Physical Exercise in Kidney Renal Recipients: Where Have We Come?

BACKGROUND: Kidney transplantation constitutes the most effective therapeutic option for patients suffering from end-stage renal disease but remains burdened by a high incidence of cardiovascular disease. To date, exercise is an important preventive strategy that has been underestimated; in kidney transplant patients, exercise programs lead to an improvement in cardiorespiratory performance, muscle strength, arterial stiffness, and patients' quality of life perception. SUMMARY: The nephrology and transplant community have moved from generic suggestions to specific indications regarding frequency, intensity, time, type, volume, and progression of physical exercise both in the pre- and posttransplant phase. The latest guidelines from the World Health Organization for patients with chronic conditions propose a combination of aerobic, muscle-strengthening, and multicomponent exercises (e.g., balance) to improve health. Based on recent evidence, a combined exercise program (aerobic and strength exercise) is largely proposed to kidney transplant recipients. Aerobic exercise should be performed at an intensity >60% of theoretical maximum heart rate or maximum oxygen uptake possibly every day, and strength training should be performed at a >60% the estimate single maximum repetition, at least 2 times per week. KEY MESSAGES: Physical exercise should be personalized in relation to the patient's baseline performance; increases must be progressive and gradual. Regular physical activity should also be recommended to patients awaiting for a transplant. Eventually, organizational models based on a network of nephrology units, transplant centers, sports medicine centers, and fitness center or outdoor gym are essential elements for overcoming the logistical barriers for prescribing and carrying out regular physical activity.

Testimonies and experiences of patients awaiting transplant and transplanted patients in Italy: a survey aiming to understand their needs.

INTRODUCTION AND METHODS: In 2020 the Italian National Transplant Centre (Centro Nazionale Trapianti, Istituto Superiore di Sanità, Rome, Italy) launched two online surveys to explore waitlisted and transplanted patients' needs. RESULTS: The analysis of two-year results shows prevailing feelings of anxiety and discouragement (44.5%) in waitlisted patients. A mere 19.7% expresses feelings of trust and hope. Conversely, in transplanted patients, gratitude (65.7%) predominates. Both transplanted (53.5%) and waitlisted patients (41.5%) worry about organ rejection and complications, SARS-CoV-2 pandemic was an additional concern. The latter report certainty of transplant as their main need (81.3%), followed by psychological support (41.8%) also indicated by 27.9% of transplanted patients, while donor-recipient anonymity is an issue for 31.3% of the transplanted. CONCLUSION: Focusing on the needs and, above all, taking them on, means putting the patient at the centre of care and increasing the chances of a better life despite sufferings and preoccupations.

Effects of combined strength and endurance training on exercise capacity in kidney transplant cyclists and runners.

INTRODUCTION: After transplantation, engaging in regular physical activity (PA) or sport is recommended for health. Participation to competitive sports is increasingly common among kidney transplant recipients while little is known on how training affects the physical performance in transplanted athletes. AIM: The purpose of this case study was to assess the effects of a tailored training program on exercise parameters in kidney transplant cyclists (CKTRs) and runners (RKTRs). METHODS: Twelve male transplanted athletes were enrolled. The workload at aerobic and anaerobic thresholds, the submaximal aerobic power (V'O2 stage) and rate of perceived exertion (RPE) during an incremental cycling or running test, and the peak instantaneous force (PIF) during a countermovement jump were assessed at baseline (T0) and after 6 months of tailored training (T6) consisting in strength and aerobic exercises. Exercise adherence, blood lipid profile and renal function were also investigated. RESULTS: Eight CKTRs and 4 RKTRs completed the 6-month training period, with a significant increase of training volume (minutes/week). The exercise adherence was met by 90% in both groups. At T6, there were significant (p<0.05) improvements of maximum workload attained, the workload corresponding to the aerobic threshold and PIF, while workloads at anaerobic threshold, V'O2 stage and RPE were unchanged. Blood cholesterol significantly decreased (p<0.01), while the other blood parameters were unchanged. CONCLUSIONS: These findings indicate that the combined strength and endurance training is well tolerated and may improve exercise performance in this selected population of KTRs.

Access of non-residents to transplantation of deceased donor organs: practices and strategies in the European setting.

The access of non-resident patients to the deceased donor waiting list (DDWL) poses different challenges. The European Committee on Organ Transplantation of the Council of Europe (CD-P-TO) has studied this phenomenon in the European setting. A questionnaire was circulated among the Council of Europe member states to inquire about the criteria applied for non-residents to access their DDWL. Information was compiled from 28 countries. Less than 1% of recipients of deceased donor organs were non-residents. Two countries never allow non-residents to access the DDWL, four allow access without restrictions and 22 only under specific conditions. Of those, most give access to non-resident patients already in their jurisdictions who are in a situation of vulnerability (urgent life-threatening conditions). In addition, patients may be given access: (i) after assessment by a specific committee (four countries); (ii) within the framework of official cooperation agreements (15 countries); and (iii) after patients have officially lived in the country for a minimum length of time (eight countries). The ethical and legal implications of these policies are discussed. Countries should collect accurate information about residency status of waitlisted patients. Transparent criteria for the access of non-residents to DDWL should be clearly defined at national level.

Physical activity and renal function in the Italian kidney transplant population.

BACKGROUND: The well-documented benefits of physical activity (PA) are still poorly characterized in long-term kidney transplant outcome. This study analyzed the impact over a 10-year follow-up of PA on graft function in Italian kidney transplant recipients (KTRs). METHODS: Since 2002, the Italian Transplant-Information-System collected donor and recipient baseline and transplant-related parameters in KTRs. In 2015, 'penchant for PA' (PA ≥ 30-min, 5 times/week) was added. Stable patients aged ≥18 years at the time of first-transplantation were eligible. KTRs with at least 10-year follow-up were also analyzed. Mixed-effect regression models were used to compare eGFR changes over time in active versus non-active patients. RESULTS: PA information was available for 6,055 KTRs (active 51.6%, non-active 48.4%). Lower penchant for PA was found in overweight and obese patients (OR = 0.84; OR = 0.48, respectively), in those with longer dialysis vintage (OR = 0.98 every year of dialysis), and older age at transplant. Male subjects showed greater penchant for PA (OR = 1.25). A slower decline of eGFR over time was observed in active KTRs compared to non-active, and this finding was confirmed in the subgroup with at least 10-year follow-up (n = 2,060). After applying the propensity score matching to reduce confounding factors, mixed-effect regression models corroborated such better long-term trend of graft function preservation in active KTRs. CONCLUSIONS: Penchant for PA is more frequent among male and younger KTRs. Moreover, in our group of Italian KTRs, active patients revealed higher eGFR values and preserved kidney function over time, up to 10-years of follow-up.

Observational Retrospective Study on Patient Lifestyle in the Pretransplantation and Post-transplantation Period in the Emilia-Romagna Region.

INTRODUCTION: Despite the well-known benefits of exercise during the pretransplantation and post-transplantation phases, adherence to active lifestyles is still reduced. The aim of the present study is to evaluate how many patients who have received organ transplants and candidates for organ transplantation carry out physical or sports activities in order to increase adherence to an active lifestyle. METHODS: The patients who agreed to participate in the study were interviewed about their lifestyle habits by the staff at the nephrology, dialysis, and hepatology units of the Emilia-Romagna region. The interview investigated the patient's lifestyle (active or sedentary) and type of physical activity (walking, cycling, gardening, gym at least 3 to 40 minutes, 2 to 3 times per week) or sport (training > 2 times per week) routinely practiced. RESULTS: We collected 1138 interviews from patients on the waiting list (n = 159) for organ transplant, those with kidney transplants (n = 756), and those with liver transplants (n = 223) monitored in the Emilia-Romagna hospitals (regional patients 67%, extraregional 33%). Eighty-four patients on the waiting list for a transplant (kidney) were sedentary, 75 practiced physical activity, and 10 of 75 physically active patients practiced sport. Four hundred fifteen patients with kidney transplants were sedentary, 341 practiced physical activity, and 31 of 341 physically active patients practiced sport. Among patients with liver transplants, 56 were sedentary, 167 practiced physical activity, and 20 of 167 physically active patients played sport. CONCLUSIONS: In-line with the general population, we confirmed a high tendency toward a sedentary lifestyle (44% of respondents) among patients with organ transplants and those on waiting lists for organ transplants. Including a prescription for physical exercise as part of the therapeutic regimen can be useful for changing lifestyles during the pre- and post-transplantation period.

Promotion of Pre- and Post-Transplant Physical Exercise in the Emilia-Romagna Region: The Network of the Program "Transplantation, Physical Activity, and Sport".

BACKGROUND: Following the positive experience of the national project "A transplant...and now it's time for sport," the Transplant Reference Center of the Emilia-Romagna Region has pursued the promotion of pre- and post-transplant physical exercise by developing a network. METHODS: The path involved the transplant centers and operative units (UU.OO) who wanted to target transplant and waiting list patients, who are clinically stable, to perform personalized exercise through a program (supervised or not) prescribed by a specialist in sports medicine. With the collaboration of the Collective Prevention and Public Health Service, the network was established, consisting of the sports medicine centers and the gyms that promote health for adapted physical activity (PS-AMA). To implement the network, training courses for all the professionals involved (doctors, nurses, exercise specialists) and operational meetings in the transplant centers-nephrology units with patients' associations have been organized. RESULTS: To date, there are 14 transplant centers and UU.OO, 9 sports medicine centers, and 45 PS-AMA involved in this network. Seven training courses were organized with the participation of 193 health professionals. Since January 2016, there have been 65 transplanted patients and 5 patients on the waiting list who practice the prescribed exercise. Of these, 45 carry out supervised exercise in PS-AMA; 25 perform autonomous exercise. Each patient is monitored every 6 months. No problems related to the exercise performance were recorded. CONCLUSIONS: The development of a network of professionals and associations is the key element to raise awareness of physical activity among transplanted and waiting-for-transplant patients, reducing the pathologies associated with a sedentary lifestyle.

Detection of high levels of Survivin-immunoglobulin M immune complex in sera from hepatitis C virus infected patients with cirrhosis.

AIM: The identification and surveillance of patients with liver dysfunctions and the discovering of new disease biomarkers are needed in the clinical practice. The aim of this study was to investigate on Survivin-immunoglobulin (Ig)M immune complex (IC) as a potential biomarker of chronic liver diseases. METHODS: Serum levels of Survivin-IgM were measured using an enzyme-linked immunoassay that had been standardized and validated in our laboratory in 262 individuals, including healthy subjects and patients with chronic viral hepatitis, cirrhosis and hepatocellular carcinoma (HCC). RESULTS: Survivin-IgM IC was lower in healthy subjects (median, 99.39 AU/mL) than in patients with chronic viral hepatitis (median, 148.03 AU/mL; P = 0.002) or with cirrhosis (median, 371.00 AU/mL; P < 0.001). Among patients with cirrhosis, those with hepatitis C virus (HCV) infection showed the highest level of Survivin-IgM IC (median, 633.71 AU/mL; P < 0.001). The receiver-operator curve analysis revealed that Survivin-IgM accurately distinguishes HCV correlated cirrhosis from chronic viral hepatitis (area under the curve [AUC], 0.738; sensitivity, 74.5%; specificity, 70.7%). A multivariate logistic regression model, including Survivin-IgM IC, aspartate aminotransferase (AST) and AST/alanine aminotransferase (ALT) ratio increased the prediction accuracy for the identification of the cirrhotic HCV patients (AUC, 0.818; sensitivity, 87.2%; specificity, 65.9%). Conversely, Survivin-IgM IC significantly decreased in HCC patients (median, 165.72 AU/mL; P = 0.022). CONCLUSION: Our results suggest that Survivin-IgM immune complex may be used as a potential biomarker for liver damage, particularly for the identification of the HCV-related cirrhotic population.

Should we routinely measure portal pressure in patients with cirrhosis, using hepatic venous pressure gradient (HVPG) as a guide for prophylaxis and therapy of bleeding and rebleeding? No.

Portal hypertension (PH) is a severe complication of liver cirrhosis. Measurement of the degree of portal hypertension is usually performed by measuring the hepatic venous pressure gradient (HVPG) which is the difference between the free hepatic venous pressure (FHVP) and the wedged hepatic venous pressure (WHPG). The HVPG accurately reflects the degree of PH in the majority of liver diseases. PH is defined by an increase of HVPG values above the normal upper limit of 5 mm Hg, while clinically significant PH is defined by an HVPG to ≥10 mm Hg. Although measurement of HVPG potentially has several applications, in clinical practice its major use has been related to the assessment of hemodynamic response to pharmacological therapy, in order to evaluate the efficacy of treatment and to predict the risk of rebleeding from esophageal varices. When properly performed, HVPG is a reliable, safe and good predictive tool in the management of portal hypertension. However, the need for appropriate equipment, sufficient and reliable operators and costs, have discouraged its use outside Liver Units specifically devoted to the clinical management of portal hypertension. This has diminished its applicability. Combining its use with transjugular liver biopsy and using the prognostic value of HVPG may help encourage its use.

Plasma cytokines and portopulmonary hypertension in patients with cirrhosis waiting for orthotopic liver transplantation.

Portopulmonary hypertension (PPHTN) is a rare complication in patients with portal hypertension. A role of endothelin 1 (ET-1) and other cytokines was demonstrated in primary pulmonary hypertension but not in PPHTN. We evaluated the possible role of ET-1, interleukin 6 (IL-6), interleukin 1ß (IL-1ß), and tumor necrosis factor alpha (TNF-α) in the pathogenesis of PPHTN. Plasmatic concentrations of ET-1, IL-6, IL-1ß, and TNF-α were measured in patients with pulmonary systolic arterial pressure (PAPs) >30 mm Hg and in patients with cirrhosis. In all, Six out of 11 patients with PAPs >30 mm Hg had PPHTN on right heart catheterization. The remaining 10 patients had an hyperdynamic circulation (HC). In PPHTN patients, ET-1 and IL-6 were significantly higher compared with HC and patients with cirrhosis. Endothelin 1 and IL-6 could be implicated in the pathogenesis of PPHTN. On the basis of these results, ET-1 receptor antagonists or anti-IL-6 could have a rationale in the treatment of PPHTN.

HCV carriers with normal alanine aminotransferase levels: healthy persons or severely ill patients? Dealing with an everyday clinical problem.

Approximately 30% of patients with chronic HCV infection show persistently normal ALT levels. Although formerly referred to as 'healthy' or 'asymptomatic' HCV carriers, and thus historically excluded from antiviral treatment, it has now become clear that the majority of these patients have some degree of histological liver damage that may be significant in up to 20% of patients and might progress toward a more severe degree of liver fibrosis. A significant proportion of patients (> or =20%) experience periods of increased serum ALT (flare) associated with enhanced disease progression. However, controversies still exist in clinical practice regarding the definition of 'persistent' ALT normality, the virological and histological features of these subjects, the need for liver biopsy, the role of non invasive tools for the assessment of liver fibrosis (transient hepatic elastography, fibroscan), and the natural history and optimal management of chronic hepatitis C with normal ALT. The advent of new therapeutic options (pegylated interferons plus ribavirin) has shifted treatment targets toward eradication of underlying infection, with therapy decision based on age, severity of disease and likelihood of response rather than on aminotransferase levels. This review does approach the main unresolved issues on this topic in the form of a dialog between a hepatologist and a patient with HCV infection but normal alanine aminotransferase levels, trying to give evidence-based answers to the more frequently asked questions from patients and their physicians.

Quantitation of tissue polypeptide antigen (TPA) in hepatic and systemic circulation in patients with chronic liver diseases.

BACKGROUND AND AIM: Abnormal serum tissue polypeptide antigen (TPA) values are commonly found in patients with chronic liver damage and liver cirrhosis even in the absence of malignancies. The aim of this study was to compare serum TPA levels in patients with cirrhosis, to examine correlations between TPA levels and the degree of portal hypertension, and to evaluate TPA concentrations in paired hepatic and peripheral blood samples. METHODS: A total of 128 patients with chronic liver disease of various severity were studied prospectively. TPA concentrations in hepatic vein and peripheral blood were determined, and Hepatic Vein Pressure Gradient (HVPG) was measured. RESULTS: TPA levels were significantly higher in patients with cirrhosis than in those with chronic hepatitis, and in systemic circulation than in hepatic vein blood. Peripheral but not hepatic TPA levels did correlate with the HVPG. Subjects with clinically significant portal hypertension (HVPG > 10 mmHg) showed significantly higher peripheral TPA levels than those with HVPG < 10 mmHg. CONCLUSIONS: Our data suggest that the increased TPA levels observed in cirrhotic patients and the high systemic-to-hepatic blood TPA gradient are probably due to the presence of portal-systemic shunts rather than to hepatic necro-inflammatory activity. In clinical practice, TPA determination could help us to identify and to follow up cirrhotic patients with more severe portal hypertension.

Treatment of hepatitis C virus carriers with persistently normal alanine aminotransferase levels with peginterferon alpha-2a and ribavirin: a multicentric study.

BACKGROUND/AIMS: To evaluate, in clinical practice, the efficacy and safety of combined antiviral treatment in hepatitis C virus (HCV) carriers with normal alanine aminotransferase (ALT) levels. METHODS: Eighty-eight HCV carriers with persistently normal ALT levels were enrolled. All patients received peginterferon (PEG-IFN) alpha-2a 180 microg once weekly plus ribavirin (RBV) 800 mg/day for 24 weeks (HCV-2 and -3) or 1000-1200 mg/day for 48 weeks (HCV-1). RESULTS: Rapid virological response (RVR) was seen in 66/88 patients (75%): 19/32 HCV-1 (59%), 40/46 HCV-2 (87%) and 7/10 HCV-3 patients. Younger patients, leaner subjects and patients with non-1 genotype or lower baseline HCV RNA levels were more likely to achieve an RVR. Sustained virological response (SVR) was seen in 69/88 patients (78%): 20/32 HCV-1 patients (62%), 41/46 HCV-2 patients (89%) and 8/10 (80%) HCV-3 patients. The overall SVR rate was 88% in patients with RVR (58/66) and 50% in those without RVR. CONCLUSIONS: The combination of PEG-IFN alpha-2a and RBV produces, in patients with normal ALT, virological response rates that are comparable or even higher than those obtained in patients with elevated ALT levels. Thus, we suggest that in selected cases immediate therapy might be preferred to a 'wait-and-see' policy.

Antiviral treatment of HCV carriers with persistently normal ALT levels.

Approximately 30% of patients with chronic HCV infection show persistently normal alanine aminotransferase levels (PNAL). The prevalence of HCV carriers with normal liver seems to be very low (less than 15-20%). Liver disease is usually minimal/mild and fibrosis is generally absent or minimal, although the association of normal alanine aminotransferase (ALT) with cirrhosis or with liver cancer has been reported. In all studies, liver histology was, on average, significantly less severe in subjects with PNAL than with abnormal ALT. Although the majority of data seem to show that HCV carriers with normal ALT have mild and stable disease, with a favourable prognosis, several studies reported a significant progression of fibrosis in approximately 20-30% of the patients with ALT normality, and the development of HCC in some cases has been described, despite persistent ALT normality. Sudden worsening of disease with ALT increase and histological deterioration has been described after up to 15 years of follow-up, in particular in patients harboring genotype 2. As to antiviral treatment, it has been clearly stated that it no longer seems reasonable to affirm that sustained response rates for patients with normal ALT levels are any different than those for patients with elevated ALT levels when the combination of pegylated interferon (IFN) and ribavirin is used. The issue at hand is whether or not patients with mild disease should be treated. There are numerous other factors which impact on this decision, including genotype, histology, patients motivation, symptoms, co-morbid illness, and the age of the patient.

Hepatic venous pressure gradient does not correlate with the presence and the severity of portal hypertensive gastropathy in patients with liver cirrhosis.

BACKGROUND AND AIMS: To evaluate whether the hepatic venous pressure gradient (HVPG) differs between cirrhotic patients with severe portal hypertensive gastropathy (PHG) and those with mild or absent PHG. METHODS: 59 cirrhotic patients with portal hypertension underwent hepatic vein catheterisation. 44 patients (76%) had PHG (16 mild and 28 severe). SETTING: tertiary care setting (Liver Unit, Internal Medicine). RESULTS: HVPG values did not differ between the patients without PHG (21.6 +/- 10.1 mmHg) and those with PHG (18.6 +/- 9.1 mmHg), nor between those with mild (19.3 +/- 4.3 mmHg) or severe PHG (17.7 +/- 4.6 mmHg; p = 0.26). The overall prevalence of PHG and the proportion of patients with severe PHG did not differ regarding the Child Pugh classification. The etiology of the cirrhosis did not influence the HVPG. No correlations were found between HVPG values and Child Pugh score, age, platelet count, prothrombin time, bilirubin levels and ALT values. The HVPG did not differ between patients with small, medium or large esophageal varices, nor between subjects with or without gastric varices. CONCLUSIONS: Our data show that PHG does not correlate with the degree of portal pressure, and that the prevalence and the severity of this condition are not influenced by the severity of underlying liver disease or by the size of varices.

Nerve growth factor involvement in liver cirrhosis and hepatocellular carcinoma.

AIM: To define NGF (nerve growth factor) and its high-affinity receptor trkA(NGF) presence and distribution in fibrotic liver and in HCC, and to verify if NGF might have a role in fibrosis and HCC. METHODS: Intracellular distribution of NGF and trkA(NGF) were assessed by immunohistochemistry and immuno-electron microscopy in liver specimens from HCC, cirrhosis or both. ELISA was used to measure circulating NGF levels. RESULTS: NGF and trkA(NGF) were highly expressed in HCC tissue, mainly localized in hepatocytes, endothelial and some Kupffer cells. In the cirrhotic part of the liver they were also markedly expressed in bile ducts epithelial and spindle-shaped cells. Surprisingly, in cirrhotic tissue from patients without HCC, both NGF and trkA(NGF) were negative. NGF serum levels in cirrhotic and/or HCC patient were up to 25-fold higher than in controls. CONCLUSION: NGF was only detected in liver tissue with HCC present. Intracellular distribution suggests paracrine and autocrine mechanisms of action. Better definition of mechanisms may allow for therapeutic and diagnostic/prognostic use of NGF.