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Roberto Marcén

Publications and source records attributed to Roberto Marcén.

11 recordsLinked to original sources

Lumbar bone mineral density in renal transplant patients on neoral and tacrolimus: a four-year prospective study.

BACKGROUND: This prospective study was designed to investigate the long-term evolution of bone mineral density (BMD) in kidney transplant recipients. METHODS: In 86 patients with functioning grafts, 65 on tacrolimus-based immunosuppression and 21 on cyclosporine-based immunosuppression, laboratory parameters and BMD measurements in lumbar spine (L2-L4) and femoral neck (FN) were performed by DEXA in the first month after transplantation (baseline) and yearly thereafter up to the fourth year. RESULTS: BMD did not change at 12 months in lumbar spine nor in the FN. Detailed analysis identified three patterns of BMD in lumbar spine at 12 months: BMD remained stable in 27 patients (31.4%), decreased >2% in 31 (36.0%) and increased >2% in 28 (32.6%). Patients with no change or gain presented a parallel increase of BMD in FN (P<0.001 in both groups). On multivariate analysis, the variables associated with no change or lumbar BMD loss were total prednisone dose in grams at 12 months (OR 1.402; 95% CI 1.038-1.893; P=0.028), calcitriol levels at 12 months (OR 0.936; 95% CI 0.892-0.982; P=0.007) and lumbar BMD at baseline (OR 1.006; 95% CI 1.002-1.010; P=0.002). Late treatment with calcium supplements and calcitriol did not improve osteopenia. CONCLUSIONS: One third of patients had bone loss mainly during the first year of follow-up. Bone loss was associated to higher baseline BMD, high steroid dose, and lower calcitriol levels at 1 year. Late administration of calcitriol and calcium supplements did not improve posttransplant osteopenia. More than 50% of patients were osteopenic 4 years after transplantation.

Adult↗

Cardiovascular risk factors in renal transplantation--current controversies.

Cardiovascular diseases are more common in renal transplant recipients than in the general population, and a number of 'traditional' risk factors, such as smoking, diabetes mellitus and dyslipidaemia, are known to be associated with an increased risk. However, concentrating solely on these risk factors can lead to an underestimation of the true risk in this patient population, because other factors such as C-reactive protein and homocysteine levels are also associated with cardiovascular morbidity and mortality. Renal insufficiency also appears to be a key cardiovascular risk factor in the general population, with increasing proteinuria and decreasing glomerular filtration rate related to increased risk. In renal transplant recipients, a high proportion of whom have some renal insufficiency, the role of graft dysfunction in cardiovascular risk is controversial. While some studies have shown no correlation between graft dysfunction and congestive heart failure or ischaemic heart disease, registry data suggest that increased post-transplant serum creatinine levels are strongly associated with cardiovascular risk. This is believed to be the result of cardiovascular disease developing in the pre-transplantation period, as renal transplantation has been shown significantly to improve cardiovascular risk. As such, renal transplant recipients should be routinely screened for cardiovascular disease pre-transplantation, and immunosuppressive therapy should be tailored to minimize further risk. Different immunosuppressive agents, such as corticosteroids and calcineurin inhibitors, are associated with different exposure to cardiovascular risk, and studies involving withdrawal of these agents have generally shown improvement in parameters such as blood pressure and dyslipidaemia. However, these benefits are often associated with an increased incidence of acute rejection, although overall graft loss and mortality rates are not affected. Further studies are required to determine optimal regimens for minimizing cardiovascular risk in renal transplant recipients.

Adult↗

Conversion to everolimus in a patient with arterial hypertension and recurrent cutaneous neoplasia--a case report.

Calcineurin inhibitors (CNIs) are frequently associated with side effects such as nephrotoxicity and hypertension, so CNI withdrawal from immunosuppressive regimens is desirable in certain cases. The proliferation signal inhibitors/mammalian target of rapamycin inhibitors everolimus and sirolimus may play an important role in achieving CNI withdrawal. Studies on sirolimus have shown that conversion from CNIs is associated with improvements in renal function and hypertension. A case report is presented of a renal transplant recipient who experienced hypertension and recurrent cutaneous neoplasia while receiving a ciclosporin (CsA)-based immunosuppressive regimen. After transplantation, the patient received full-dose CsA and prednisolone. After 7 years, the patient's serum creatinine increased from 1.9 mg/dl to 2.5 mg/dl, and mycophenolate mofetil (MMF, 1000 mg/day) was introduced, enabling the CsA dose to be reduced to 100 mg b.i.d. The patient also required resection of five cutaneous neoplastic lesions; this led to the decision to stop CsA and start treatment with everolimus 1.5 mg/day, which was increased to 3.0 mg/day to achieve target trough blood levels of 3 ng/ml. To avoid over-immunosuppression, the MMF dose was reduced to 500 mg/day. After conversion, the patient experienced a substantial improvement in blood pressure, from 175/85 mmHg to 155/70 mmHg. Serum creatinine levels decreased to 1.6 mg/dl, and there has been no recurrence of cutaneous neoplasia in 9 months of follow-up. Therefore, conversion to everolimus from CsA in a renal transplant recipient led to improvements in blood pressure and resolution of recurrent cutaneous neoplasia, with no evidence of rejection or changes in renal function.

Blood Pressure↗

Ischemic heart disease after renal transplantation in patients on cyclosporine in Spain.

Ischemic heart disease (IHD), more common among transplant recipients than in the general population, accounts for approximately 50% of cardiovascular deaths. Despite its importance, only a few publications have addressed the prevalence of and risk factors for this complication. This was a retrospective cohort study in 2382 cadaver renal transplant recipients who were treated with cyclosporine as initial immunosuppression. Two groups were formed. The first group consisted of 163 patients with IHD, and the second group consisted of 326 patients without IHD. The prevalence of IHD was 6.8%, and the incidence was 15.7/1000 patient-years. Cardiac events presented during the first year in 62 (38%) patients. Multivariate analysis showed that the risk factors for IHD were age at transplant in years (relative risk [RR] 1.054; 95% confidence interval [CI] 1.033 to 1.075; P = 0.000), male gender (RR 1.940; 95% CI 1.221 to 3.081; P = 0.005), body weight at transplant in kg (RR 1.020; 95% CI 1.007 to 1.033; P = 0.002), pretransplantation cardiovascular disease (RR 2.150; 95% CI 1.733 to 3.359; P = 0.001), and a history of pretransplantation hypercholesterolemia (RR 2.032; 95% CI 1.378 to 2.998; P = 0.000). When only ischemic events that occurred 12 mo after transplantation were taken into consideration, the risk factors were age, male gender, body weight, smoking, and pretransplantation and posttransplantation hypercholesterolemia, whereas pretransplantation cardiovascular disease disappeared from the model. IHD affected nearly 7% of transplant recipients. Smoking, hypertension, and hypercholesterolemia constituted the treatable risk factors for IHD in this population. Emphasis should be placed on the need to stop smoking and to control hypertension and pre- and posttransplantation levels of serum cholesterol.

Adult↗

Clinical experience with everolimus (Certican) in elderly recipients: the "old-for-old" concept.

BACKGROUND: With an increasing number of elderly patients now waiting for a kidney transplant, and the percentage of kidney donors over 55 years also rising, harvesting older kidneys specifically for use in older recipients is a way of extending the donor pool for renal transplantation. METHODS: Two case studies from an everolimus (Certican) Phase III trial (A2306) are presented. They illustrate clinical experience of achieving stable graft function in the "old-for-old" kidney transplant program at the Ramon y Cajal Hospital in Madrid, Spain. RESULTS: The first case study demonstrates that stable graft function can be achieved in an "old-for-old" kidney transplant patient, who receives everolimus in combination with reduced-exposure cyclosporine (CsA). To optimize graft function in the long-term, CsA C(2) blood levels should be <400 ng/ml. The second case study highlights how "old-for-old" renal transplant recipients can be at risk of calcineurin-inhibitor (CNI)-induced nephrotoxicity. Here, graft function did not improve following CsA dose reduction; thus, CsA was withdrawn 1 year posttransplant. Stable graft function that is acceptable for an "old-for-old" kidney transplant was then achieved with everolimus trough blood levels of 10-15 ng/ml and low-dose prednisone. CONCLUSIONS: In these cases, everolimus was used safely and effectively in the "old-for-old" kidney transplant setting. Its combination with reduced-exposure CsA, or its facilitation of CsA withdrawal, minimized the risk of nephrotoxicity in the older renal graft. These findings need to be confirmed in larger studies specific to this population.

Age Factors↗

Clinical experience with everolimus (Certican): optimizing dose and tolerability.

BACKGROUND: Everolimus (Certican), a novel proliferation signal inhibitor, allows calcineurin inhibitor dose reduction in transplant patients, minimizing risk of nephrotoxicity without loss of immunosuppressive efficacy. As a result of its mode of action, this class of agent (i.e., everolimus and sirolimus) is associated with certain adverse events (e.g., lymphocele, arthralgia, edema and hyperlipidemia). METHODS: Three case studies from within an everolimus Phase III trial (A2306) are presented with the aim of illustrating how treatment-related adverse events can be managed. RESULTS: The combination of everolimus with reduced-exposure cyclosporine was efficacious in these patients. One experienced mild acute rejection that was managed with steroid boluses. All have acceptable graft function during follow-up to date. Moderate lymphocele either resolved spontaneously or was easily managed by povidine-iodine instillations. One patient developed serious early lymphocele that, unusually, required surgical intervention. Everolimus dose reduction or withdrawal was not necessary to effectively manage lymphocele of any severity. A case of bilateral multiple arthralgia was effectively managed with everolimus dose reduction, but still maintained everolimus trough blood levels at approximately 3 ng/ml. Eyelid and ankle edemas were also easily managed with low dose furosemide, preferably coupled with cyclosporine and everolimus dose reduction. Hyperlipidemia responded to statin therapy. CONCLUSIONS: Everolimus-related adverse events can be effectively managed either with other treatments or, where necessary, by everolimus dose reduction, without loss of efficacy. Discontinuing everolimus therapy is generally not necessary.

Adult↗

Clinical outcomes and C2 cyclosporin monitoring in maintenance renal transplant recipients: 1 year follow-up study.

BACKGROUND: Cyclosporin A (CsA) concentration monitoring with 2 h post-dosing levels (C2) correlates with the incidence of rejection and graft outcome in de novo renal transplant patients. The advantages of this policy beyond the first 12 months remain a matter of debate. The purpose of the present work was to evaluate the C2 target ranges on CsA monitoring after the first year in stable kidney transplant patients. METHODS: We studied 142 patients, 94 on CsA-steroids and 48 on triple therapy (CsA-azathioprin-steroids), transplanted for 104+/-42 months and with a serum creatinine of 1.53+/-0.52 mg/dl. C2 and C0 measurements were performed at baseline and at least twice more during the year of follow-up. RESULTS: The mean annual C2 blood levels in double therapy patients showed C2 in 23 (24.5%) of <600 ng/ml; in 53 (56.4%) of between 600 and 850 ng/ml; and in 18 patients (19.1%) of >850 ng/ml. In the triple therapy group, C2 in 12 (25%) was <500 ng/ml, in 24 (50%) between 500 and 700 ng/ml and in 12 patients (25%) >700 ng/ml. In both groups, higher C2 levels were associated with a better absorption of the drug measured by the ratio C2/C0 and C2/dose. There were no differences in incidence of infections, need for hospitalization and the presence of hypertension, hyperuricaemia, hypercholesterolaemia or diabetes between patients with low and high C2 blood levels. However, serum creatinine was higher in triple therapy patients with lower C0 levels (P = 0.004). In 135 patients (90 on double and 45 on triple therapy), renal function remained stable during follow-up and 120 of them (89%) had C2 values under the recommended ranges. CONCLUSIONS: C2 monitoring in maintenance patients enabled us to identify overexposure to CsA. Target levels of C2 should be adjusted according to the immunosuppressive regime. C2 levels between 600 and 800 ng/ml in double therapy patients and between 500 and 700 ng/ml in triple therapy patients are sufficient to give an adequate immunosuppression. The superiority of C2 with respect to C0 levels could not be demonstrated.

Adult↗

Renal function: defining long-term success.

One of the leading causes of late graft loss is chronic allograft nephropathy, characterized in part by deteriorating renal function. Registry data have demonstrated that renal function within the first year post-transplant is an important predictor of long-term transplant outcome, with serum creatinine concentrations < or =1.5 mg/dl at 6 or 12 months being associated with the highest rate of 5 year graft survival. These findings are supported by a retrospective, pooled analysis of two multicentre trials in the USA, as well as by our own data showing that serum creatinine concentrations may be predictive of long-term survival as early as 1 month post-transplant. Analysis of 216 renal transplantations carried out at our centre (1996-2000) using immunosuppressive therapy based on tacrolimus, corticosteroids and azathioprine (n = 51) or mycophenolate mofetil (MMF; n = 70) vs ciclosporin microemulsion, azathioprine and corticosteroids (n = 95) showed that the best 3 year graft survival was achieved with tacrolimus/MMF therapy. While serum creatinine concentrations at this time point were similar for the tacrolimus and ciclosporin treatment groups (1.69 and 1.65 mg/dl, respectively), the proportion of patients with functioning grafts was significantly higher in the tacrolimus group (84 vs 67%, P = 0.007). Similar findings of improved renal function or graft outcomes with tacrolimus- vs ciclosporin-based therapy have been reported in other single-centre and multicentre trials and a USRDS registry survey. Accumulating data suggest that renal function compares well between tacrolimus-based and calcineurin inhibitor (CNI)-sparing regimens. Consequently, the vast majority of renal transplant recipients maintain good long-term renal function with tacrolimus cornerstone immunosuppression without adopting CNI minimization or withdrawal strategies.

Calcineurin Inhibitors↗

Effect of hypertension before beginning dialysis on survival of hemodialysis patients.

BACKGROUND: The role of hypertension as a predictor of mortality in hemodialysis patients is controversial. The purpose of this study is to investigate the effect of hypertension before starting hemodialysis therapy on survival of patients without diabetes during renal replacement therapy. METHODS: We reviewed 184 patients starting hemodialysis therapy. Variables studied were age, sex, renal disease, hypertension, comorbidity, vascular calcifications, left ventricular hypertrophy, body mass index, and albumin, cholesterol, and alkaline phosphatase levels. Regarding blood pressure control, three groups were considered: normotensive (NH), controlled hypertensive (c-HT), and uncontrolled hypertensive (uc-HT). RESULTS: The Cox model was performed considering all-cause and cardiovascular mortality. The model was adjusted for age, sex, serum albumin level, vascular calcifications, history of hypertension, and comorbidity. Comorbidity included cardiovascular comorbidity. For all-cause mortality, comorbidity and history of uncontrolled hypertension were independent risk factors (comorbidity relative risk, 1.95; 95% confidence interval, 1.26 to 3.1; P = 0.003; uncontrolled hypertension relative risk, 1.79; 95% confidence interval, 1.15 to 2.8; P = 0.01). For cardiovascular mortality, uncontrolled hypertension was the main risk factor (relative risk, 2.93; 95% confidence interval, 1.68 to 5.12; P = 0.000). Mortality rates were 7.9/100 patient-years for NH, 8.7/100 patient-years for c-HT, and 14.1/100 patient-years for uc-HT patients. CONCLUSION: This study suggests that uncontrolled hypertension in renal patients before starting dialysis therapy is a major risk factor for cardiovascular mortality during hemodialysis. Because hypertension usually starts in the initial stages of renal disease, we emphasize the importance of prompt and adequate control of blood pressure in this population.

Adolescent↗