occurs. This cohort includes evaluation of cognition by the education-adjusted 10-point Cognitive Screener (10-CS), frailty by Fried index score, a complete nutritional assessment (by body composition assessment, global subjective assessment and dietary intake), comorbidities by Charlson comorbidity index and biochemical markers including FGF-23 and Klotho.

DISCUSSION

The AGNES cohort, a real-world study of current clinical practice in elderly patients with advanced CKD prior to dialysis initiation, will shed light into progression of CKD and its complications, indications of RRT and factors determining survival. This investigation will elucidate to what extent geriatric conditions, nutritional status and clinical factors are associated with survival, quality of life and RRT initiation in elderly CKD patients not yet on dialysis.

TRIAL REGISTRATION

Registered on ClinicalTrials.gov on 18 October 2019 ( NCT04132492 ).

Skeletal Muscle Index as a Prognostic Marker for Kidney Transplantation in Older Patients

OBJECTIVE

Low skeletal muscle mass has emerged as a risk factor for mortality after liver transplantation. We evaluated the prognostic value of muscle mass on length of hospitalization and adverse outcomes after kidney transplantation in aging end-stage renal disease patients.

METHODS

One hundred twenty-two patients aged 60 years or older at the time of transplantation were retrospectively analyzed. Skeletal muscle index (SMI), evaluated by computed tomography scan, was calculated from total muscle surface area at L3 vertebral level divided by body height squared. Outcomes were compared according to SMI (namely, length of hospitalization, wound complications, combined endpoint comprising all-cause mortality, and graft failure within 1 year).

RESULTS

In male patients, by multivariate analysis, a low SMI (<42 cm²/m²) was associated with longer immediate post-transplantation hospitalization (β = 17.03 ± 4.3; P = .0002), longer total hospitalization during the first year (β = 34.3 ± 10.7; P = .002), higher rate of wound complications (odds ratio = 12.1 [1.9-77.0]; P = .008), and higher rate of the combined endpoint of graft loss or death (odds ratio = 3.4 [3.0-399.5]; P = .004). In female patients, low SMI was not associated with length of hospitalization or adverse outcomes after transplantation.

CONCLUSION

SMI is an independent marker of morbidity and mortality after kidney transplantation in older men and could help thereby nephrologists better select aging candidates for kidney transplantation with a view to improving post-transplant outcomes.

The cut-off values of handgrip strength and lean mass index for sarcopenia among patients on peritoneal dialysis

Background

Sarcopenia is common and contributes to a high risk of mortality among general population. There is no consensus regarding the cut-off values for sarcopenia in terms of mortality among chronic kidney disease patients. This study aimed to explore and validate cut-off points of handgrip strength (HGS) and lean mass index (LMI) for estimating the risk of mortality in peritoneal dialysis (PD) patients.

Methods

This single-center prospective cohort study enrolled 1089 incident PD patients between October 2002 and July 2019. All patients were followed until death, transfer to hemodialysis, receiving renal transplantation or the end date of study (December 2019). All participants were randomly sampled to development cohort (70% participants) and validation cohort (30% participants), matched by gender and diabetes. Lean body mass was calculated by using the equation published by our center. Cubic spline regression analysis was used to examine the relationship between HGS or LMI values and mortality, and explore the cut-off points after adjusting for age, diabetes, cardiovascular disease and serum albumin in the development cohort. The derived cut-off values were verified by the agreement rate for predicting mortality and then compared with cut-off values from various clinical guidelines in the validation cohort.

Results

All 1089 patients were followed up with the median of 36.0 (18.0, 71.0) months. In the development cohort, cut-off points for predicting the higher mortality were derived as 24.5 kg and 14 kg of HGS for males and females, 16.7 kg/m² and 13.8 kg/m² of LMI for males and females respectively. In the validation cohort, these cut-off values significantly predicted worse outcomes, with HR 1.96 (1.35, 2.84) of HGS and HR 1.76 (1.26, 2.47) of LMI for all-cause mortality after multivariate adjustment. The newly derived cut-off points of HGS have numerically higher prognostic values in all-cause mortality compared with those from current clinical guidelines, and agreement rates of HGS were 65.2 versus 62.5–64.6 respectively.

Conclusions

The derived cut-off values of HGS and LMI have sufficient and better prognostic value in predicting all-cause mortality in PD patients compared with the cut-off values in the existing guidelines. These cut-off values are only validated in a single population, thus limiting the generalizability.

MicroRNA molecules as predictive biomarkers of adaptive responses to strength training and physical inactivity in haemodialysis patients

The miRNA-206 and miRNA-23a play an important role in muscle tissue hypertrophy, regeneration and atrophy. Both of these miRNAs have been highlighted as promising adaptation predictors; however, the available evidence on associations is inconclusive. Therefore, our aim was to assess the expression levels of these two miRNAs as predictors of change in muscle function during strength training and physical inactivity among dialysed patients. For this purpose, 46 haemodialysis patients were monitored for 12-weeks of either intradialytic strength training (EXG, n = 20) or physical inactivity during dialysis (CON, n = 26). In both groups of patients, we assessed the baseline expression levels of miRNA-23a and miRNA-206 and the isometric force generated during hip flexion (HF) contraction before and after the 12-week period. Among the EXG group, the expression of miRNA-206 predicted the change in HF (R² = 0.63, p = 0.0005) much more strongly than the expression of miRNA-23a (R² = 0.21, p = 0.027). Interestingly, baseline miRNA-23a (R² = 0.30, p = 0.006) predicted the change in HF much more than miRNA-206 (p = ns) among the CON group. Our study indicates that the baseline expression of miRNA-206 could predict the response to strength training, while miRNA-23a could serve as a potential predictive marker of functional changes during physical inactivity in dialysis patients.

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

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

Sarcopenia and inflammation in patients undergoing hemodialysis

Introduction

Introduction: in individuals with chronic kidney disease, sarcopenia is prevalent and is associated with increased morbidity and mortality, and the occurrence of cardiovascular complications. Objective: to verify the relationship between sarcopenia and inflammation in hemodialysis patients. Methods: a cross-sectional study with 209 patients in five hemodialysis units. Demographic, socioeconomic, body composition, clinical laboratory, and functional data were collected. Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People (grip strength < 27 kg for men and < 16 kg for women; DEXA muscle mass < 7.0 kg/m² for men and < 5.5 kg/m² for women). Inflammation was assessed by C-reactive protein. Results: mean age was 51.9 ± 15.0 years, with a predominance of males (59.3 %). The prevalence of sarcopenia was 29.1 % and that of inflammation was 50.2 %. A Poisson regression analysis showed that sarcopenia was associated with increased hsCRP values (PR: 1.06; 95 % CI: 1.01-1.10; p-value = 0.005); BMI (PR: 0.74; 95 % CI: 0.65-0.84; p-value < 0.001); age (PR: 1.02; 95 % CI: 1.00-1.03; p < 0.001); male (PR: 5.75; 95 % CI: 3.20-10.34; p-value < 0.001); presence of diabetes mellitus (DM) (PR: 1.87; 95 % CI: 1.27-2.74; p-value < 0.001); % body fat (PR: 1.07; 95 % CI: 1.04-1.09; p-value < 0.001). Conclusion: the prevalence of sarcopenia can be considered high in this study, as well as inflammation. Being inflamed, presence of DM, being male, increasing age, and % body fat were risk factors for sarcopenia. On the other hand, increased BMI had a protective role.

Changes in Quality of Life in Older Hemodialysis Patients: A Cohort Study on Dialysis Outcomes and Practice Patterns

BACKGROUND

Despite improvements in dialysis treatment, mortality rates remain high, especially among older hemodialysis patients. Quality of life (QOL) among hemodialysis patients is strongly associated with higher risk of death. This study aimed to describe the health-related QOL and its change in older maintenance hemodialysis patients and to demonstrate characteristics associated with health-related QOL.

METHODS

Data on 892 maintenance hemodialysis patients aged 60 years or older who were surveyed using the Kidney Disease Quality of Life Short Form at baseline and 2 years after study enrollment in phases 4 (2009-2011) and 5 (2012-2014) of the Japanese Dialysis Outcomes and Practice Patterns Study were analyzed. We categorized participants into 3 age groups (60-69, 70-79, and ≥80 years) and described baseline physical component summary (PCS) and mental component summary (MCS) scores, as well as their distribution of changes after 2 years across each category.

RESULTS

Hemodialysis patients aged 70-79 years and ≥80 years had lower PCS scores than those aged 60-69 years (median: 70-79 years = 43.1; interquartile range [IQR], 35.2-49.4; ≥80 years = 38.8; IQR, 31.6-43.8; 60-69 years = 45.4; IQR, 37.5-51.4; p < 0.001). In contrast, MCS scores did not significantly differ by age category (70-79 years = 45.6; IQR, 38.4-53.7; ≥80 years = 45.4; IQR, 36.9-55.1; 60-69 years = 46.8; IQR, 39.5-55.7; p = 0.1). As dialysis vintage lengthened, the PCS score significantly became lower, whereas no association was found with change in the MCS score. The MCS score declined over time in older patients, especially among those aged 80 years and older after 2 years' follow-up.

CONCLUSIONS

Physical QOL became worse as dialysis vintage lengthened. In contrast, mental QOL declined over time within a relatively short period among older maintenance hemodialysis patients.

The prevalence of temporomandibular disorders in chronic hemodialysis patients: a cross-sectional study

Objective: This study aimed to investigate the prevalence of temporomandibular disorders (TMD) in patients with chronic hemodialysis and evaluate the risk factors of developing TMD.Methods: One hundred forty-six subjects were included in the study. The examination for TMD was based on the standardized Research Diagnostic Criteria for Temporomandibular Disorders. Axis I protocol was used to evaluate the prevalence of TMD sub-diagnoses.Results: The prevalence of TMD was 41.5% in hemodialysis patients and significantly higher than in the control group. The most common symptom was TMJ pain, and the most common TMD subtype was muscular type. Female patients had significantly higher TMD than males. C-reactive protein, hemoglobin, parathyroid hormone, and albumin were significantly associated with TMD.Conclusion: There was an elevated prevalence of TMD in hemodialysis patients.

Effects of volume status on body composition in incident peritoneal dialysis patients

BACKGROUND

Inadequate fluid removal or high water intake leads to overhydration, which results in malnutrition. The aim of the present study was to evaluate the effects of volume status on body composition in incident peritoneal dialysis (PD) patients.

METHODS

All incident PD patients who survived ≥1 year after PD initiation were considered eligible. A total of 366 incident PD patients were finally included and divided into three tertiles according to the time-averaged-edema index (TA-EI). The body composition parameters measured using bioimpedance analysis included the EI, fat mass index (FMI, kg/m²), and appendicular muscle mass index (AMMI, kg/m²). dFMI and dAMMI were defined as delta values for each variable. The cutoff value for sarcopenia (SP) was defined as previously reported. Patients with AMMI below the cutoff values were defined as having SP.

RESULTS

The number of participants in the low, middle, and high tertiles was 126, 100, and 140, respectively. A high volume status was associated with high solute clearance, albumin loss, and glucose absorption through the peritoneal membrane, which led to high dialysate glucose. In addition, volume status was inversely associated with increases in AMMI, but was not associated with changes in FMI. SP as a categorical variable was positively associated with a high volume status. On subgroup analyses, TA-EI had the greatest negative correlation coefficients for dAMMI.

CONCLUSION

Overhydration in PD patients was associated with decrease in muscle mass indices and the development of SP.

Modified creatinine index and risk for long-term infection-related mortality in hemodialysis patients: ten-year outcomes of the Q-Cohort Study

Modified creatinine (Cr) index, calculated by age, sex, pre-dialysis serum Cr concentration, and Kt/V for urea, is an indicator of skeletal muscle mass in hemodialysis (HD) patients. It remains unknown whether the modified Cr index predicts infection-related mortality in this population. We investigated the association between the modified Cr index and infection-related mortality. A total of 3046 patients registered in the Q-Cohort Study, a multicenter, observational study of HD patients, were analyzed. Associations between sex-specific quartiles (Q1–Q4) of the modified Cr index and the risk for infection-related mortality were analyzed by Cox proportional hazard model. During a median follow-up of 8.8 years, 387 patients died of infection. The estimated risk for infection-related mortality was significantly higher in the lower quartiles (Q1, Q2, and Q3) than in the highest quartile (Q4) as the reference group (hazard ratios and 95% confidence intervals [CI]: Q1, 2.89 [1.70–5.06], Q2, 2.76 [1.72–4.62], and Q3, 1.79 [1.12–2.99]). The hazard ratio (95% CI) for a 1 mg/kg/day decrease in the modified Cr index was 1.18 (1.09–1.27, P < 0.01) for infection-related mortality. In conclusion, a lower modified Cr index is associated with an increased risk for long-term infection-related mortality in the HD population.

New-Onset Diabetes Mellitus in Peritoneal Dialysis and Hemodialysis Patients: Frequency, Risk Factors, and Prognosis-A Review

New-onset diabetes mellitus (NODM) is observed in both hemodialysis (HD) and peritoneal dialysis (PD) patients. The prevalence of NODM in dialysis patients is slightly higher compared to subjects of the general population. Based on currently published data there is no convincing evidence that the risk of NODM is different between HD and PD patients. Data on the effect of glucose load on risk of NODM in dialysis patients remain controversial. PD modality (automated or continuous ambulatory PD) has no significant influence on NODM incidence. Chronic inflammation is associated with NODM in dialysis patients. Reported differences in NODM between PD and HD patients are possibly also influenced by differences in demographic factors between these patient groups. Mortality in NODM patients is lower than mortality in patients with preexisting DM. This may be partly explained by the younger age and lower number of comorbidities in patients with NODM.

The relationship between antecedent creatinine decreases and outcomes in patients undergoing hemodialysis

INTRODUCTION

Previous studies have demonstrated an association between low serum creatinine levels and adverse outcomes in patients undergoing maintenance hemodialysis. However, little is known regarding whether long-term changes in serum creatinine predict outcomes independently and incrementally over a single point evaluation.

METHODS

Serum creatinine data at index (June 2013) and for the 18 months prior to the index blood sampling (between January 2012 and June 2013) were evaluated in 346 hemodialysis patients. Patients were followed from the index blood sampling for primary (all-cause mortality) and secondary (cardiovascular death) endpoints.

FINDINGS

During a median follow-up of 5.7 years, there were 82 all-cause and 25 cardiovascular deaths. Compared to patients who survived, those who died displayed a greater time-dependent reduction in creatinine levels during the 18 months prior to the index assessment, coupled with a greater decrease in predialysis body weight (interaction p = 0.007). Patients who displayed creatinine decline over the prior 18 months (∆ creatinine<0 mg/dL) had higher all-cause mortality than those who maintained creatinine levels (∆ creatinine≥0 mg/dL). After adjustment for clinical factors and baseline creatinine index, antecedent creatinine decrease was independently associated with an increased risk of all-cause mortality, with an incremental prognostic value over baseline creatinine index alone. A reduction in creatinine levels was also associated with cardiovascular death independent of the baseline creatinine index.

DISCUSSION

A long-term antecedent decrease in serum creatinine levels is independently associated with clinical outcomes in hemodialysis patients, with an incremental prognostic value over baseline creatinine index alone. Our data suggest that serial creatinine measurements are a useful prognosticator in practice.

Nutritional Aspects in Diabetic CKD Patients on Tertiary Care

Background and objectives: Diabetes is largely prevalent in the chronic kidney disease (CKD) population. Both conditions have metabolic and nutritional abnormalities that affect body composition and the presence of diabetes makes the dietary management of CKD patients more difficult. The aim of this study was to assess peculiar nutritional and functional aspects of diabetic patients in an adult/elderly CKD population, and their predictive significance. Materials and methods: This prospective cohort study included 144 out-patients aged >55 years, affected by stage 3b-4 CKD, on tertiary care clinic; 48 (40 males) were type 2 diabetics and 96 (80 males) were nondiabetics. The two groups have similar age, gender, and residual renal function (30 ± 9 vs. 31 ± 11 mL/min×1.73). All patients underwent a comprehensive nutritional and functional assessment and were followed for 31 ± 14 months. Results: Diabetic CKD patients showed higher waist circumference and fat body mass, lower muscle mass, and lower number of steps per day and average daily METs. Meanwhile, resting energy expenditure (REE), as assessed by indirect calorimetry, and dietary energy intake were similar as well as hand-grip and 6 min walking test. Diabetic patients did not show a greater risk for all-cause mortality and renal death with respect to nondiabetics. Middle arm muscle circumference, phase angle, serum cholesterol, and serum albumin were negatively related to the risk of mortality and renal death after adjustment for eGFR. Conclusions: CKD diabetic patients differed from nondiabetics for a greater fat mass, lower muscle mass, and lower physical activity levels. This occurred at the same REE and dietary energy intake. The outcome of diabetic or nondiabetic CKD patients on tertiary care management was similar in terms of risk for mortality or renal death. Given the same residual renal function, low levels of muscle mass, phase angle, serum albumin, and cholesterol were predictive of poor outcome. Overall, a malnutrition phenotype represents a major predictor of poor outcome in diabetic and nondiabetic CKD patients.

Association of sarcopenic obesity with the risk of all-cause mortality among adults over a broad range of different settings: a updated meta-analysis

Background

Previous cohort studies investigating the association between sarcopenic obesity (SO) and all-cause mortality among adult people have been inconsistent. We performed a meta-analysis to determine if SO is a predictor of all-cause mortality.

Methods

Prospective cohort studies that evaluated the association between SO and mortality in older people were identified via a systematic search of three electronic databases (PubMed, EMBASE, and the Cochrane Library). A random-effects model was applied to combine the results. We considered the methods recommeded by consensuses (dual X-ray absorptiometry,bio-impedancemetry, anthropometric measures or CT scan) to assess sarcopenic obesity.

Results

Of the 603 studies identified through the systematic review, 23 (Participants: 50866) were included in the meta-analysis. The mean age ranged from 50 to 82.5 years.SO was significantly associated with a higher risk of all-cause mortality among adult people (pooled HR = 1.21, 95% confidence interval [95% CI] = 1.10–1.32, p < 0.001, I² = 64.3%). Furthermore, the subgroup analysis of participants showed that SO was associated with all-cause mortality (pooled HR = 1.14, 95% CI: 1.06–1.23) among community-dwelling adult people; similarly, this association was found in hospitalized patients (pooled HR = 1.65, 95% CI: 1.17–2.33). Moreover, the subgroup analysis demonstrated that SO was associated with all-cause mortality when using skeletal muscle mass (SMM) criteria, muscle strength criteria, and skeletal muscle index (SMI) criteria (HR = 1.12, 95% CI: 1.01–1.23; HR = 1.18, 95% CI: 1.05–1.33; and HR = 1.53, 95% CI: 1.13–2.07, respectively). In addition, we analyzed SO on the basis of obesity definition and demonstrated that participants with a SO diagnosis based on waist circumference (WC) (HR = 1.24, 95% CI: 1.09–1.40), body mass index (BMI) (HR = 1.29, 95% CI: 1.04–1.59), or visceral fat area (HR = 2.54, 95% CI: 1.83–3.53) have a significantly increase mortality risk compared with those without SO.

Conclusion

Based on our update of existing scientific researches, SO is a significant predictor of all-cause mortality among older people, particularly hospitalized patients. Therefore, it is important to diagnose SO and to treat the condition to reduce mortality rates among older people.

Electronic supplementary material

The online version of this article (10.1186/s12877-019-1195-y) contains supplementary material, which is available to authorized users.

Predictive value of percentage body fat in aging people with low muscle mass: A 2.2-year longitudinal study

BACKGROUND

The aim of this study was to evaluate the usefulness of percentage body fat (PBF) in screening for the risk of low muscle mass (LMM) in elderly people.

METHODS

A prospective study was carried out in Chinese PLA General Hospital with 413 participants who underwent baseline and an average 2.2-year follow-up health check-up examinations.

RESULTS

The average age of the participants at baseline was 63.6 years. The incidence of newly developed LMM was 10.3% in men and 18.2% in women during follow-up. Linear regression demonstrated that baseline PBF were negatively correlated with follow-up total muscle mass index (TMMI) in both men and women (β=-0.124 for men and -0.233 for women, all P < 0.001). The cut-off points of baseline PBF in elderly people for future LMM were 25.45% in men and 30.95% in women and were identified by Receiver Operator Curves (ROC).

CONCLUSIONS

Elderly people with a high PBF had a higher risk of new LMM, which suggested that baseline PBF had a close relationship with future LMM and the screening of high PBF should be paid enough attention in health care management in the senior people.

Prevalence and Correlates of Sarcopenia among Elderly CKD Outpatients on Tertiary Care

Background: Sarcopenia is a widespread concern in chronic kidney disease (CKD) as well in elderly patients and is one of the main reasons why low-protein diets for this population are controversial. The aim of this study was to assess the prevalence and correlates of sarcopenia among elderly male patients affected by CKD followed up in an outpatient nephrology clinic, where moderate protein restriction (0.6–0.8 g/Kg/day) is routinely recommended to patients in CKD stage 3b-5 not on dialysis. Methods: This observational study included 80 clinically-stable male out-patients aged >60, affected by stage 3b-4 CKD. Forty patients aged ≥75 (older seniors) were compared to the other forty patients aged 60–74 (younger seniors). All patients underwent a comprehensive nutritional and functional assessment. Results: Older seniors showed lower serum albumin, hand-grip strength, body mass index (BMI), skeletal muscle mass, and resting energy expenditure. Protein intake was significantly lower in older seniors whereas energy intake was similar. Average daily physical activity was lower in the older seniors than in the younger ones. Sarcopenia was more prevalent in older than in younger seniors. Among older seniors, sarcopenic and non-sarcopenic ones differed in age and performance on the Six-Minute Walk test, whereas the estimated glomerular filtration rate (eGFR), biochemistry, dietary protein, and energy intakes were similar. Conclusions: Older senior CKD male patients have lower muscle mass, muscle strength, and physical capacity and activity levels, with a higher prevalence of sarcopenia than younger patients. This occurs at the same residual renal function and metabolic profile and protein intake. Energy intake was at the target in both subgroups. In this CKD cohort, sarcopenia was associated with age and physical capacity, but not with eGFR or dietary intakes.

Association between Geriatric Nutrition Risk Index and low muscle mass in Chinese elderly people

BACKGROUND/OBJECTIVES

The aim of the study was to evaluate the relationship between Geriatric Nutrition Risk Index (GNRI) and low muscle mass (LMM) in elderly people.

SUBJECTS/METHODS

A cross-sectional study was carried out in Chinese PLA General Hospital with 3240 participants who underwent a health check-up examination between February 2016 and February 2017. Linear regression and logistic regression were used to examine the relationship between GNRI and LMM.

RESULTS

The mean age of the participants in the study was 64.6 years. The mean appendicular skeletal muscle mass index (ASMI) was 8.92 ± 0.93 kg/m² in men and 7.62 ± 0.73 kg/m² in women. The incidences of LMM were 7.9% in men and 3.7% in women. Linear regression demonstrated that GNRIs were positively correlated with ASMIs in both men and women (β = 0.055 for men and 0.039 for women, all P < 0.001). The cut-off point of the GNRI in elderly people for LMM was 104.0 in men and 107.0 in women and were identified by Classification and Regression Trees (CART). Logistic regression showed that both men and women with decreased GNRIs had higher ratios of LMM [odds ratio (OR) = 3.904 for men and 4.486 for women, P < 0.001 and P = 0.001, respectively].

CONCLUSIONS

Elderly people with a low GNRI had a higher incidence of LMM, which suggested that GNRI had a close relationship with LMM and that it could be a good indicator in identifying senior people who need further nutritional support and physical activity.

Muscle mass assessment by computed tomography in chronic kidney disease patients: agreement with surrogate methods

BACKGROUND/OBJECTIVES

Patients with chronic kidney disease (CKD) are subjected to muscle wasting. Therefore, it is important to investigate surrogate methods that enable the assessment of muscle mass loss in the clinical setting. We aimed to analyze the agreement between computed tomography (CT) and surrogate methods for the assessment of muscle mass in non-dialysis CKD patients.

SUBJECTS/METHODS

Cross-sectional study including 233 non-dialysis patients on CKD stages 3 to 5 (61 ± 11 years; 64% men; glomerular filtration rate 22 (14-33) mL/min/1.73 m²). The muscle mass was evaluated by CT and bioelectrical impedance, skinfold thicknesses, midarm muscle circumference (MAMC), the predictive equations of Janssen and Baumgartner and the physical examination of muscle atrophy from the subjective global assessment.

RESULTS

In males, the MAMC showed the best agreement with CT as indicated by the kappa test (k = 0.57, P < 0.01), sensitivity (S = 68%), specificity (S = 89%) and accuracy (area under the curve-AUC = 0.78), followed by the Baumgartner equation (kappa = 0.46, P < 0.01; sensitivity = 60%; specificity = 87% and AUC = 0.73). In female, the Baumgartner equation showed the best agreement with CT (kappa = 0.43, P < 0.01; sensitivity = 57%; specificity = 86% and AUC = 0.71).

CONCLUSIONS

The MAMC and Baumgartner equation showed the best agreement with CT for the assessment of muscle mass in non-dialysis CKD patients.