Edwina Brown

Clinical outcomes, quality of life, and costs in the North Thames Dialysis Study of elderly people on dialysis: a prospective cohort study

BACKGROUND Evidence-based health policy is urgently needed to meet the increasing demand for health services among elderly people, particularly for expensive technologies such as renal-replacement therapy. Age has been used to ration dialysis, although not always explicitly, despite the lack of rigorous empirical evidence about how elderly people fare on dialysis. We undertook a comprehensive assessment of outcomes in patients 70 years or over. METHODS We did a 12-month prospective cohort study of outcomes in 221 patients with end-stage renal failure aged 70 years or over recruited from four hospital-based renal units. We assessed 1-year survival in 125 incident patients (70-86 years) and disease burden (hospital admissions, quality of life, costs) in 174 prevalent patients (70-93 years). FINDINGS 1-year survival rates were: 71% overall; 80%, 69%, and 54% in patients 70-74 years, 75-79 years, and 80 years and older, respectively (p=0.008); and 88%, 71%, and 64% in patients with no, one, or two or more comorbid conditions, respectively (p=0.056). Cox regression analyses showed that mortality was significantly associated with age 80 years and older (relative risk 2.79 [95% CI 1.28-6.93]) and peripheral vascular disease (2.83 [1.29-6.17]), but not with diabetes, ischaemic heart disease, cerebrovascular disease, chronic obstructive airways disease, sex, or treatment method. In terms of disease burden, hospital admissions represent a low proportion of costs and was not required by a third of patients, mental quality of life in elderly dialysis patients was similar to that of elderly people in the general population, and the average annual cost per patient of 20802 (US

Amino acid clearances and daily losses in patients with acute renal failure treated by continuous arteriovenous hemodialysis

31200) (68% dialysis treatment, 1% transport, 19% inpatient hospital admissions, 12% medications) was within the range of other life-extending interventions. INTERPRETATION Our results suggest that age alone should not be used as a barrier to referral and treatment and emphasise the need to consider the benefits of dialysis in elderly people. Indicators of the ability to benefit from treatment, rather than chronological age, should be used to develop policies that ensure equal access to care for all.

Does cyclosporin increase lipoprotein(a) concentrations in renal transplant recipients

ObjectiveTo determine daily amino acid and total protein losses in patients with acute renal failure receiving total parenteral nutrition (TPN) during treatment by continuous arteriovenous hemofiltration with hemodialysis (CAVHD). DesignProspective, nonrandomized study. SettingPatients in the ICU of a regional nephrology referral center. PatientsEight clearance studies of individual amino acids were performed in six patients with acute renal failure receiving TPN. Daily nitrogen intake was 9 g (one patient), 14 g (two patients), and 18 g (three patients). The clearances of individual amino acids were measured at two dialysis flow rates to calculate daily amino acid and total protein losses. ResultsAmino acid clearance rates ranged from 7.8 ±PT 2.2 (glutamic acid) to 25.2 ±PT 4.8 mL/min (3-methylhistidine) at a dialysate flow rate of 1L/hr and from 13.6 ±PT 1.7 (tryptophan) to 33.7 ±PT 4.3 mL/min (3-methylhistidine) at a dialysate flow rate of 2 L/hr. These results represent daily amino acid losses of 1.5 ±PT 0.4% (glutamic acid) to 111.6 ±PT 16.6% (tyrosine) of the nutritional input at a dialysate flow rate of 1 L/hr and 2.1 ±PT 0.6% (glutamic acid) to 145.8 ±PT 17.8% (tyrosine) at a dialysate flow rate of 2 L/hr. Total losses would represent 8.9 ±PT 1.2% and 12.1 ±PT 2.2%, respectively, of the daily protein input. ConclusionsThese studies confirm that amino acid clearances are relatively high during CAVHD and daily losses should therefore be considered.

Continuous arteriovenous haemodialysis in critically ill patients.

Cyclosporin, the immunosuppressant of choice for renal transplant recipients, has been implicated as the cause of abnormalities in serum lipid concentrations in these patients. We have measured serum lipoprotein(a) concentrations and analysed the distribution of apoprotein(a) isoforms in 90 renal transplant recipients receiving cyclosporin and prednisolone (with or without azathioprine), 59 patients receiving azathioprine and prednisolone alone, and 146 non-hyperlipidaemic controls. Cyclosporin-treated patients had significantly higher lipoprotein(a) concentrations (median 170 [interquartile range 55-382] mg/L) than those receiving azathioprine and prednisolone (64 [10-204] mg/L, p = 0.001) or the healthy controls (94 [18-280] mg/L, p = 0.008). The difference between the azathioprine and prednisolone group and the controls was not significant. Although the time since transplantation was significantly shorter for the cyclosporin-treated group, there was no correlation between lipoprotein(a) concentration and time since transplantation (r = -0.13, p = 0.18). Apoprotein(a) phenotyping showed no significant differences in the distribution of apoprotein(a) isoforms between the treatment groups or between patient and control groups. Lipoprotein(a) concentrations are higher in renal transplant recipients treated with cyclosporin than in those maintained on azathioprine and prednisolone. The mechanisms underlying this abnormality remain to be elucidated.

Prevalence of intermittent claudication and risk factors for its development in patients on renal replacement therapy

Continuous arteriovenous haemodialysis (CAVHD) is a new treatment for critically ill patients with renal failure that combines convective and diffusive solute removal. The clearance of urea (14.8-22.1 ml/min) is sufficient to achieve a steady-state urea concentration of 22 mmol/l, even in patients with a high catabolic rate and cardiovascular instability. The technique is simple and does not involve the use of blood pumps or specialised staff. Initial experience in 36 critically ill patients with renal failure indicates that it is safe and reliable, with less associated morbidity than other techniques.

The effects of amlodipine and enalapril on renal function in adults with hypertension and nondiabetic nephropathies: A 3-year, randomized, multicenter, double-blind, placebo-controlled study

The prevalence of symptomatic intermittent claudication (IC) was assessed using a standard cardiovascular questionnaire in a cohort of 325 patients on renal replacement therapy (RRT). IC was found in 19% of patients, 77% of whom were smokers and 22% diabetic. It was more common in men than women and in smokers than non-smokers (p < 0.001). Those with IC were significantly older (61 years vs. 50 years p < 0.001), smoked more (23 pack years vs. 12 pack years p = 0.002), had higher median systolic blood pressures (143 mmHg vs. 140 mmHg p = 0.041) and median triglyceride levels (2.07 mmol/l vs. 1.60 mmol/l p = 0.023) than those renal patients without IC. A case control study matching for age, sex and treatment revealed patients with IC to have higher median systolic blood pressure (147 mmHg vs. 140 mmHg p = 0.031), cholesterol (6.70 mmol/l vs. 5.90 mmol/l p = 0.029), LDL cholesterol (4.64 mmol/l vs. 3.86 mmol/l p = 0.011), and contained a greater proportion of smokers (78% vs. 50% p < 0.001). IC is common in patients on RRT. Whilst smoking was prevalent among those with IC it was much less frequent than in the general population with IC. Other factors such as hypertension, lipid abnormalities or the uraemic state itself may also be important in the development of IC in these patients.

What Are Common Management Errors in Chronic Peritoneal Dialysis

BACKGROUND Placebo-controlled trials have found that angiotensin-converting enzyme inhibitors (ACEIs) decrease proteinuria and slow the progression of nondiabetic nephropathies. However, head-to-head comparisons of ACEIs and calcium channel blockers (CCBs) have shown conflicting results. Indeed, a recent metaanalysis concluded that there is still uncertainty about the greater renoprotection seen with ACEIs or angiotensin II receptor blockers in nondiabetic patients with renal disease, particularly when using true glomerular filtration rate (GFR) as the primary outcome. OBJECTIVE The objective of this 3-year, randomized, multicenter, double-blind, placebo-controlled study was to compare true GFR decline (measured by yearly 51Cr-EDTA blood clearance) in nondiabetic, nonnephrotic adult hypertensive patients with estimated creatinine clearance of 20 to 60 mL/min.1.73 m(2), when randomized to a CCB (amlodipine, 5-10 mg/d) or an ACEI (enalapril, 5-20 mg/d). METHODS Patients (aged 18-80 years) entered a 4-week placebo run-in washout period and previous antihypertensive drugs were tapered off over 2 weeks. Add-on treatments were atenolol (50-100 mg/d), loop diuretics (furosemide, 20-500 mg/d or torsemide, 5-200 mg/d), alpha-blockers (prazosin, 2.5-5 mg/d or doxazosin, 1-16 mg/d), and centrally acting drugs (rilmenidine, 1-2 mg/d or methyldopa, 250-500 mg/d). The primary end point was true GFR measured by yearly (51)Cr-EDTA blood clearance. Secondary end points included a clinical composite of renal events and tolerability collected by a full clinical and laboratory evaluation at each study visit. Post hoc analyses for the change in GFR, proteinuria, and time to clinical events were also planned on baseline proteinuria subgroups (<1 and >or=1 g/d) before unblinding the database. RESULTS Three hundred eighteen patients entered the run-in period and 263 patients (156 men/107 women; mean age, 58 years) were randomized to receive either amlodipine (5 mg/d, n=132) or enalapril (5 mg/d, n=131). Blood pressure declined from 165/102 mm Hg to 138/84 mm Hg and 138/85 mm Hg with amlodipine and enalapril, respectively (no between-group significance). Only 20.8% of the patients randomized to ACEI treatment received diuretics at the last observation. No statistically significant difference was found between amlodipine and enalapril in GFR decline (-4.92 and -3.98 mL/min.1.73 m(2), respectively, at last observation) and composite secondary end point after a median follow-up of 2.9 years, including in the subgroup of patients with proteinuria >1 g/d at baseline. Protein excretion rate decreased significantly from baseline in patients taking enalapril plus diuretics (median -270 mg/d; P<0.001) but not in patients taking amlodipine plus diuretics (-25 mg/d at last observation). CONCLUSION In this cohort of nondiabetic, nonnephrotic hypertensive patients, no statistically significant difference in true GFR decline was found over 3 years between amlodipine-treated patients and enalapril-treated patients with main add-on treatment with ss-blockers, including in the subgroup of patients with proteinuria >1 g/d.

Peritoneal Dialysis Catheter Removal for Acute Peritonitis: A Retrospective Analysis of Factors Associated With Catheter Removal and Prolonged Postoperative Hospitalization

How well does the D/Pcr correlate with drain volume? The correlation coefficient between net ultrafiltration and D/Pcr was 0.59 in a recent report on peritoneal equilibration tests in 100 new and problem-free peritoneal dialysis patients. The report indicated that drain volume could vary by about 600 ml for any given DlPcr and still fall within the 95% confidence limits. Unpublished data from London, Ontario, show an even lower correlation coefficient ( 0.25; P. Blake, personal communication). One might argue that the D/Do glucose is the appropriate parameter to examine since it is glucose, not creatinine, that is responsible for the osmotic gradient inducing ultrafiltration. However, Twardowsi’s original data show that the D/Do glucose was also rather poor in predicting drain volume with a correlation coefficient of 0.43 (Fig. 1). Thus, clinicians should recognize that PETderived solute transport data, while statistically related to drain volume, do so in a much less predictable fashion than is generally thought. Therefore, the finding that a patient is in a different PET category for solute transport and drain volume is consistent with reported data. In addition, one should not make assumptions regarding solute transport based upon observed drain volumes.