Sarcopenia diagnosed by ultrasound-assessed quadriceps muscle thickness and handgrip strength predicts mortality in patients on hemodialysis.

BACKGROUND: Estimation of muscle mass is a pivotal component in the diagnosis of protein-energy wasting and sarcopenia. While bioimpedance spectroscopy is a widely  accepted technique for the assessment of lean tissue related to the diagnosis of sarcopenia, to date skeletal muscle ultrasound (US) has not gained full acceptance for this purpose. The aim of this study was to assess the predictive value for mortality of the indexed thickness of the quadriceps vastus intermedius, as measured by US, compared to lean tissue index as estimated by bioimpedance spectroscopy, both combined with handgrip strength in a group of patients with end-stage kidney disease (ESKD) on maintenance hemodialysis (HD). METHODS: The cut-off values for low handgrip strength were < 27 kg for males and < 16 kg for females. The cut-off value for low lean tissue index was obtained from an age-matched healthy control group, with low lean tissue index being defined as values below the 10th percentile of the distribution of healthy subjects. The cut-off values for low quadriceps vastus intermedius thickness index were < 3.44 mm/m2 for males and < 3.52 mm/m2 for females. RESULTS: Ultrasound and bioimpedance spectroscopy were performed in 99 patients, and handgrip strength was assessed in 64 patients, all on maintenance HD. After a median follow-up of 28 months (interquartile range 19-41 months) 38 patients died. Lean tissue index was not associated with mortality, while low quadriceps vastus intermedius thickness index and low handgrip strength were associated with an increased hazard of death. In the fully adjusted model, only the combination of low handgrip strength and low quadriceps vastus intermedius thickness index was significantly associated with higher mortality. CONCLUSION: When combined with low handgrip strength, low quadriceps muscle US outperformed low lean tissue index as assessed by bioimpedance spectroscopy in predicting mortality in a cohort of patients on maintenance HD. Ultrasound may be a useful and convenient technique for the assessment of sarcopenia and protein-energy wasting in this patient population.

Physical activity and exercise programs for kidney patients: an Italian survey of nephrology centres.

BACKGROUND: Data on exercise activities in place, and on the interest for developing them in Nephrology Services in Italy is limited. To address this gap, we carried out this cross-sectional study to investigate the status of physical activity and exercise programs available in Italian Nephrology Centres. Additionally, research priorities on this topic were examined. METHODS: We developed a 14-item electronic survey, which consisted of multiple-choice questions covering exercise training programs, physical assessment, barriers to exercise practice and to exercise programs, exercise and physical activity counselling practices, perceived exercise benefits, literature evidence, and research priorities. Data on the characteristics of the centres were also collected. RESULTS: Sixty-two responses from Italian nephrology centres were collected. Ninety-three percent of the respondents were aware of the scientific evidence supporting the benefits of regular exercise programs for chronic kidney disease (CKD) patients. Additionally, in 75% of centres the nephrologists believed that physical activity counselling should be performed by the nephrologists. However, only 26% of centres provided exercise programs, mainly for dialysis patients, and 63% never or infrequently assessed physical activity in the context of patient management. Eighty-nine percent of centres reported barriers to implementing exercise programs, including lack of funding, institutional disinterest, patient refusal, and negative attitudes of the healthcare personnel. Forty-six research priorities related to exercise in CKD patients were suggested, with the majority focusing on impact of exercise programs and physical activity on cardiovascular, nutritional, and psychosocial outcomes. CONCLUSION: This survey highlights the limited availability of exercise programs and physical activity evaluation in clinical practice in Italian Nephrology Centres. However, the survey also revealed a strong interest for counselling CKD patients on physical activity and implementing exercise prescriptions and interventions.