Complete low-intensity endurance training programme in haemodialysis patients: improving the care of renal patients.

BACKGROUND: Patients on haemodialysis (HD) have a decreased physical and functional capacity. Several studies have reported the beneficial effects of exercise on the physical, functional and psychological functioning of HD patients. Despite these results, exercise programmes on HD are not commonplace. OBJECTIVE: To analyse the effect of an intradialysis endurance training programme on muscular strength and functional capacity in our HD patients. MATERIAL AND METHODS: A 6-month single-centre prospective study. HD patients were non-randomly assigned to an exercise group (group E) or a control group (group C). Exercise training included complete endurance training using balls, weights and elastic bands in the first 2 h of an HD session; group C received standard HD care. Analysed data: (1) biochemical parameters; (2) biceps and quadriceps muscle tone, maximum quadriceps length strength (MQLS) and dominant hand grip (HG); (3) functional capacity tests: sit-to-stand-to-sit (STS10) and 6-min walking test (6MWT). RESULTS: Forty patients were included, 55% were men; their mean age was 68.4 years; the patients were 61.6 months on HD; 16 patients were in group E and 24 in group C. In group E, muscular strength showed a significant improvement in MQLS (15.6 ± 10.7 vs. 17.7 ± 12.5 kg, p < 0.05) and HG (22.1 ± 13.2 vs. 24.1 ± 15.8 kg, p < 0.05) at the end of the programme, while a global decrease was reported in group C (MQLS 20.9 ± 9.3 vs. 16.2 ± 8.4 kg, p < 0.05; HG 25.1 ± 10.3 vs. 24.1 ± 11.1 kg). 6MWT significantly improved in group E (20%, 293.1 vs. 368 m, p < 0.001) and decreased in group C (10%, 350 vs. 315 m, p < 0.004). At the end of the programme, STS10 time was reduced in group E (2.1 ± 18.5 vs. 28.7 ± 20.6 s), while it rose in group C (31.5 ± 17.9 vs. 36.4 ± 19.8 s), though significant differences were not found. CONCLUSIONS: (1) The intradialysis training programme improved muscular strength and functional capacity in our HD patients. (2) These results support the benefits of exercise training for HD patients. (3) Nephrologists should consider exercise training as a standard practice for the care of HD patients.

Is fetuin-A a biomarker of dialysis access dysfunction?

BACKGROUND: The arteriovenous (AV) access function of hemodialysis (HD) patients can be impaired by afferent artery stiffness due to preexisting microcalcification and by venous stenosis secondary to neointimal hyperplasia in whose development participates an upregulated local inflammatory process. Fetuin-A is a circulating potent inhibitor of vascular calcification and plays an important anti-inflammatory role. The aims of this prospective study were to investigate the relationship between baseline serum fetuin-A levels and: blood flow (QA) values at baseline, AV access failure (thrombosis or intervention for stenosis) during follow-up and primary unassisted AV access patency. METHODS: We measured baseline serum fetuin-A levels and QA values of the AV access in 64 HD patients under routine QA surveillance for stenosis. Patients were classified into tertiles according to their baseline fetuin-A levels (g/L): <0.5 (tertile-1), 0.5-1.20 (tertile-2), and >1.20 (tertile-3). RESULTS: Fetuin-A was positively correlated with QA (Spearman coefficient = 0.311, p = 0.012). Fourteen patients (21.9%) underwent AV access failure and they had lower fetuin-A (0.59 ± 0.32 g/L) and lower QA (739.4 ± 438.8 mL/min) values at baseline compared with the remaining patients (1.05 ± 0.65 g/L and 1273.0 ± 596.3 mL/min, respectively) (p = 0.027 and p < 0.001, respectively). The AV access failure rate was highest (34.8%) in tertile-1 (lowest fetuin-A level). Unadjusted Cox regression analysis showed a decrease in the risk of AV access patency loss by increasing fetuin-A concentration (hazard ratio 0.395 (95% confidence interval: 1.42-1.69), p = 0.044) but it was not confirmed in the adjusted model, although the hazard ratio was low (0.523). Kaplan-Meier analysis showed that patients in tertile-3 (highest fetuin-A concentration) had the highest primary unassisted AV access patency (λ2 = 4.68, p = 0.030, log-rank test). CONCLUSION: If our results are confirmed in further studies, fetuin-A could be used as a circulating biomarker to identify HD patients at greater risk for AV access dysfunction, who would benefit from much closer dialysis access surveillance.

The search for a new marker of renal function in older patients with chronic kidney disease stages 3-4: usefulness of cystatin C-based equations.

BACKGROUND/AIM: Cystatin C (Cys C) is an endogenous marker of glomerular filtration rate (GFR) unaffected by body composition. The aim of the present study was to assess the utility of Cys C-based GFR prediction equations (Hoek, Larsson and Stevens) and creatinine (modification of diet in renal disease-isotope dilution mass spectrometry--MDRD-IDMS, and Cockcroft-Gault--CG) compared with 51Cr-EDTA. METHODS: This study was carried out in 40 Caucasian older patients with advanced age (> or = 60) and chronic kidney disease stages 3-4. To assess the utility of prediction equations in relation to body composition, we measured lean mass (LM) with densitometry (DXA). Pearson's, Bland-Altman and Lin's coefficient (Rc) were used to study accuracy and precision. RESULTS: 51Cr-EDTA was 36.9 +/- 9.2 ml/min/1.73 m2 (22-60). Cys C levels were 2.2 +/- 0.8 mg/l (r = 0.085; p = 0.662 LM) and creatinine 2.8 +/- 1.1 mg/dl (r = 0.427; p = 0.021 LM). The most accurate equations were the Hoek, Larsson and Stevens formulae, with a bias of -0.2 (Rc 0.48), -2.9 (Rc 0.44) and 2.6 ml/min/1.73 m2 (Rc 0.58). The biases obtained with MDRD-IDMS and CG were -14.6 (Rc 0.35) and -12.5 (Rc 0.40). All correlations among biases obtained with creatinine-based formulae and LM were negative and statistically significant (p < 0.05). CONCLUSIONS: The results show superiority of Cys C-based GFR formulae over the MDRD-IDMS and CG equations. This significant underestimation obtained with conventional prediction equations was directly related to the influence of LM.

Effects of rotigotine on clinical symptoms, quality of life and sleep hygiene adequacy in haemodialysis-associated restless legs syndrome. / Efectos de la rotigotina sobre la sintomatología, calidad de vida e higiene de sueño en el síndrome de piernas inquietas en hemodiálisis.

BACKGROUND: Restless legs syndrome (RLS) is a neurological disorder characterised by bothersome symptoms associated with impaired quality of life and sleep hygiene. Rotigotine is a novel therapeutic alternative, although few studies have been published in patients on haemodialysis (HD) with RLS treated with rotigotine. OBJECTIVES: 1.- To establish the prevalence of RLS in our HD unit. 2.- To evaluate the efficacy and safety profile of rotigotine and its effect on symptoms, quality of life and sleep hygiene in our HD population with RLS. MATERIAL AND METHODS: A single-centre, 12-week prospective study. Two stages (6 weeks): stage 1 (no treatment) and stage 2 (rotigotine). We analysed: 1.- Demographic data, biochemistry data, HD suitability parameters and RLS medical treatment data. 2.- Lower extremity symptoms questionnaire (QS). 3.- RLS severity symptoms scale (SRLSS). 4.- RLS Quality of life: John Hopkins RLS-QoL (JH-QoL). 5.- Sleep hygiene: SCOPA Scale. RESULTS: We included 66 HD patients, 14 with RLS; 44.4% male, 70.2±9.9 years and 111.1±160.8 months on HD. And 22.9% RLS. Exclusively in stage 2, a significant improvement for QS (10±2.4 vs. 5.7±1.0), SRLSS (21±4 vs. 5.7±4.6), JH-QoL (22.1±4.4 vs. 4.3±4.0) and SCOPA (16±5.3 vs. 6.7±1.9) were observed. A 77.7 and 11.1%, showed partial (> 20%) and complete (> 80%) remission, respectively, while 55.5% achieved «zero¼ symptoms. Only one patient had gastrointestinal intolerance and none experienced augmentation effect. No changes in biochemical data, suitability for dialysis or medical treatment were found. The inter-group analysis showed a significant improvement in relation to QS, SRLSS, JH-QoL and SCOPA in stage 2. CONCLUSIONS: RLS showed a considerable prevalence in our HD unit. Rotigotine improved clinical symptoms, quality of life and sleep hygiene in RLS patients on HD and was found to be a safe drug with minimal side effects and total therapeutic compliance. Nevertheless, future studies should be performed to confirm the benefits of rotigotine in RLS patients on haemodialysis.

The effect of neuromuscular electrical stimulation on muscle strength, functional capacity and body composition in haemodialysis patients. / Efecto de la electroestimulación neuromuscular sobre la fuerza muscular, capacidad funcional y composición corporal en los pacientes en hemodiálisis.

INTRODUCTION: Haemodialysis (HD) patients are characterised by significant muscle loss. Recently, neuromuscular electrical stimulation (NMES) has emerged as a new therapeutic alternative to improve these patients' physical condition. To date, no studies on the effects of NMES on body composition in HD patients have been published. OBJECTIVE: To analyse the effect of NMES on muscle strength, functional capacity and body composition in our HD patients. MATERIAL AND METHODS: A 12-week, single-centre, prospective study. The patients were assigned to an electrical stimulation (ES) or control (CO) group. The ES group was subjected to intradialytic electrical stimulation of the quadriceps (Compex® Theta 500i), while the CO group received standard HD care. We analysed the following: 1) nutritional parameters; 2) muscle composition of the quadriceps; 3) maximum quadriceps extension strength (mes) and hand-grip (HG); 4) «sit to stand to sit¼ (STS10) and «six-minute walking test¼ (6MWT); 5) body composition (bioelectrical impedance analysis). RESULTS: Of 20 patients, 55% were men. Mean age 67.7 years, 30.3 months in HD. Main aetiology: DM (35%). In the ES group were 13 patients, and 7 in the CO group. At the end of the study, an improvement was only observed in the ES group (*P<.05): MES* (11.7±7.1 vs. 13.4±7.4kg), STS10 (39.3±15.5 vs. 35.8±13.7s) and 6MWT* (9.9%, 293.2 vs. 325.2m). Furthermore, increased quadriceps muscle area (QMA*: 128.6±30.2 vs. 144.6±22.4cm2) and lowered quadriceps fat area (QFA*: 76.5±26.9 vs. 62.1±20.1cm2) were observed. No relevant changes in body composition, nutritional parameters and dialysis adequacy were found. CONCLUSIONS: 1) NMES improved muscle strength, functional capacity and quadriceps muscle composition in our patients. 2) Based on the results obtained, NMES could be a new therapeutic alternative to prevent muscle atrophy and progressive physical deterioration. 3) However, future studies are necessary to establish the potential beneficial effects of NMES in HD patients.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis. / Guía Clínica Española del Acceso Vascular para Hemodiálisis.

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

Benefits of a low intensity exercise programme during haemodialysis sessions in elderly patients.

BACKGROUND: Elderly patients on haemodialysis (HD) are a steadily increasing group. They show a high complexity, dependency and comorbidity. Multiple benefits from exercise in HD patients have been reported; however, they have not been specifically evaluated in an elderly population. OBJECTIVE: To assess the effect of an adapted low intensity intradialytic exercise programme on muscle strength, functional capacity and health-related quality of life in our elderly patients (> 80 years) on HD. MATERIAL AND METHODS: HD patients were non-randomly assigned to an exercise training group (E) or a control group (C) in a 12-week single-centre prospective study. E included a combined exercise programme using balls, weights, elastic bands and cycle movements in the first 2 hours of HD sessions. C group patients received standard HD care. Endpoints were: 1) main biochemical data; 2) maximum quadriceps length strength (MQLS) and hand-grip (HG); 3) functional capacity tests: "Sit to stand to sit" (STS10) and "six-minutes walking test" (6MWT); 4) Beck Depressive Inventory (BDI); and 5) Health-related quality of life questionnaire: EuroQol-5D (EQ-5D). RESULTS: A total of 22 patients were included (50% men). Mean age was 83.2 years; patients had received HD for 44.1 month. Charlson index was 9.5. Main aetiology was diabetes mellitus (36.4%). Eleven patients were assigned to E group and 11 to C group. No related adverse effects were observed. At the end of the study, E group showed an overall improvement in tests (*P<.05): MQLS 10.5 ± 7.6 vs. 12.9 ± 10.1 kg, HG* 16.6 ± 8.7 vs. 18.2 ± 8.9 kg, STS10* 29.9 ± 10.6 vs. 25 ± 7.87 sec, 6MWT* 14.6%, 234.4 vs. 274.7 m, BDI* 14.4 ± 11.5 vs. 11.7 ± 10.8 and EQ-5D 49 ± 19.1 vs. 59.5 ± 20.3. No similar changes were observed in C group. Significant differences between groups were also found for HG, MQLS, STS10, 6MWT, BDI and EQ-5D. No significant changes were found in biochemical and anthropometric data, antidepressant treatment or suitable dialysis parameters at the end of the study. CONCLUSIONS: 1) An adapted low intensity exercise programme improved muscle strength, functional capacity and health-related quality of life in our elderly patients on HD. 2) Our results highlight the benefits from exercise in HD patients even in this elderly population. 3) In elderly patients on HD, it is worth considering an adapted low intensity intradialytic exercise programme as a part of a comprehensive care.