Treatment of proteinuria with lercanidipine associated with reninangiotensin axis-blocking drugs

Aim. Most calcium antagonists do not seem to reduce microalbuminuria or proteinuria. We have tried to assess the antiproteinuric effect of a calcium channel blocker, lercanidipine, in patients previously treated with ACE inhibitors or angiotensin receptor blockers.Design and methods. The study included 68 proteinuric (>500 mg/day) patients (age 63,1±12,9 years, 69,1 % males and 30,9 % females). All patients were receiving ACE inhibitors (51,4 %) or angiotensin II receptor blockers (48,6 %) therapy but had higher blood pressure (BP) than recommended for proteinuric patients (<130/80 mm Hg). Patients were clinically evaluated one, three, and six months after starting treatment with lercanidipine (20 mg/day). Samples for urine and blood examination were taken during the examination. When needed, a third drug was added to treatment. Creatinine clearance was measured using 24 h urine collection.Results. BP significantly decreased from 152±15/86±11 mm Hg to 135±12/77±10 mm Hg at six months of follow-up (p<0,001). After six months of treatment, the percentage of normalized patients (BP <130/80 mm Hg) was 42,5 %, and the proportion of patients whose BP was below 140/90 mm Hg was 58,8 %. Plasmatic creatinine did not change nor did creatinine clearance. Plasmatic cholesterol also decreased from 210±48 to 192±34 mg/dL (p<0,001), as did plasma triglycerides (from 151±77 to 134±72 mg/dL,p=0,022). Basal proteinuria was 1,63±1,34 g/day; it was significantly (p<0,001) reduced by 23 % at the first month, 37 % at three months, and 33 % at the last visit.

Conclusion. Lercanidipine at 20 mg dose, associated with renin-angiotensin axis-blocking drugs, showed a high antihypertensive and antiproteinuric effect. This antiproteinuric effect seems to be dose-dependent as compared with previous reports and proportionally higher than blood pressure reduction.

Treatment of proteinuria with lercanidipine associated with renin-angiotensin axis-blocking drugs

OBJECTIVE

Most calcium antagonists do not seem to reduce microalbuminuria or proteinuria. We have tried to assess the antiproteinuric effect of a calcium channel blocker, lercanidipine, in patients previously treated with ACE inhibitors or angiotensin receptor blockers.

DESIGN AND METHODS

The study included 68 proteinuric (> 500 mg/day) patients (age 63.1 +/- 12.9 years, 69.1% males and 30.9 females). All patients were receiving ACE inhibitors (51.4%) or angiotensin II receptor blockers (48.6%) therapy but had higher blood pressure than recommended for proteinuric patients (<130/80 mmHg). Patients were clinically evaluated one, three, and six months after starting treatment with lercanidipine (20 mg/day). Samples for urine and blood examination were taken during the examination. When needed, a third drug was added to treatment. Creatinine clearance was measured using 24 h urine collection.

RESULTS

BP significantly decreases from 152 +/- 15/86 +/- 11 mmHg to 135 +/- 12/77 +/- 10 mmHg at six months of follow-up (p < 0.001). After six months of treatment, the percentage of normalized patients (BP < 130/80 mmHg) was 42.5%, and the proportion of patients whose BP was below 140/90 mmHg was 58.8%. Plasmatic creatinine did not change nor did creatinine clearance. Plasmatic cholesterol also decreased from 210 +/- 48 to 192 +/- 34 mg/dL (p < 0.001), as did plasma triglycerides (from 151 +/- 77 to 134 +/- 72 mg/dL, p = 0.022). Basal proteinuria was 1.63 +/- 1.34 g/day; it was significantly (p < 0.001) reduced by 23% at the first month, 37% at three months, and 33% at the last visit.

CONCLUSIONS

Lercanidipine at 20 mg dose, associated to renin-angiotensin axis-blocking drugs, showed a high antihypertensive and antiproteinuric effect. This antiproteinuric effect seems to be dose-dependent as compared with previous reports and proportionally higher than blood pressure reduction.

Evolution of Suboptimal Renal Transplantations: Experience of a Single Spanish Center

The increase in patients on dialysis awaiting transplantation has led to the use of grafts from suboptimal donors. The aim of this study was to analyze the function of suboptimal grafts. The secondary objectives were to study vascular and urological complications, as well as delayed renal function and acute rejection episodes. The study included 135 transplantations performed over 4 years with 27% of grafts being from suboptimal donors. Early graft loss was 12%, of which 69% were due to vascular thrombosis. These thromboses were more frequent among grafts from suboptimal donors (30% vs 4%, P < .001). There were no significant differences between the groups in the incidence of acute rejection episodes (17% vs 13%) or delayed graft function (14% vs 13%). A greater incidence of urologic complications was observed among recipients of grafts from older donors. The 1-year creatinine clearance was significantly lower among recipients of grafts from older donors (73 +/- 19 vs 51 +/- 14 mL/min, P < .0001). Sequential immunosuppressive therapy resulted in a lack of significant differences in creatinine clearance at 6 months, 1 year, or 2 years after transplantation between suboptimal grafts with cold ischemia greater or less than 20 hours or in warm ischemia greater or less than 60 minutes. Logistic regression analysis showed that the best determinant of graft loss was donor age older than 60 years. Accordingly, grafts from suboptimal donors were more likely to be lost during the first month after transplantation, particularly because of thrombosis, which was not due to a higher degree of technical complexity of the transplant operation.

[Serum uric acid and C-reactive protein levels in patients with chronic kidney disease]

Either inflammation or hyperuricemia has been related with increased cardiovascular risk and mortality. A hypothetical relationship between serum uric acid levels (SUA) and inflammatory markers has never been tested in chronic kidney disease (CKD) patients. The purpose of this study was to determine the prevalence of increased C-reactive protein (CRP) levels in CKD patients, and to test the hypothesis of a relationship between SUA and CRP levels. The study group consisted of 337 patients (174 males, mean age 63 +/- 16 years) with advanced chronic renal failure not yet on dialysis. None of them had overt inflammatory or infectious diseases. High sensitivity CRP levels were analyzed as a binary (above or below median value), or continuous variable (log-transformed CRP), by multiple logistic or linear regression analysis, respectively. Demographics, clinical, and biochemical characteristics, including SUA levels, were the variables tested in these analysis. In a subset of 169 patients without diabetes, the same analysis were carried out, with the inclusion of fasting insulin levels and HOMA-IR as independent variables. Median CRP level was 3.25 mg/L, and mean SUA level was 7.59 +/- 1.94 mg/dl. Patients with CRP levels above the median had significantly higher mean SUA level than that of the rest of study patients (7.93 +/- 1.79 vs 7.24 +/- 2.03 mg/dl, p = 0.001). SUA levels correlated significantly with log-transformed CRP levels (r = 0. 16, p = 0.0022). The relationship between SUA and CRP levels remained statistically significant after adjustment for age, sex, comorbid index, obesity, residual renal function, diuretic and allopurinol treatment, in the multivariate logistic and linear regression models (OR: 1.296, p = 0.0003; and beta: 0.204, p = 0.0002). The significant association between SUA and CRP levels did not change when HOMA-IR and fasting insulin levels were included as independent variables in the subset of 169 patients without diabetes. In conclusion, SUA levels are related with CRP levels in CKD patients.

[Obesity and mortality in advanced chronic renal failure patients]

A protective effect of obesity on the mortality of end-stage renal failure patients has been observed in several studies. Most of these studies have been based on prevalent dialysis population. The aim of the present study was to evaluate if obesity has beneficial effects on the survival of advanced chronic renal failure patients. The study group consisted of 376 patients (mean age 63 +/- 15 years) with advanced chronic renal failure not yet on dialysis. Obesity was defined as a body mass index (BMI) > or = 30 kg/m2. Grade of comorbidity was quantified by the method devised by Davies. Survival was analyzed as time from the referral to the predialysis outpatient clinic to patient death, censoring from contributing additional survival data to the analysis following transplantation. Kaplan-Meier analysis was used to test survival differences according to quartiles of BMI, and between obese and nonobese patients. Further analysis were performed, stratifying survival curves by comorbid scores, lean body mass, age, and sex. Cox proportional hazard regression models were used to investigate the best determinants of mortality, and the role of obesity adjusted for other covariates. Median survival time was 1,453 days. During the follow-up time, 158 patients (42%) died. Survival differences among quartiles of BMI were statistically significant (Breslow = 10.7, p = 0.017). Patients within the lowest and the highest quartiles of BMI had higher mortality than the rest of patients. Survival curves between obese and non-obese patients did not differ significantly. However, when patients without comorbidity were studied apart, those with obesity showed worse survival than the rest of patients (log-rank = 7.42, p = 0.0064). Since the effect of obesity on mortality did not follow a proportional hazard pattern throughout the study period, multivariable analysis for mortality was stratified by 18 months intervals. The variables which fitted the best model were: age (Hazard Ratio: 1.04), comorbid score (HR: 2.17), serum albumin (HR: 0.62), GFR at the study entry (HR: 0.91), male gender (HR: 1.48), and obesity (HR: 1.51). In conclusion, obesity had no survival benefit in patients with advanced chronic renal failure. Obesity had a noteworthy impact on early mortality of advanced chronic kidney disease patients without comorbidities.

[Progression of renal insufficiency in the pre-end-stage renal disease setting]

The rate of decline of renal function (RDRF) in the pre-end stage renal disease setting (pre-ESRD) is highly variable. Several factors have been involved as potential modifiers of renal failure progression. This retrospective study attempts to establish which were the main determinants of the RDRF in pre-ESRD patients followed in the predialysis consult. The study group consisted of 230 patients with pre-ESRD not yet on dialysis who were referred to the predialysis consult from January 1998 to July 2002. The mean follow-up time per patient was 356 days. RDRF was assessed as delta of the average of creatinine and urea clearances (CrCl-UCl). Data obtained at time of referral to the predialysis consult were analyzed as potential predictors of the subsequent RDRF. These independent variables included: demographics, comorbid conditions, main hematological and biochemical data, antihypertensive and statin treatment, mean blood pressure, and CrCl-UCl at time of referral. The predictors of delta CrCl-UCl were determined by multiple linear regression analysis. The determinants of the survival without dialysis were established by the Cox regression hazard model, adjusted to renal function at time of referral. Mean CrCl-UCl at time of referral was 10.98 +/- 2.58 ml/min/1.73 m2, and mean delta CrCl-UCl was -0.37 +/- 0.46 ml/min/1.73 m2/month. Patients with diabetic nephropathy and chronic glomerulonephritis had the fastest RDRF, while patients with ischemic nephropathy and chronic interstitial nephritis had the slowest RDRF. Seventy-five patients (46%) required EPO therapy. The best determinants of delta CrCl-UCl were: the 24-hour proteinuria (p < 0.0001), and the hematocrit at time of referral (p = 0.0024). The best determinants of the survival rate without dialysis during the study period were: the proteinuria (in g/24 hours) (R 1, 16; p < 0.0001), the hematocrit at time of referral (OR: 0.88; p < 0.0001), the treatment with EPO (OR: 0.59; p = 0.02), and the diagnosis of diabetes mellitus (OR: 1.59; p = 0.01). In conclusion, apart from the rate of proteinuria, which could represent the best marker of the RDRF in chronic renal diseases, the development of anemia was associated with faster decline in renal function.

[Differences between the glomerular filtration rate estimated by the MDRD equation and the measurement of creatinine and urea clearance in unselected patients with terminal renal insufficiency]

From the results of the Modification of Diet in Renal Disease (MDRD) study, a prediction equation for a more accurate estimate of glomerular filtration rate (GFR), was developed. The present study ais to compare the GFR estimated by MDRD formula and that calculated by the average of creatinine and urea clearances in unselected patients with advanced renal failure. The study group consisted of 320 (163 males) with advanced renal failure not yet on dialysis. Their mean age was 63 +/- 14 years. Diabetic nephropathy was the most common etiology of renal failure (25%). Significant comorbidity was observed in 115 patients. Serum creatinine (Cr), urea and albumin were determined in all patients. Creatinine (Ccr) and urea clearance (Cu) were calculated on a 24-hour urine collection. The GFR was estimated by summing Ccr and Cu, and dividing by two (Ccr-Cu). THe clearances were corrected for a body surface area of 1.73 m2. The MDRD formula for the estimation of GFR included the following parameters: serum Cr, BUN, age, gender and serum albumin. Linear regression analysis and Bland-Altmann plot were utilized to establish the degree of correlation and agreement between both estimations of GFR. The percent differences between the two estimations of GFR was especially analyzed in those subgroups of patients which were not included in the MDRD study (patients older than 70 years, diabetics and those with comorbid conditions). The mean GFR estimated by Ccr-Cu and by MDRD formula were 10.04 +/- 3.10 ml/min and 10.55 +/- 3.60 ml/min, respectively (p < 0.0001). The two parameters correlated significantly (R = 0.76, p < 0.0001). GFR by the MDRD formula tended to overestimate the highest values of Ccr-Cu. The mean percent difference between both methods was 6.5 +/- 23.6. MDRD predictive equation overestimated significantly Ccr-Cu in patients older than 70 years (mean overestimation of 15%), males (10%), diabetics (10%), and mainly in patients with comorbidity (17%). In conclusion, the GFR estimated by MDRD formula is very similar to Ccr-Cu in young uremic patients without comorbidity. However, major discrepancies between these two methods could be observed in older patients, and mainly in those with comorbidity.

[Predictors of early death during dialysis]

The mortality among end-stage renal failure (ESRF) patients undergoing renal replacement therapy (RRT) remains high. An important proportion of these patients die shortly after the initiation of RRT. The present study aims to determine the best predictors for the early mortality in a group of 140 ESRF patients who initiated RRT between october 96 and december 99. The mean age of the study group was 61 +/- 13 years, and the mean follow-up time was 20 +/- 12 months. Diabetic nephropathy was the most prevalent etiology of renal failure (30%). The following data, collected immediately before the initiation of RRT, were included as independent variables: demographic and clinical characteristics, including the nutritional status established by the Subjective Global Assessment (SGA), follow-up time in the predialysis clinic (less or longer than 3 months), EPO therapy, vascular access, renal function (creatinine and urea clearances, and Kt/V urea), hematological and biochemical data including serum albumin, bicarbonate, transferrin, PTH and C-Reactive protein, as well as the protein catabolic rate and the percent of lean body mass normalized for ideal body weight, calculated from the 24 h total urine excretion of nitrogen and creatinine. The Cox proportional hazard regression model, stratified for an age over or less than 65 year, was utilized to determine the best predictors for the mortality during the study period. Sixty percent of patients had at least one comorbid condition, and 35% had cardiovascular diseases. Mild-moderate or severe malnutrition was observed in 48% of patients. The creatinine clearance and Kt/V urea before the initiation of RRT were: 9.50 +/- 2.64 ml/min/1.73 m2 and 1.47 +/- 0.44, respectively. Forty-one patients died during the study period (annual death rate: 17%). The best predictor of mortality was the nutritional status assessed by the SGA (OR: 2.32, IC 95% 1.54-3.48, p < 0.0001). In a second analysis in which the SGA was removed from the model, the previous history of cardiovascular diseases (OR: 2.07, CI 95%: 1.06-4.06, p = 0.032), and the percent of lean body mass/ideal weight (OR: 0.96; IC 95%: 0.93-0.99; p = 0.042), proved to be the best predictor of mortality. In conclusion, nutritional indices prior to the initiation of RRT, and the previous history of cardiovascular diseases were the best predictors of the early mortality in this unselected population on dialysis. Because nutritional status appeared to be a marker of the severity of the comorbid conditions, a better control of the number and severity of these comorbid conditions may be the best way for reducing the mortality in patients on RRT.

Acute effect of hemodialysis with polyacrylonitrile membrane on nerve conduction velocities

AIM

Non cellulosic membranes, as polyacrylonitrile (AN69) improves middle-molecules purification through hemodialysis, and this increased clearance of middle-molecules may have benefical effects on uremic polyneuropathy. We have tried to evaluate this effect comparing nerve conduction velocities before and after hemodialysis with either AN69 or cellulose acetate (CA).

PATIENTS AND METHODS

Eight patients in hemodialysis with AN69 for more than three months (4 men and 4 women, mean age 58.4 +/- 12.9 years, mean time in hemodialysis 9.3 +/- 7.5 months). Motor conduction velocities (MCV) and sensory conduction velocities (SCV) were measured predialysis and postdialysis with AN69 and, one week later, predialysis and postdialysis with CA.

RESULTS

There were no differences neither in Kt/V values (AN69 1.27 +/- 0.36 vs CA 1.16 +/- 0.26) nor in TAC ones (AN69 40.8 +/- 17.4 vs CA 40.8 +/- 21.3 mg/dL). After hemodialysis with AN69 MCV significantly increased (42.0 +/- 3.0 vs 40.6 +/- 2.6 m/s baseline, p < 0.05). SCV was also enhanced (45.3 +/- 2.2 vs 41.1 +/- 3.4 m/s baseline, p < 0.05). After hemodialysis with CA neither MCV changed (42.7 +/- 1.6 vs 42.0 +/- 2.3 m/s baseline), nor did SCV (45.8 +/- 5.8 vs 44.8 +/- 3.0 m/s baseline).

CONCLUSIONS

Hemodialysis with AN69 acutely improved SCV and MCV. This effect was not seen with CA hemodialysis.

[Incidence of diabetic nephropathy in the province of Badajoz along the period from 1990 to 1994]

Current registries provide information only on the number of diabetic patients with end-stage renal failure, more detailed information on the incidence of diabetic nephropathy with incipient renal failure is currently not available. The Nephrology Service of Hospital Infanta Cristina in Badajoz serves a population of approximately 650,000. In the time span between 1.1.90 and 31.12.94 the outpatient clinic and the renal ward had 1,717 admissions for evaluation of renal illness, 166 due to diabetic nephropathy (9.7% of total. Twelve (7.2%) were type I diabetics (mean age, 29.9 +/- 6.2 years), and 154 were type II diabetics (mean age 63.4 +/- 9.8 years). The annual incidence increased from 41.5/mio in 1990 to 61.5/mio in 1994. In parallel, 286 patients were admitted for renal replacement therapy, i.e. 88/mio/year. Of this group 60 patients had diabetes: type I, 8 patients (13.3%, mean age 3.7 +/- 6.4); type II, 52 patients (86.7%, mean age 66.0 +/- 6.6 years). This corresponds to an admission rate for dialysis of 18.5/mio/year (19.6% of all patients), with a increasing incidence rate from 13.8/mio in 1990 to 23.1/mio in 1994. This incidence of diabetic nephropathy is more than two-fold greater than the previously reported incidence by the EDTA registry for Spain, it is six-fold greater that the figure recorded for our region. Although the rates of incidence and prevalence of renal failure due to diabetic nephropathy founded in this study seems still to be lower than those of other developed european countries, it is detected a trend toward an increase of these figures in the latter years.

[Hypercalcemia in a female patient with chronic kidney failure secondary to sarcoidosis: a metabolic study of the calcium metabolism and bone histology]

We describe the case of a 42-year-old woman diagnosed of chronic renal failure secondary to sarcoidosis. Since the beginning of the dialysis treatment she presented episodes of symptomatic hypercalcemia which did not response to calcium restriction diet and a lower calcium concentration in the dialysate. Secondary hyperparathyroidism and aluminium intoxication were biochemically ruled out. Hypercalcemic crisis were associated to 1.25-dihydroxy-vitamin D (1.25-D) serum levels abnormally raised and they responded quickly to low doses of corticosteroids. Subsequently, this treatment had to be withdrawn because of upper gastrointestinal bleeding, and hypercalcemia recurred. Chloroquine phosphate was prescribed with a rapid response to normalize the serum calcium levels. No side effects was recorded. Twelve months later of chloroquine therapy, the patient remained normocalcemic. A bone biopsy showed an active osteopenia without aluminium deposits, hyperparathyroidism signs or granuloma. We discuss about the pathogenesis of hypercalcemia in this case and its relation with abnormal high serum levels of 1.25-D in hemodialysis patients and sarcoidosis.