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R Stuart C Rodger

Publications and source records attributed to R Stuart C Rodger.

7 recordsLinked to original sources

Diagnostic potential of circulating natriuretic peptides in chronic kidney disease.

BACKGROUND: Measurement of natriuretic peptides, particularly brain natriuretic peptide (BNP) is an established method for the diagnosis of cardiovascular disorders, chiefly left ventricular (LV) dysfunction. The influence of renal function on the diagnostic utility of natriuretic peptides is unclear. METHODS: We performed a cross-sectional study of 296 patients with renal disease but no history of cardiac disease using echocardiography to assess LV mass and function. Circulating levels of atrial natriuretic peptide (ANP) and BNP were also measured. RESULTS: The incidence of LV hypertrophy increased with progressive renal dysfunction; from 39% in patients with near-normal renal function, to 80% in renal transplant patients. There was a negative correlation between both ANP and BNP, and glomerular filtration rate (GFR) (ANP: r = -0.28, P<0.001; BNP: r = -0.40, P<0.001). Serum ANP and BNP had sensitivity and specificity for LV hypertrophy of 39.9%, 87.4% (ANP) and 61.4%, 67.6% (BNP) respectively. Sensitivity and specificity for LV dysfunction was 77.2%, 32.4% (ANP) and 71.8%, 40.0% (BNP). Significant confounders in determining serum ANP were haemoglobin, beta blockade and albumin, while serum BNP levels were significantly confounded by GFR, albumin, haemoglobin, beta blockade and age. CONCLUSIONS: Across a spectrum of renal dysfunction, GFR is a more important determinant of serum BNP than ventricular function, and several factors are predictors of natriuretic peptide levels. In chronic kidney disease, the use of natriuretic peptides to diagnose LV hypertrophy must be interpreted in light of these other factors. The use of these peptides in renal dysfunction to diagnose LV dysfunction may be of limited value.

Adult↗

A prospective open-label randomised trial of quinapril and/or amlodipine in progressive non-diabetic renal failure.

BACKGROUND: Treatment of hypertension slows the progression of non-diabetic nephropathies, but the optimal regimen is unknown. Angiotensin-converting enzyme inhibitors are more effective than beta-blockers, but their merits relative to calcium channel blockers are less clear. METHODS: 73 hypertensive patients with progressive non-diabetic nephropathies were prospectively randomised to open-label quinapril (Q, n = 28), amlodipine (A, n = 28) or both drugs (Q&A, n = 17). Therapy was increased to achieve a diastolic blood pressure < 90 mm Hg. Patients were followed for 4 years or until death. The primary outcome was the combined endpoint of doubling serum creatinine, starting renal replacement therapy or death. RESULTS: There was no significant difference in the primary outcome, or in the change of glomerular filtration rate. Blood pressure was equally controlled throughout the study period. 29 (40%) patients were withdrawn from the allocated therapy (Q 39%, A 36%, Q&A 47%). Because of the large crossover between trial arms, the data were re-analysed per protocol. The effect on preventing the need for renal replacement therapy then approached significance between the groups (p = 0.089) and the combined quinapril-containing groups were less likely than the amlodipine group to achieve the primary endpoint (p = 0.038), or the individual endpoints of renal replacement therapy (p = 0.030) or doubling creatinine (p = 0.051). CONCLUSIONS: Quinapril is more effective than amlodipine at reducing the incidence of dialysis in patients with progressive renal failure, but only if they can tolerate the drug. The tolerability of these drugs in patients with advanced renal failure is poor.

Adult↗

Allocation of deceased donor kidneys for transplantation: opinions of patients with CKD.

BACKGROUND: Deceased donor kidney allocation schemes are designed to balance optimal utility with equity of access. The aim of this single-center survey is to seek patient opinion about the relative importance of factors used to determine the optimal transplant recipient in kidney allocation schemes. METHODS: In each of 8 scenarios, participants were invited to select which 1 of 2 hypothetical patients should receive a kidney. RESULTS: Two hundred thirty-two of 295 invited patients (78.6%) completed the questionnaire: 104 of 153 invited hemodialysis patients (68.0%) and 128 of 142 invited patients with functioning transplants (90.1%). Only 6.0% of participants agreed with current UK Transplant (UKT) and United Network for Organ Sharing (UNOS) allocation to a patient not yet on dialysis therapy who had been on the transplant waiting list longer than a patient already on dialysis therapy. Only 24.6% of participants agreed with the UKT and UNOS schemes that the transplant survival advantage associated with HLA matching warranted allocation of a kidney to a patient who had been waiting 2 years in preference to a patient waiting 7 years. Participants also were opposed to the use of recipient age and balance of exchange agreements (that reward centers with high rates of organ retrieval). The majority agreed with UKT and UNOS that recipient sex should not be used to allocate kidneys and allocation should favor recipients who have waited longer. CONCLUSION: Patients disagreed with several aspects of current allocation systems. Analysis of patient opinion should be taken into consideration when attempting to optimize the use of this scarce health resource.

Adolescent↗

Persistent dipstick haematuria following renal transplantation.

Despite widespread testing for dipstick haematuria following renal transplantation, there are no published series describing the prevalence and possible causes of this complication in an adult population. A cross-sectional study of 640 renal transplant recipients under review at our follow-up clinic was performed. Persistent haematuria was defined as a minimum of 1+ of blood on urinalysis stick testing detected at not fewer than 75% of clinic visits since its onset, or since the start of routine testing, present over a period of at least 4 weeks. The prevalence of persistent dipstick haematuria was 13.3%. Median serum creatinine was higher in patients with persistent haematuria but age, gender and length of time since transplantation were not significantly different. Potential explanations for persistent haematuria in 21 of 85 affected patients were chronic infection, ureteric stent without chronic infection, regular or intermittent self-catheterization, persistent menstrual bleeding, anticoagulant therapy, graft calculus, and allograft renal cell carcinoma. Recurrent or de novo glomerular disease was confirmed by graft biopsy in 10 of 85 patients. Among the 41 recipients whose original cause of renal failure was IgA nephropathy (IgAN), the prevalence of persistent haematuria was 31.7% compared with 12% in the remaining patients (relative risk 2.6, 95% CI: 1.6-4.3). Persistent haematuria in IgAN patients was not associated with gender, age or time since transplantation. After 29 months of follow-up, 20% of patients with haematuria had progressed to graft failure or death compared with 11.6% of the unaffected group (p = 0.029). However, despite the association with earlier graft failure, haematuria did not predict this endpoint independently of renal function.

Adolescent↗

Determinants of hypertension and left ventricular function in end stage renal failure: a pilot study using cardiovascular magnetic resonance imaging.

Cardiovascular disease is the principal cause of mortality in patients with renal failure. Left ventricular (LV) abnormalities are adverse prognostic indicators for cardiovascular outcome. The aim of this study was to use cardiac magnetic resonance scanning (CMR) to define LV functional abnormalities in haemodialysis (HD) patients and clarify the determinants of blood pressure (BP) and the effect of anaemia in this population. We studied 44 HD patients and 11 controls with CMR performed following dialysis. Forty patients and 11 controls completed the study. LV mass (P<0.001) and estimated systemic vascular resistance (SVR) (P = 0.002) were significantly higher in the dialysis group compared to controls. LV ejection fraction (P = 0.002) and SV (P = 0.043) were lower than controls. In the HD patients, BP correlated significantly with cardiac output (CO; r = 0.569, P<0.001) and end diastolic volume (EDV; r = 0.565, P<0.001) but there was no correlation between BP and SVR (r = 0.201, P = 0.594). Haemoglobin was inversely correlated with both CO (r = -0.531, P<0.001) and EDV (r = -0.493, P = 0.001) and positively with SVR (r = 0.402, P = 0.009). HD patients had a higher LV mass and lower ejection fraction than controls. The relationship of BP with CO, but not SVR, supports the theory that a major determinant of BP is intravascular volume and CO rather than vascular resistance although there was a fixed increase in SVR in this population. Improved understanding of the mechanisms underlying increased SVR and improved control of CO and intravascular volume may allow better therapeutic strategies. CMR provides insights into the pathophysiology of hypertension and LV dysfunction in HD patients.

Adult↗