Ernesto Paoletti

Prolonged therapy with ACE inhibitors induces a regression of left ventricular hypertrophy of dialyzed uremic patients independently from hypotensive effects

Left ventricular hypertrophy (LVH), which frequently occurs in chronic uremia, may be due in part to factors other than arterial hypertension, chronic anemia, and/or other well-known loading conditions inherent to the uremic state. Angiotensin-converting enzyme (ACE) inhibitors may be able to reverse LVH by mechanisms independent of their antihypertensive effects. In this study, 18 subjects free of arterial hypertension or severe anemia were selected from 170 chronically hemodialyzed uremic patients after fulfilling the criterion of a supranormal left ventricular mass (LVM). Ten subjects agreed to undergo treatment with 2.5 to 20 mg lisinopril every other day over a period of 2 years, during which annual determinations of the LVM by echocardiography and of the 24-hour blood pressure with a portable device were carried out. Eight patients unwilling to undergo the treatment served as controls. The average resting left ventricular mass index (LVMi) of the overall group was 178 +/- 30 g/m2 body surface area (+/- SD), and did not differ between the two subgroups. Lisinopril treatment significantly decreased the LVM of eight of 10 treated subjects and actually even completely normalized it in three. The LVM of the untreated group remained unchanged. Systolic and diastolic blood pressures were 138 +/- 5 mm Hg and 78 +/- 6 mm Hg in the treated group and 133 +/- 9 mm Hg and 75 +/- 4 mm Hg in the untreated group, respectively (P = NS), and did not vary over the following 2 years. This study indicates that a mild degree of LVH, which is seemingly independent of arterial blood pressure load, does exist in a tight subset of uremic patients. This study also demonstrates that this type of LVH is apparently nonprogressive. ACE inhibitors given at doses not affecting blood pressure are able to reverse it.

Renal anaemia and EPO hyporesponsiveness associated with vitamin D deficiency: the potential role of inflammation

Resistance to erythropoiesis-stimulating agents (ESAs) has been observed in a considerable proportion of patients with chronic kidney disease (CKD) and it is reportedly associated with adverse outcomes, such as increased cardiovascular morbidity, faster progression to end-stage renal disease (ESRD) and all-cause mortality. The major causes of ESA resistance include chronic inflammation producing suppressive cytokines of early erythroid progenitor proliferation. In addition, pro-inflammatory cytokines stimulate hepcidin synthesis thus reducing iron availability for late erythropoiesis. Recent studies showing an association in deficiencies of the vitamin D axis with low haemoglobin (Hb) levels and ESA resistance suggest a new pathophysiological co-factor of renal anaemia. The administration of either native or active vitamin D has been associated with an improvement of anaemia and reduction in ESA requirements. Notably, these effects are not related to parathyroid hormone (PTH) values and seem to be independent on PTH suppression. Another possible explanation may be that calcitriol directly stimulates erythroid progenitors; however, this proliferative effect by extra-renal activation of 1α-hydroxylase enzyme is only a hypothesis. The majority of studies concerning vitamin D deficiency or supplementation, and degree of renal anaemia, point out the prevalent role of inflammation in the mechanism underlying these associations. Immune cells express the vitamin D receptor (VDR) which in turn is involved in the modulation of innate and adaptive immunity. VDR activation inhibits the expression of inflammatory cytokines in stromal and accessory cells and up-regulates the lymphocytic release of interleukin-10 (IL-10) exerting both anti-inflammatory activity and proliferative effects on erythroid progenitors. In CKD patients, vitamin D deficiency may stimulate immune cells within the bone marrow micro-environment to produce cytokines, inducing impaired erythropoiesis. Immune activation involves the reticuloendothelial system, increasing hepcidin synthesis and functional iron deficiency. Consequences of this inflammatory cascade are erythropoietin (EPO) resistance and anaemia. Given the key role of inflammation in the response to EPO, the therapeutic use of agents with anti-cytokines properties, such as vitamin D and paricalcitol, may provide benefit in the prevention/treatment of ESA hyporesponsiveness.

Effect of Sirolimus on Left Ventricular Hypertrophy in Kidney Transplant Recipients: A 1-Year Nonrandomized Controlled Trial

BACKGROUND Left ventricular hypertrophy (LVH) after renal transplantation may be affected by immunosuppressive therapy. STUDY DESIGN Nonrandomized controlled trial evaluating the effect of sirolimus (SRL) on LVH of renal transplant recipients (RTRs). SETTING & PARTICIPANTS 13 RTRs without diabetes who had received a single-kidney transplant from a deceased donor with chronic allograft dysfunction and biopsy-proven allograft nephropathy who were converted from calcineurin-inhibitor (CNI) to SRL treatment; 26 controls matched for age and year of transplantation who were not converted from CNI to SRL treatment. INTERVENTION Conversion from CNI to SRL therapy. OUTCOMES & MEASUREMENTS Left ventricular mass determination by using echocardiography at baseline and again 1 year later. Blood pressure (BP), hemoglobin level, serum creatinine level, uric acid level, lipid levels, trough levels of immunosuppressive drugs, and daily proteinuria were assessed at least twice monthly. Conventional antihypertensive therapy was used to achieve BP of 130/80 mm Hg or less. RESULTS The study population included 26 men and 13 women (age, 25 to 66 years). Changes in BP were similar in the 2 groups (between-group difference, -4 +/- 5 mm Hg; P = 0.5 for systolic BP; -2 +/- 3; P = 0.6 for diastolic BP), whereas left ventricular mass significantly decreased in the SRL group alone (between-group difference, 8.6 +/- 2.4 g/m(2.7); P < 0.001) because of a decrease in both the interventricular septum and left ventricular posterior wall. LVH regressed in 12 of 13 patients on SRL therapy and 10 of 26 controls (P = 0.002). LIMITATIONS Nonrandomized design. Single-center study with small sample size. CONCLUSIONS Conversion from CNI to SRL therapy may regress LVH in RTRs regardless of BP changes, mainly by decreasing left ventricular wall thickness, thus suggesting nonhemodynamic-effect mechanisms of SRL on left ventricular mass.

Association of Arterial Hypertension With Renal Target Organ Damage in Kidney Transplant Recipients: The Predictive Role of Ambulatory Blood Pressure Monitoring

Background. Although arterial hypertension is a powerful predictor of graft failure, only few studies have evaluated 24-hr blood pressure (BP) profile in renal transplant recipients (RTRs). Methods. We performed ambulatory blood pressure monitoring (ABPM) in 94 RTRs (65 men; age 28-71 years) with 1-year functioning grafts. Serum biochemical parameters, daily proteinuria, and transplantation-related data were evaluated in all subjects. Results. ABPM showed that only 5% of RTRs were normotensives (BP<130/80 mm Hg) and identified 29% of patients with nocturnal hypertension. A strong, direct correlation was shown between each set of both systolic BP and diastolic BP measured by ABPM and serum creatinine, daily proteinuria, and serum triglycerides (P at least <0.025 for each). Serum creatinine immediately after transplantation and 1-yr asleep diastolic BP were the only significant predictors of 1-yr creatinine (P<0.0001; r2=0.49), whereas awake systolic BP was the only predictor of daily proteinuria (r2=0.39; P=0.005) by multiple regression analysis. Conclusions. BP assessed by ABPM proved to be a stronger predictor of renal graft damage than traditional immunologic factors. ABPM improved the diagnostic accuracy of arterial hypertension in RTRs and was the only effective tool in disclosing the association of BP with 1-year renal transplant outcome.

Effect of everolimus on left ventricular hypertrophy of de novo kidney transplant recipients: a 1 year, randomized, controlled trial.

Background. Although conversion from calcineurin inhibitors to mammalian target of rapamycin inhibitors proved to be effective in regressing left ventricular hypertrophy (LVH) in renal transplant recipients (RTRs) with chronic allograft dysfunction, there are currently no reports of randomized trials on this issue involving de novo RTRs administered everolimus (EVL). Methods. This randomized, open-label, controlled trial evaluated the effect of EVL on the left ventricular mass index (LVMi) of 30 nondiabetic RTRs (21 men; age 28–65 years). Ten were allocated to EVL plus reduced-exposure cyclosporine A (CsA), and 20 to standard dose CsA. LVMi was assessed by echocardiography both at baseline and 1 year later. Blood pressure (BP), hemoglobin, serum creatinine, lipids, trough levels of immunosuppressive drugs, and daily proteinuria were also evaluated twice monthly. Antihypertensive therapy that did not include renin-angiotensin system blockers was administered to achieve BP less than or equal to 130/80 mm Hg. Results. Changes in BP were similar in the two groups (between group difference 1.2±5.7 mm Hg, P=0.84 for systolic, and −1.5±3.7, P=0.69, for diastolic BP), whereas LVMi significantly decreased in the EVL group alone (between group difference 9.2±3.1 g/m2.7, P=0.005), due to a reduction in both the interventricular septum and the left ventricular posterior wall thickness. EVL therapy together with baseline LVMi were the only significant predictors of LVH regression according to a multivariate model that explained 49% of the total LVMi variance (P=0.0015). Conclusions. An immunosuppressive regimen consisting of EVL plus reduced exposure CsA proved to be effective in regressing LVH in RTRs regardless of BP, mainly by reducing left ventricular wall thickness.

Is left ventricular hypertrophy a powerful predictor of progression to dialysis in chronic kidney disease

BACKGROUND The role of cardiovascular factors in predicting renal outcome has not been extensively elucidated. Herein, we report a prospective evaluation of the impact of left ventricular hypertrophy (LVH) on outcome in non-diabetic patients with chronic kidney disease (CKD). METHODS We studied 144 patients (99 men; age 62±14 years) with stage 3-4 CKD, with baseline assessment of left ventricular mass index (LVMi) by echocardiography, estimated glomerular filtration rate (eGFR) by MDRD equation, 24-h blood pressure profile and 24-h proteinuria. Combined end point was progression to ESRD requiring dialysis, or death within 5 years. RESULTS Forty-nine patients (34%) progressed to dialysis, 24 (17%) died, 57 (39%) were dialysis-free after 5 years and 14 were lost to follow-up. Multivariate Cox proportional hazards analysis showed that increased LVMi (HR 1.28, 95% CI 1.17-1.40 for each 10-g/m2 increase, P<0.0001) and reduced eGFR (5% risk increase for each 1-mL/min reduction, P=0.027) were the significant predictors of the combined end point in stage 3 CKD patients, whereas LVMi proved to be the only significant predictor of the combined end point in patients with stage 4 CKD (HR 1.19, 95% CI 1.09-1.31, P<0.0001). The same analysis showed that LVMi was the only significant predictor of progression to dialysis in stage 3 CKD patients (HR 1.42, 95% CI 1.23-1.64 for each 10-g/m2 increase, P<0.0001), while a 20% increase in the risk of progression to ESRD was observed for each 10-g/m2 increase in LVMi (P<0.0001), and a 10% increase for each 1-mL/min reduction in eGFR (P=0.046) in patients with stage 4 CKD. When evaluating the predictive role of LVMi on outcome using AUC-ROC curves, the overall performance of the model including LVMi (AUC 0.877, 95% CI 0.8-0.954) was superior to the model including eGFR (AUC 0.737, 95% CI 0.656-0.817) for the end point of progression to dialysis (P=0.026, Hanley test). CONCLUSIONS LVH proved to be the strongest predictor of the risk of progression to dialysis in non-diabetic CKD, especially among patients with less advanced renal dysfunction. Regardless of whether it is a simple marker or a pathogenetic factor, LVH encompasses all factors possibly affecting renal and general outcome in CKD patients.

Effects of a Protein Meal on Blood Amino Acid Profile in Patients with Chronic Renal Failure

Arterial whole blood levels of amino acids were determined in patients with chronic renal failure and in healthy subjects before and after 270 min after the ingestion of a grilled beefsteak (4 g/kg). In patients, total nonessential amino acids increased significantly more (+46%) than in controls owing to an exaggerated rise of serine, glutamine, proline, glycine, cyst(e)ine and alanine. Total essential amino acids increased as much as in controls; however, threonine, histidine and phenylalanine showed greater increases, while tryptophan had a smaller increment. Abnormalities in amino acid levels were even more evident in the postprandial period than in the postabsorptive state owing to reduced levels of valine, leucine, tryptophan, tyrosine, aspartate and glutamate and higher levels of glutamine, proline, glycine, cyst(e)ine, threonine, histidine and phenylalanine. Moreover, after the meal, the ratios total essential amino acids/total nonessential amino acids, valine/glycine, and branched-chain amino acids/total amino acids rose but persisted to be reduced whereas tryptophan/total amino acids and tyrosine/phenylalanine ratios increased in controls, but did not change in patients. In conclusion, in chronic renal failure, protein ingestion enhances the imbalance in amino acid levels already present in the postabsorptive state. The all data indicate that in patients with chronic renal failure, the metabolism of exogenous protein is impaired and the flow of amino acids to the organs is altered during the phase of body nitrogen replenishment.

Effects of ACE inhibitors on long-term outcome of renal transplant recipients: a randomized controlled trial.

Background Available data on the role of renin-angiotensin system blockade in renal transplantation are inconclusive. Herein, we report the long-term results of a randomized controlled trial planned to evaluate the impact of angiotensin-converting enzyme inhibitors (ACE-i) on the cardiovascular outcome of renal transplant recipients (RTRs) receiving calcineurin inhibitors, steroids, and mycophenolate mofetil. Methods Thirty-six RTRs were allocated to receive ACE-i and 34 served as controls. Survival free of a composite endpoint consisting of death, major cardiovascular events, renal graft loss or creatinine doubling, and survival free of each single endpoint were analyzed in both groups according to a modified intention-to-treat analysis. Results During a 10-year follow-up, three patients died (one in the ACE-i group and two controls) and three lost their graft (two receiving ACE-i and one control). Three major cardiovascular events were observed in the ACE-i group and 12 among controls (P=0.008). At the end of observation, a significant increase in urinary protein excretion rate was only observed in controls (P=0.017). Compared with controls, RTRs administered ACE-i had significantly better survival free of the combined endpoint (P=0.0102, log-rank test) and free of major cardiovascular events (P=0.0027) without significant differences in renal outcome. By Cox regression analysis, ACE-i therapy resulted in the most powerful predictor of survival free of composite endpoint (hazard ratio, 0.165; 95% confidence interval, 0.053–0.512; P=0.0018) and survival free of major cardiovascular events (hazard ratio, 0.209; 95% confidence interval, 0.068–0.636; P=0.0059). Conclusions Prolonged therapy with ACE-i was associated with better general and cardiovascular outcome of RTRs without detrimental effects on renal graft function.

Update on erythropoietin treatment : Should hemoglobin be normalized in patients with chronic kidney disease?

The partial correction of ESRD anemia by recombinant human erythropoietin (EPO) has resulted both in generalized improvement in quality of life and physical activity and in reduced mortality and hospitalization rate. The question remains as to whether normalizing hemoglobin (Hgb) is desirable in patients with chronic kidney disease (CKD). This review provides an analysis and commentary on the available reports and, for the most part, randomized, controlled trials on the topic. In dialysis patients, normalization of Hgb is associated with improved quality of life and exercise capacity but not with reduced mortality and hospitalization rate. Moreover, no significant changes in the degree of left ventricular hypertrophy have been demonstrated. By contrast, an increased mortality rate has been reported for hemodialysis patients with overt cardiovascular disease (CVD) when randomly assigned to normal hematocrit by EPO. Data regarding patients who have CKD but are not yet on renal replacement therapy are scarce, and the effects of EPO on renal disease progression require further elucidation through controlled trials. The conclusion that can be drawn from the available studies is that Hgb >11 g/dl is the minimum required to achieve improved quality of life in patients with CKD, whereas values >12 g/dl are not recommended for patients with overt CVD. Finally, Hgb normalization might reasonably be restricted to a selected population of younger, employed, and active individuals, provided that they do not have CVD.

Associations of Left Ventricular Hypertrophy and Geometry with Adverse Outcomes in Patients with CKD and Hypertension

BACKGROUND AND OBJECTIVES Left ventricular hypertrophy (LVH) and abnormal left ventricular (LV) geometry predict adverse outcomes in the general and hypertensive populations, but findings in CKD are still inconclusive. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We enrolled 445 patients with hypertension and CKD stages 2-5 in two academic nephrology clinics in 1999-2003 who underwent both echocardiography and ambulatory BP monitoring. LVH (LV mass >100 g/m(2) [women] and >131 g/m(2) [men]) and relative wall thickness (RWT) were used to define LV geometry: no LVH and RWT≤0.45 (normal), no LVH and RWT>0.45 (remodeling), LVH and RWT≤0.45 (eccentric), and LVH and RWT>0.45 (concentric). We evaluated the prognostic role of LVH and LV geometry on cardiovascular (CV; composite of fatal and nonfatal events) and renal outcomes (composite of ESRD and all-cause death). RESULTS Age was 64.1±13.8 years old; 19% had diabetes, and 22% had CV disease. eGFR was 39.9±20.2 ml/min per 1.73 m(2). LVH was detected in 249 patients (56.0%); of these, 125 had concentric LVH, and 124 had eccentric pattern, whereas 71 patients had concentric remodeling. Age, women, anemia, and nocturnal hypertension were independently associated with both concentric and eccentric LVH, whereas diabetes and history of CV disease associated with eccentric LVH only, and CKD stages 4 and 5 associated with concentric LVH only. During follow-up (median, 5.9 years; range, 0.04-15.3), 188 renal deaths (112 ESRD) and 103 CV events (61 fatal) occurred. Using multivariable Cox analysis, concentric and eccentric LVH was associated with higher risk of CV outcomes (hazard ratio [HR], 2.59; 95% confidence interval [95% CI], 1.39 to 4.84 and HR, 2.79; 95% CI, 1.47 to 5.26, respectively). Similarly, greater risk of renal end point was detected in concentric (HR, 2.33; 95% CI, 1.44 to 3.80) and eccentric (HR, 2.30; 95% CI, 1.42 to 3.74) LVH. Sensitivity analysis using LVH and RWT separately showed that LVH but not RWT was associated with higher cardiorenal risk. CONCLUSIONS In patients with CKD, LVH is a strong predictor of the risk of poor CV and renal outcomes independent from LV geometry.