Concomitant sarcopenia and undernutrition: Impact on clinical outcomes in patients undergoing hemodialysis.

BACKGROUND: Sarcopenia and undernutrition are crucial in the cycle of frailty in patients requiring hemodialysis therapy, and their deleterious clinical consequences are well documented. However, little attention has been directed towards examining their combined impact on clinical outcomes. OBJECTIVE: This study aimed to elucidate the effects of concomitant sarcopenia and undernutrition on clinical outcomes in patients undergoing hemodialysis. METHODS: This prospective cohort study recruited outpatients undergoing hemodialysis from four facilities. Sarcopenia was diagnosed according to the criteria of the Asian Working Group for Sarcopenia, 2019. Undernutrition was determined using the Geriatric Nutritional Risk Index, with a score of <92 classified as undernutrition. Patients were classified into four groups according to the presence or absence of sarcopenia and undernutrition. Cox proportional hazards analysis was used to assess the independent association between concomitant sarcopenia and undernutrition, all-cause mortality, and cardiovascular (CV) events after adjusting for baseline characteristics. RESULTS: We included 450 patients in this analysis. Of the 450 patients, 69 (15.3%) had concomitant sarcopenia and undernutrition. The mean follow-up period was 1067 days, and there were 61 deaths and 60 CV events. The cumulative survival rate was significantly lower in the sarcopenia with undernutrition group (P = 0.011). The overlap of sarcopenia and undernutrition was significantly associated with a risk of mortality (hazard ratio 2.10; 95% confidence interval 1.05-4.21; P = 0.037). However, no association was observed between the co-occurrence of sarcopenia and undernutrition and the risk of CV events. CONCLUSIONS: Concomitant sarcopenia and undernutrition were significantly associated with an increased mortality risk among patients undergoing hemodialysis. This finding reaffirms the importance of managing sarcopenia and undernutrition in patients undergoing hemodialysis in daily clinical practice.

Simplified discriminant parameters for sarcopenia among patients undergoing haemodialysis.

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

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

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