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F Malberti

Publications and source records attributed to F Malberti.

At least 19 recordsLinked to original sources

The short- and long-term impact of multi-disciplinary clinics in addition to standard nephrology care on patient outcomes.

BACKGROUND: This two country case control study of incident dialysis patients evaluates the outcomes of patients exposed to formalized multi-disciplinary clinic (MDC) programmes vs standard nephrologist care. METHODS: Patients commencing dialysis in two centres (Vancouver, Canada and Cremona, Italy) were evaluated at and after dialysis start, as a function of MDC exposure vs nephrologist care alone. Only chronic kidney disease patients, with longer than 3 months of exposure to nephrology care, who had not previously received kidney replacement therapy were included. Study outcomes included laboratory parameters and survival. The MDC was similar in both countries and average exposure was 6-8 h per patient-year, as compared to 2-4 h for standard care. All patients had equal access to resources prior to dialysis and with respect to dialysis start, as all had been referred to the same local nephrology practices. RESULTS: During the evaluation period 288 patients commenced dialysis after receiving more than 3 months nephrology care prior to dialysis. There were no major demographic differences between the cohorts. Mean duration of nephrology care prior to dialysis was 42 months, and dialysis was initiated at similar low glomerular filtration rate (GFR), though statistically significantly different (7.0 and 8.4 ml/min/m2, P = 0.001). The MDC patients had higher haemoglobin (102 vs 90 g/l, P<0.0001), albumin (37.0 vs 34.8 g/l, P = 0.002) and calcium levels (2.29 vs 2.16 mmol/l, P<0.0001) at dialysis start. Survival was significantly better in the MDC group demonstrated by Kaplan-Meier analysis (P = 0.01). Cox proportional hazards analysis demonstrated standard nephrology clinic vs MDC attendance was a statistically significant independent predictor of death (hazards ratio = 2.17, 95% confidence interval 1.11-4.28) after adjusting for other variables known to impact outcomes. CONCLUSIONS: This analysis of outcomes in two different countries suggests that despite equal and long exposure to nephrology care prior to dialysis, there appears to be an association of survival advantage for those patients exposed to formalized clinic care in addition to standard nephrologist follow-up. While other known predictors of survival such as adequacy of dialysis and severity of illness measures were not included in the model, those parameters require time on dialysis to be accumulated. Thus, the data do suggest that knowledge of patient status at the time of dialysis start is important. Further research is needed to determine which specific components of care both prior to dialysis and after its commencement are most important with respect to outcomes.

Adult↗

Von Willebrand factor and autoantibodies against oxidized LDL in hemodialysis patients treated with vitamin E-modified dialyzers.

Oxidant stress is a well known cause of damage in the atherosclerotic process. Vitamin E is one of the most promising natural antioxidants. In this study we investigated if a vitamin E-coated dialyzer was able to reduce the plasma levels of auto-antibodies against oxidized-LDL, von Willebrand factor (vWf) and thrombomodulin (TM) as markers of endothelial damage. In this controlled 6-month prospective study, we investigated these markers in two matched groups (n=16 each) of patients on regular hemodialysis not yet diagnosed for atherosclerosis cardiovascular disease (ACVD) (mean age=58.3+/-7.0 yrs, mean dialysis age=30.1+/-10.0 months), in which cellulosic (CLS) and vitamin E-modified dialyzers (CLE) were compared. At inclusion all the patients were treated with CLS. Then, the study group was shifted to CLE for 6 months. At baseline the patients showed normal levels of vitamin E and high levels of oxLDL-Ab, vWf and TM compared to healthy subjects. In the CLE group oxLDL-Ab and vWf, but not TM levels, decreased progressively (from 472+/-287 to 264+/-199 mU/mL, p<0.0001 and from 101.1+/-7.5% to 76.7+/-18.5%; p<0.001, respectively), and vitamin E increased from 4.40+/-0.81 to 7.81+/-1.16 microg/mg of cholesterol. At the end of the study, 8 of the patients treated with CLE were randomly selected and went back to the membrane without Vitamin E for six months. They showed an significant increase in OxLDL-Ab and vWf levels and a significant reduction in tocoferol levels. In conclusion, CLE compared to cellulosic dialyzers can lower some indices of damage to LDL and endothelial cells.

Adult↗

Impact of blood and dialysate flow and surface on performance of new polysulfone hemodialysis dialyzers.

Optimization of hemodialysis treatment parameters and the characteristics of the dialyzer are crucial for short- and long-term outcome of end stage renal disease patients. The new high-flux membrane Helixone in the dialyzer of the FX series (Fresenius Medical Care, Germany) has interesting features, such as the relationship of membrane thickness and capillary diameter which increases middle molecule elimination by convection, as well as higher capillary packing and microondulation to improve the dialysate flow and distribution. Blood flow, dialysate flow and surface area are the main determinants of the performance of a dialyzer, however the impact of each parameter on small and middle molecule clearance in high flux dialysis has not been well explored. In order to find the best treatment condition for the new dialyzer series, we evaluated urea, creatinine, phosphate clearances and reduction rate of beta2-microglobulin in ten stable patients treated with different blood flows (effective Qb 280 and 360 ml/min), dialysate flow (Qd 300 or 500 ml/min) and dialyzer surfaces (1.4 and 2.2 m2, FX60 or FX100). KoA and Kt/V were also calculated. Blood flow, dialysate flow and surface area demonstrated a significant and independent effect on clearance of urea, creatinine and phosphate, as well as on Kt/V. Small solute clearance was stable over the treatment. In contrast to small solutes, reduction rate of beta2-microglobulin was related to increasing dialyzer surface only. The new dialyzer design of the FX series proves highly effective due to improved dialysate distribution and reduced diffusive resistance as shown by the small solute clearance. A high reduction rate of beta2-microglobulin is favored by improved fiber geometry and pore size distribution. These findings have potential long-term benefits for the patient.

Aged↗

Comparison of mortality in ESRD patients on convective and diffusive extracorporeal treatments. The Registro Lombardo Dialisi E Trapianto.

BACKGROUND: The aim of this study was to evaluate the effect of convective [hemodiafiltration (HDF) or hemofiltration (HF)] versus diffusive treatments [hemodialysis (HD)] on end-stage renal disease (ESRD) patient mortality and dialysis-related amyloidosis (DRA) using data from the Lombardy Registry. METHODS: For this purpose, 6, 444 patients (aged 56.4 +/- 15.6 years, females 39.5%, diabetics 10. 6%) who started renal replacement therapy (RRT) on HD, HDF, or HF between 1983 and 1995 were considered. A total of 1,082 patients were treated with HDF or HF (first choice in the case of 188), with a median follow-up of 29.7 months. The median follow-up of the 6,298 patients on HD (first choice in the case of 6256) was 22.4 months. The time of survival on dialysis to carpal tunnel syndrome (CTS) surgery was evaluated as a hard marker of DRA morbidity. Survival was compared by means of the Cox proportional regression hazards model, using CTS surgery and all deaths as events for morbidity and mortality, respectively. Explanatory covariates were age, gender, and comorbidities; dialysis modality was tested as a time-dependent covariate. RESULTS: The relative risk (RR) for CTS surgery was significantly higher in older patients [RR = 1.04 per year of age on admission to RRT, 95% confidence interval (CI) 1.02 to 1.06; P = 0. 0001], in diabetics (RR = 2.63, 95% CI 1.30 to 5.31; P = 0.0007), and in patients with heart disease (RR = 5.36, 95% CI 2.27 to 12.68 P = 0.0001). Adjusting for age and diabetic status, the RR for CTS surgery was 42% lower in the patients treated with HDF or HF (RR = 0. 58, 95% CI 0.35 to 0.95, P = 0.03). The RR for mortality, adjusted for age, gender, and comorbidities, was 10% lower in patients treated with HDF or HF (RR = 0.90, 95% CI 0.76 to 1.06; P = NS). CONCLUSION: These results support the hypothesis that convective treatments are associated with a nonsignificant trend toward better survival and significantly delay the need for CTS surgery. An older age and the presence of diabetes and heart disease are other important risk factors for CTS surgery. These results could have an important clinical impact given the relevance of DRA in dialysis patient morbidity.

Adult↗

The PTH-calcium curve and the set point of calcium in primary and secondary hyperparathyroidism.

BACKGROUND: The regulation of PTH secretion by calcium is altered in patients with primary hyperparathyroidism (HPT). A similar abnormality may occur in secondary HPT, but comparisons of PTH secretion in normal subjects and those with secondary HPT have given contrasting results. Differences in baseline serum ionized calcium (ICa) may partly account for these conflicting results. The aim of the present study was to evaluate whether the regulation of PTH secretion by calcium differs from normal in patients with primary and secondary HPT and to determine whether serum calcium concentration per se can affect the set point of calcium and the PTH-calcium relationship. METHODS: The PTH-ICa relationship and the set point of ICa were evaluated in 19 patients with primary HPT (1-HPT), 16 normocalcaemic patients with secondary HPT (2-HPT; PTH 344+/-191 pg/ml), 19 hypercalcaemic patients with secondary HPT (3-HPT; PTH 806+/-254 pg/ml) and 14 healthy volunteers, by inducing hypocalcaemia and hypercalcaemia in order to maximally stimulate or inhibit PTH secretion. In five 1-HPT patients the PTH-ICa curve was restudied after normalization of serum ICa by pamidronate. Parathyroid gland volume was determined by measuring gland size at parathyroidectomy or by means of high-resolution color Doppler ultrasonography. RESULTS: In 1-HPT patients the PTH-ICa curve, constructed using maximal PTH secretion induced by hypocalcaemia as 100%, was shifted to the right, the set point of ICa was increased, and the slope of the curve was reduced when compared to normal subjects. After normalization of baseline serum ICa by pamidronate, a shift of the PTH-ICa curve towards normal and a reduction in the set point of ICa was observed. However, basal PTH and maximal PTH secretion induced by hypocalcaemia increased, minimal PTH secretion induced by hypercalcaemia remained increased and the slope of the curve did not change significantly. The alterations in the PTH-ICa relationship in hypercalcaemic patients with secondary HPT were similar to those found in 1-HPT patients. In normocalcaemic patients with secondary HPT baseline PTH, maximal and minimal PTH secretion and parathyroid gland size were reduced compared to 3-HPT patients. Compared to normal subjects, 2-HPT patients showed greater calcium-induced minimal PTH secretion. The increase in non-suppressible PTH secretion resulted in a rightward shift of the PTH-ICa curve and an increase in the set point of ICa. A strong correlation was found, in both primary and secondary HPT, between the set point of ICa and baseline serum ICa, and between parathyroid gland size and baseline PTH, maximal PTH and minimal PTH. Multivariate regression analysis showed that baseline serum ICa was the main determinant of the set point of ICa in both primary and secondary HPT. CONCLUSIONS: (i) The regulation of PTH secretion by calcium is abnormal in secondary as well as in primary HPT. (ii) Parathyroid gland enlargement in secondary HPT is associated with reduced sensitivity to serum ICa and resistance of parathyroid gland to calcium-mediated PTH suppression, resulting ultimately in PTH hypersecretion, despite hypercalcaemia. (iii) The set point of calcium is strongly dependent on baseline serum calcium, and the PTH-ICa relationship can be affected by variations in serum ICa concentrations. Thus, when the set point of calcium and the PTH-ICa relationship are evaluated, possible differences in baseline serum ICa concentration among the patients should be taken into account.

Calcium↗

Ten years experience of renal replacement treatment in the elderly.

UNLABELLED: Elderly patients constitute an increasing segment of the end-stage renal disease population beginning renal replacement therapy (RRT) in the Western Countries. In this study we studied 2447 end-stage renal disease (ESRD) patients who started renal replacement treatment (RRT) in Lombardy between 1983 and 1992 at the age of 65 or older, with particular emphasis on survival and morbidity. In the last decade the number of elderly patients admitted yearly to RRT increased from 113 [102 per million population (pmp), 20% of all accepted patients] in 1983 to 375 (282 pmp, 42% of all accepted patients) in 1992. The most frequent primary nephropathies in 1992 were glomerulonephritis (21% vs 25% in 1983), vascular diseases (18% vs 13%) and diabetes (12% vs 7%). The use of acetate HD and IPD declined over the 10 years period from 49 to 11% and from 26 to 5%; that of bicarbonate HD and CAPD increased from 3 to 46% and from 26 to 32%. Hospitalization rate was related to age, sex, presence of systemic nephropathies or malignancy, but not to treatment modality. The main causes of death in 1992 were cardiovascular diseases (53 vs 42% in 1983) and cachexia (24 vs 18%). The survival rate of all elderly patients was 64, 39 and 13% at 2, 4 and 8 years. The covariates affecting patient survival (Cox model) were the presence at the start of RRT of systemic nephropathies (Hazard ratio 1.7), systemic atherosclerosis (1.6), other comorbidity conditions (1.38) and peritoneal dialysis (1.31). CONCLUSIONS: (1) The progressive increase in the number of patients admitted to RRT in the last decade is due to loose criteria of acceptance of elderly patients (increase in the acceptance rate of diabetics and patients with vascular disease), (2) patients' survival is affected by the presence of comorbid conditions at the start of RRT, (3) the worse survival rate in peritoneal dialysis could result from a hidden negative selection of patients, unmeasured by Cox analysis.

Adult↗

Long-term effects of intravenous calcitriol therapy on the control of secondary hyperparathyroidism.

Although high-dose intravenous calcitriol has been shown to be effective in suppressing parathyroid hormone (PTH) secretion in dialysis patients with secondary hyperparathyroidism, an increasing number of patients is refractory to treatment. Only a few studies have evaluated the factors that can predict a favorable response to calcitriol, but contrasting results have been reported. This study was performed to evaluate the effect of high-dose intravenous calcitriol on parathyroid function and to investigate the factors that can predict a favorable response to treatment. Thirty-five dialysis patients were selected for intravenous calcitriol treatment (2 microg after dialysis for 12 months) because of increased PTH levels (>325 pg/mL). Before starting the treatment, the set point of calcium and the PTH-ionized calcium (ICa) curve was evaluated in each patient by inducing hypocalcemia and, 1 week later, hypercalcemia to maximally stimulate or inhibit PTH secretion. Parathyroid glands were assessed by high-resolution color Doppler ultrasonography. Throughout the study, calcium carbonate or acetate dosage was modified to maintain serum phosphate less than 5.5 mg/dL. Hypercalcemia was managed by reducing dialysate calcium to 5 mg/dL and, if necessary, calcitriol dose. The therapeutic goal was to reduce PTH levels below 260 pg/mL while maintaining normocalcemia. The patients who achieved the therapeutic goal were considered responders. Taking the data from the 35 patients together, we observed a significant decrease (P < 0.01) in alkaline phosphatase (from 252 +/- 106 IU/L to 194 +/- 81 IU/L) and PTH (from 578 +/- 231 pg/mL to 408 +/- 291 pg/mL), and a significant increase in serum ICa (from 5.1 +/- 0.2 mg/dL to 5.3 +/- 0.2 mg/dL; P < 0.001) after calcitriol therapy. PTH changes after therapy were not correlated to serum ICa changes, serum phosphate levels during treatment, and calcitriol dose. The response to therapy was heterogeneous because PTH levels markedly decreased over the treatment period in 18 responsive patients, whereas they increased or remained unchanged in 14 of 17 nonresponders. In three additional refractory patients, there was a decline in PTH of 20% to 35%, but this decline was associated with hypercalcemia. Pretreatment parathyroid gland size, serum ICa, PTH, maximal PTH induced by hypocalcemia, minimal PTH induced by hypercalcemia, the set point of ICa, and the ICa levels at which maximal PTH secretion and inhibition occurred were higher in the 17 refractory patients than in the 18 responsive patients. However, logistic regression analysis showed that among these parathyroid function parameters, the only significant predictors of a favorable response to calcitriol therapy were the parathyroid gland size and the set point of ICa. Throughout the study, serum phosphate and calcitriol dose were comparable in the two groups. In conclusion, the response to intravenous calcitriol therapy in dialysis patients with secondary hyperparathyroidism is heterogeneous, consisting of patients who are either responsive or refractory to treatment; refractoriness can be predicted by parathyroid volume and calcium set point.

Calcitriol↗

Different effects of calcitriol and parathyroidectomy on the PTH-calcium curve in dialysis patients with severe hyperparathyroidism.

BACKGROUND: The PTH-calcium sigmoidal curve is shifted to the right, the slope of the curve is steeper, and the set point of calcium is increased in dialysis patients with secondary hyperparathyroidism, compared to patients with low-turnover bone disease. These findings could be related to increased parathyroid cell mass and increased sensitivity of parathyroid cells to serum calcium variations in these patients. Calcitriol therapy has been documented to reduce PTH levels by shifting the curve to the left and downward. The effect of a surgical reduction of parathyroid gland mass on the PTH-calcium curve has not yet been investigated. In this study we compared the effects of calcitriol and subtotal parathyroidectomy (PTH) on the dynamics of PTH secretion in response to acute changes of serum calcium in two groups of dialysis patients with severe hyperparathyroidism. METHODS: Fourteen dialysis patients treated for 6 months with high-dose i.v. calcitriol (1-2 micrograms thrice weekly, and 10 dialysis patients who underwent subtotal PTx were studied. The PTH-calcium relationship obtained by inducing hypo- and hypercalcaemia means of low and high calcium dialysis was evaluated before and 2-6 months after treatment. RESULTS: Both calcitriol and subtotal PTx significantly decreased PTH (respectively from 797 +/- 595 to 380 +/- 244 and from 1036 +/- 250 to 70 +/- 34 pg/ml), as well as maximal PTH response to hypocalcaemia (PTHmax), and maximal PTH suppression during hypercalcaemia ( PTHmin). When the PTH-calcium curves were constructed using PTHmax as 100% to factor for differences in absolute PTH levels and to provide an assessment of individual parathyroid cell function, a shift of the sigmoidal curve to the left and downward, and a significant decrease in the set point of ionized calcium (from 1.31 +/- 0.05 to 1.26 +/- 0.05 and from 1.36 +/- 0.09 to 1.22 +/- 0.07 mmol/l) was documented with both treatments. However, the slope of the PTH-calcium curve increased after subtotal PTx indicating that the sensitivity of the parathyroid cell to serum calcium changes increased with PTx, while on the contrary it decreased with calcitriol. CONCLUSIONS: PTH secretion decreases proportionally more with calcitriol than with surgery for a given decrease in the functional mass of parathyroid cells. The change in the PTH-ICa sigmoidal curve induced by subtotal PTx is due to the removal of a large mass of parathyroid tissue with advanced hyperplasia.

Calcitriol↗

Survival of diabetic patients on peritoneal dialysis or hemodialysis.

Our objective was to analyze the survival of diabetic patients on renal replacement therapy and to compare their survival on extracorporeal and on peritoneal dialysis. All data regarding diabetic patients admitted to dialysis between 1 January 1983 and 31 December 1993 were collected by means of individual patient questionnaires sent to all of the 44 regional Renal Units (100% answers) of Lombardy, Italy. Cox proportional hazards model, stepwise procedure, was applied in order to select the covariates significantly associated with survival. Age (at baseline), sex, type of diabetes, initial modality of treatment (hemodialysis or peritoneal dialysis), and initial clinical risk factors (malignancies, serious heart disease, vascular disease, cirrhosis of the liver, cachexia) were considered. Descriptive analysis of survival was performed using the Kaplan-Meier technique. The survival of all diabetic patients (895) was 86.5% at one year, 52% at three years, and 34% at five years. The main causes of the 488 deaths of diabetic patients were cardiovascular diseases (56%), cachexia (18%), and infections (11%). The relative death risk of patients on peritoneal dialysis versus those on hemodialysis, after taking into account the main comorbid conditions, did not significantly differ from 1, as estimated by the Cox proportional hazards regression model. Five-year survival of diabetic patients was 34%, and no differences were found between peritoneal dialysis and hemodialysis as far as mortality is concerned.

Adult↗

Effect of CAPD and hemodialysis on parathyroid function.

UNLABELLED: A high incidence of low turnover bone disease (LTBD) has been reported in predialysis and dialysis uremic patients, despite parathyroid hormone (PTH) levels two- to four-fold the upper normal limit. The aim of this study was to evaluate the trend of PTH in uremic patients after admission to continuous ambulatory peritoneal dialysis (CAPD) or hemodialysis (HD). Thus, we evaluated 53 patients (27 CAPD and 26 HD) of 73 consecutive uremic patients starting CAPD or HD from 1992, who had at least one year follow-up on dialysis. HD and CAPD patients were comparable for age, nephropathy, and duration of uremia. All the patients had been treated with calcium carbonate (CaCO3) as the sole phosphate binder during the predialysis period. At the time of admission to dialysis PTH was > 260 pg/mL (fourfold above the upper normal limit) in 12 CAPD and 9 HD patients, between 130 and 260 pg/mL in 6 CAPD and 5 HD patients, and < 130 pg/mL in 9 CAPD and 12 HD patients. Bone biopsy, performed in 22 patients, showed LTBD in 10 of 12 patients with PTH < 130 pg/mL and high bone turnover in 8 patients with PTH > 260 pg/mL. Patients were treated with a dialysate calcium (Ca) of 1.75 mmol/L and were given CaCO3 to maintain serum phosphate < 5 mg/dL. Oral calcitriol was given if they developed hypocalcemia (< 9 mg/dL). Hypercalcemia (> 10.5 mg/dL) occurred in 13 CAPD and 17 HD patients, and was managed by discontinuation of calcitriol and reduction of dialysate Ca to 1.25-1.5 mmol/L. A significant decrease in PTH and alkaline phosphatase was observed in both groups after six and 12 months of treatment. After one year of CAPD, PTH was > 260 pg/mL in 3 patients, between 130 and 260 pg/mL in 4 (all on calcitriol), and < 130 pg/mL in 20 patients (17 on calcitriol, but only 2 mild hypercalcemic). After one year of HD, PTH was > 260 pg/mL in 3 patients, 130-260 pg/mL in 5 (all on calcitriol), and < 130 pg/mL in 18 (11 on calcitriol, 1 mild hypercalcemic). IN CONCLUSION: (1) about 40% of predialysis patients treated with CaCO3 showed PTH levels suggestive of LTBD; (2) the proportion of patients with low PTH increases after one year on CAPD or HD, even though calcemia was maintained within the normal range; (3) suppressed PTH levels are associated with calcitriol therapy rather than dialysis modality; and (4) secondary hyperparathyroidism improves in most patients after one year on CAPD or HD.

Adolescent↗

1983 to 1992: report on regular dialysis and transplantation in Lombardy.

This 1993 report of the Lombardy Regional Dialysis and Transplant Registry refers to all the data collected between January 1, 1983, and December, 31, 1992, by means of individual patient questionnaires sent to all of Lombardy's 44 renal units (100% replies). The number of patients recorded by the Registry as being alive progressively increased; by the end of 1992, the number was 6,014 (655 patients per million population): 4,770 patients were on dialysis treatment (515 patients per million population, 79.3%) and 1,244 patients (140 patients per million population, 20.7%) had received a kidney graft. The acceptance rate for dialysis increased from 64 per million population in 1983 to 102 per million population in 1992; the increase in the transplant rate was much lower (from 18.7 to 21.3 per million population). The percentage of primary nephropathies in the new patients accepted for dialysis treatment were 22.0% glomerulonephritis, 13.8% interstitial nephritis, 15.2% vascular diseases, 10.1% cystic kidney, and 10.6% diabetes. The use of acetate hemodialysis declined over the 10-year period from 72.4% to 17.5%; that of bicarbonate hemodialysis increased from 8.8% to 50.1% and that of hemodiafiltration increased from 0.2% to 11.1%. The prevalence of hospital hemodialysis was stable, ranging from 55.4% to 52.2%; home hemodialysis decreased from 15.7% to 5.3%, continuous ambulatory peritoneal dialysis increased from 13.3% to 19.6%, and limited care increased from 13.7% to 22.4%. The crude death rate increased from 7.5% in 1983 to 10.5% in 1992. The survival rate (Kaplan-Meier) of all patients on dialysis was 78.8% at 2 years, 62.2% at 4 years, and 40% at 8 years; for transplanted patients, the survival and graft survival rate at 2 years was, respectively, 95% and 86%. The relative death risk of the patients on peritoneal dialysis with respect to those on hemodialysis was 1.419, as estimated by the Cox proportional hazard regression model. The main causes of deaths of patients on dialysis treatment during the year 1992 were cardiovascular diseases (47.0%) and cachexia (19.5%); in transplanted patients, they were cardiovascular diseases (36.6%) and infections (34%). Registries are not only important for planning health care but are also very useful instruments for clinical research.

Adult↗

Prognosis of diabetic patients on dialysis: analysis of Lombardy Registry data.

METHODS: This 1993 Lombardy Registry Report refers to all of the data regarding treated diabetics collected between 1 January 1983 and 31 December 1992 by means of individual patient questionnaires sent to all of Lombardy's 44 Renal Units (100% replies). RESULTS: The acceptance rate of diabetics for dialysis increased from 5.6 in 1983 to 10.4 patients per million population in 1992 for a total of 731 patients (379 type I, 352 type II). The yearly percentage of new diabetics increased from 9 to 11%, and the proportion of patients with two or more risk factors increased from 14.7% in 1983-1987 to 22.0% in 1988-1992. The use of peritoneal dialysis declined over the 10-year period from 50% in 1983-1984 to 30% in the last 2 years. The difference in age of the patients on peritoneal and haemodialysis tended to decrease. The survival of all diabetic patients was 82% at 1 year, 48% at 3 years, and 28% at 5 years. The relative death risk of the patients on peritoneal dialysis compared to those on haemodialysis, after taking into account age and the main comorbid conditions (type of diabetes, severe vascular disease, cirrhosis and the generic other risk factors), did not differ significantly from one, as estimated by the Cox proportional hazard regression model (344 events). The main causes of death of these patients were cardiovascular diseases (about 50.0%), cachexia (from 17.2% in 1983/1984 to 22% in 1991/1992), and infection (about 11%). The mean hospitalization rate was higher in diabetics than in patients with standard nephropathies (i.e. in 45-64-year-old patients: 32.8 versus 13.9 days/patient-year). CONCLUSION: Multivariate analysis showed that age, type of diabetes, severe vascular disease, cirrhosis, and the generic other risk factors were significantly related to survival; but diabetic patients without any baseline risk factors also had a poor prognosis and morbidity was very high in absolute terms. Medical care therefore needs to be improved in order to reverse prognostic risk factors and prevent cardiovascular and noncardiovascular events.

Adult↗

Calcium balance and serum ionized calcium fluctuations in on-line haemodiafiltration in relation to ultrafiltration rate and dialysate calcium concentration.

The use of high ultrafiltration rates in haemodiafiltration (HDF) has been suggested for improving the clearance of small and large molecules. This strategy has become economically applicable with the development of safe techniques for on-line production of sterile infusate from dialysate, which enables us to infuse large substitution fluid volumes without further increasing the cost of sessions. The effect of increasing the ultrafiltration rate in HDF on electrolyte balance has not yet been evaluated. The aim of this study was to evaluate the effects of variations of the ultrafiltration rate on calcium kinetics in HDF using three different dialysate calcium concentrations. Since the increase in ultrafiltration rate augments the convective calcium loss, variations of intrasession calcium balance could result from modifications of the ultrafiltration rate. In the present study we found no significant variations in calcium balance and serum ionized calcium (iCa) levels during on-line HDF treatment when increasing the mean ultrafiltration rate from 60 to 100 ml/min in the presence of an adequate and corresponding increase in the infusion rate (from 2.5 to 5 l/h). During the balance studies, pretreatment serum iCa was on the average 1.32 mmol/l and weight loss 3.2 kg. Mean calcium loss during treatment was 2.8 and 3.3 mmol at infusion rates of 2.5 and 5 l/h with 1.63 mmol/l of calcium in both the dialysate and infusate; calcium loss rose to 5.9 and 11.2 mmol at infusion rates of 2.5 l/h and to 5.7 and 14.2 mmol at infusion rates of 5 l/h when the dialysate and infusate calcium was reduced respectively to 1.5 and 1.25 mmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium↗

High-dose oral calcitriol and zero calcium peritoneal solutions in CAPD patients with refractory secondary hyperparathyroidism.

We evaluated the effect of pulse oral calcitriol (4 micrograms three times weekly for 6 months) on parathyroid function in nine CAPD patients with hyperparathyroidism refractory to conventional low-dose oral calcitriol. Zero calcium peritoneal solutions were used to prevent the development of hypercalcaemia. The peritoneal loss of calcium increased from 168 +/- 40 to 417 +/- 48 mg/day using zero calcium solutions. Pulse oral calcitriol resulted in a significant decrease in PTH (from 617 +/- 272 to 382 +/- 299 pg/ml) by the 15th day of therapy, while serum iCa did not change from baseline. During the first month of therapy the mean PTH levels remained significantly reduced compared to baseline, thereafter PTH increased in four of nine patients. Hyperphosphataemia was not satisfactorily controlled in four patients, despite large amounts of binders used; seven of nine patients developed hypercalcaemia and required either the substitution of calcium acetate for calcium carbonate or reduction of calcitriol dose. Three patients showed a progressive increase in PTH. In conclusion our data suggest that in most CAPD patients with severe hyperparathyroidism oral calcitriol pulse therapy is not effective in maintaining a permanent suppression in PTH levels.

Administration, Oral↗