International differences in dialysis mortality reflect background general population atherosclerotic cardiovascular mortality.

Existing national, racial, and ethnic differences in dialysis patient mortality rates largely are unexplained. This study aimed to test the hypothesis that mortality rates related to atherosclerotic cardiovascular disease (ASCVD) in dialysis populations (DP) and in the background general populations (GP) are correlated. In a cross-sectional, multinational study, all-cause and ASCVD mortality rates were compared between GP and DP using the most recent data from the World Health Organization mortality database (67 countries; 1,571,852,000 population) and from national renal registries (26 countries; 623,900 population). Across GP of 67 countries (14,082,146 deaths), all-cause mortality rates (median 8.88 per 1000 population; range 1.93 to 15.40) were strongly related to ASCVD mortality rates (median 3.21; range 0.53 to 8.69), with Eastern European countries clustering in the upper and Southeast and East Asian countries in the lower rate ranges. Across DP (103,432 deaths), mortality rates from all causes (median 166.20; range 54.47 to 268.80) and from ASCVD (median 63.39 per 1000 population; range 21.52 to 162.40) were higher and strongly correlated. ASCVD mortality rates in DP and in the GP were significantly correlated; the relationship became even stronger after adjustment for age (R(2) = 0.56, P < 0.0001). A substantial portion of the variability in mortality rates that were observed across DP worldwide is attributable to the variability in background ASCVD mortality rates in the respective GP. Genetic and environmental factors may underlie these differences.

The enigma of hypertensive ESRD: observations on incidence and trends in 18 European, Canadian, and Asian-Pacific populations, 1998 to 2002.

BACKGROUND: Despite improved treatment of hypertension and decreasing rates of stroke and coronary heart disease, the reported incidence of hypertensive end-stage renal disease (ESRD) increased during the 1990s. However, bias, particularly from variations in acceptance into ESRD treatment (ascertainment) and diagnosis (classification), has been a major source of error when comparing ESRD incidences or estimating trends. METHODS: Age-standardized rates were calculated in persons aged 30 to 44, 45 to 64, and 65 to 74 years for 15 countries or regions (separately for the Europid and non-Europid populations of Canada, Australia, and New Zealand), and temporal trends were estimated by means of Poisson regression. For 10 countries or regions, population-based estimates of mean systolic blood pressures and prevalences of hypertension were extracted from published sources. RESULTS: Hypertensive ESRD, comprising ESRD attributed to essential hypertension or renal artery occlusion, was least common in Finland, non-Aboriginal Australians, and non-Polynesian New Zealanders; intermediate in most European and Canadian populations; and most common in Aboriginal Australians and New Zealand Maori and Pacific Island people. Rates correlated with the incidence of all other nondiabetic ESRD, but not with diabetic ESRD or community rates of hypertension. Between 1998 and 2002, hypertensive ESRD did not increase in Northwestern Europe or non-Aboriginal Canadians, although it did so in Australia. CONCLUSION: Despite the likelihood of classification bias, the probability remains of significant variation in incidence of hypertensive ESRD within the group of Europid populations. These between-population differences are not explained by community rates of hypertension or ascertainment bias.

Preliminary experience with contrast-enhanced MR angiography in patients with end-stage renal failure.

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate our preliminary experience with routine contrast-enhanced magnetic resonance angiography (CE-MRA) of the lower limb arteries in patients with end-stage renal failure. MATERIALS AND METHODS: A retrospective analysis was performed on clinical, physiological, and imaging data for 104 patients with end-stage renal failure. Patients were considered to be in end-stage renal failure if they were on renal replacement therapy (peritoneal or hemodialysis) or were being evaluated as part of a pretransplant workup. CE-MRA was carried out on a 1.5-T scanner using a single-injection, three-station moving table technique. RESULTS: Eleven percent of asymptomatic patients with normal ankle/brachial pressure indexes (ABPI) were found to have severe arterial disease on CE-MRA, and in 30% of asymptomatic patients with abnormal ABPI, CE-MRA showed mild or no disease. Moreover two of three symptomatic patients with normal ABPI were shown to have severe disease. Two patients on peritoneal dialysis had to be switched to hemodialysis. No other adverse events were revealed. CONCLUSION: CE-MRA is a useful adjunct to clinical and physiological examination for the evaluation of the lower limb arteries in a group of patients who have a higher-than-average incidence of peripheral vascular disease, yet have previously been severely restricted from traditional angiography because of contrast-medium-induced nephrotoxicity.

Initial survival advantage of peritoneal dialysis relative to haemodialysis.

BACKGROUND: The influence of dialysis modality on prognosis is controversial. In the absence of randomized trials, epidemiological investigations present the best method for studying the problem. METHODS: 4568 haemodialysis (HD) and 2443 peritoneal dialysis (PD) records in 4921 dialysis patients treated between 1990 and 1999 were retrieved from the Danish Terminal Uremia register in order to determine the influence of dialysis form on prognosis. The register is national, comprehensive, and incident. RESULTS: Factors reducing survival included age, cardiovascular disease, malignancy, lung disease, diabetes, alcoholism, haematological disease, but not sex or hypertension. Transplant non-candidacy was associated with an adjusted relative risk of 4.7 (CI 4.0-5.6). PD mortality relative to HD (after correction for comorbidity and transplant candidacy) was 0.65 (CI 0.59-0.72, P<0.001) on an "as treated" and "history" analysis and 0.86 (CI 0.78-0.95, P<0.01) on an intention-to-treat (ITT) analysis. The difference was confined to the first 2 years of dialysis. Change in dialysis modality was associated with increased mortality, and change from PD to HD with an accelerated mortality for the first 6 months. This was presumably due to the transfer of sick PD patients, but did not explain the difference. The relative advantage of PD was lower for diabetic patients, where it was not significant on ITT analysis. Dialysis prognosis improved by 14% during the period, with similar results for HD and PD patients. PD patients who were subsequently transplanted had a significantly shorter time to onset of graft function (3.5 vs 5.1 days, P<0.05). CONCLUSIONS: These results show a survival advantage for PD during the first 2 years of dialysis treatment. This may be due to unregistered differences in comorbidity at the start of treatment, or may be causal, possibly due to better preservation of residual renal function. The study lends credence to the "integrative care" approach to uraemia, where patients are started on PD and transferred to HD when PD related mortality increases.