Elevated resting heart rate is an independent predictor of all-cause death and cardiovascular events in Japanese ambulatory hemodialysis patients.

BACKGROUND: Elevated heart rate (HR) is an independent risk factor for all-cause death or cardiovascular events in non-hemodialysis subjects; however, the clinical significance of elevated HR in hemodialysis patients is not well studied. METHODS: We prospectively evaluated the relationship between HR and adverse outcome in a total of 229 ambulatory hemodialysis patients (57 % men; mean age 62.2 years) recruited from two dialysis clinics in 2009. Mean (SD) HR of this cohort was 74.1 (11.0) beats per minute (bpm). RESULTS: Receiver operating characteristic curves identified an HR cut-off level of ≥80 bpm for increased adverse outcome. After a mean follow-up of 525 days (range 7-760 days) a total of 30 primary endpoints (21 all-cause deaths, 4 acute coronary syndromes and 8 strokes) and 38 secondary endpoints (30 primary endpoints, 8 congestive heart failures, and 5 other cardiovascular events) were detected. Cox regression analysis revealed that HR >80 bpm was not an independent predictor of primary endpoints [hazard ratio 1.81, 95 % confidence interval (CI) 0.79-4.11, p = NS], but of secondary endpoints (hazard ratio 2.01, 95 % CI 1.01-4.22, p < 0.05) after adjusting for age, sex, hemodialysis duration, and cardiovascular risks. CONCLUSIONS: Elevated HR is an independent predictor of all-cause death and cardiovascular events in Japanese ambulatory hemodialysis patients.

Plasma aldosterone in hypertensive patients on chronic hemodialysis: distribution, determinants and impact on survival.

A high plasma aldosterone concentration (PAC) is known to be associated with poor outcome in patients with cardiac disease. However, the prognostic value of PAC in chronic hemodialysis (HD) patients is unknown. In 1996 we examined 128 hypertensive patients treated with antihypertensive drugs, excluding angiotensin-converting enzyme inhibitors, who were undergoing chronic HD (ages 61.8+/-13.8 years, 62% male), and for whom PAC (ng/dl) data were obtained. We followed up these patients until November 2003. During the follow-up period, 30 patients died. About half of all patients (48%) had PAC values above the normal range. We assigned the 128 patients to a lower (<22.9) or higher (> or = 22.9) PAC group according to the median baseline PAC. The survival rate as calculated by the Kaplan-Meier method was 90.6% in the higher PAC group and 62.5% in the lower PAC group (p=0.003). In multivariate analysis, serum potassium and plasma renin activity were independent determinants of PAC. Cox proportional hazards analysis, with adjustment for other variables including diabetes, showed that lower PAC was independently predictive of death. The adjusted hazard ratio (95% confidence interval) of the lower PAC group was 2.905 (1.187-7.112, p=0.020). The significance of PAC became marginal by adjustment with albumin or potassium. These results indicate that higher PAC is common, but not associated with an increase in total and cardiovascular deaths among hypertensive patients undergoing chronic HD. The association between lower PAC and poor survival may be driven by volume retention and/or lower potassium.

Outcome study of renal biopsy patients in Okinawa, Japan.

Here we report a community-based epidemiologic study of patients who received renal biopsy in Okinawa, Japan between 1967 and 1994. The total number of cases was 2832 (1395 men and 1437 women), and the mean (SD) age at biopsy was 30.0 (10.0) years (range 1.0 to 88.0 years). The most common clinical indications for renal biopsy were proteinuria/hematuria (46.7%), nephrotic syndrome (21.2%), acute glomerulonephritis (10.1%), and systemic lupus erythematosus (7.5%). Patients who received renal biopsy between 1985 and 1994 (N= 1480) were much less likely to have acute glomerulonephritis than patients treated between 1967 and 1984 (N= 1352); the rates of proteinuria/hematuria, renal failure, and diabetes mellitus were slightly higher in the later period. Okinawa patients who began dialysis between 1971 and 2000 (N= 5246) were also studied. Among them, a total of 468 patients (260 men and 208 women) began dialysis after renal biopsy. The cumulative incidence of end-stage renal disease (ESRD) among these patients was 17% in 17 years. Half of these patients developed ESRD in the 5.8 years after renal biopsy. Among the dialysis patients, the biopsy rate was 12.6% in chronic glomerulonephritis, 1.7% in diabetes mellitus, 2.6% in nephrosclerosis, and 52.1% in systemic lupus erythematosus. The diagnoses of primary renal diseases were primarily made clinically. The survival rate after starting dialysis therapy was slightly better in those with than in those without renal biopsy but this finding was not statistically significant (adjusted hazards ratio 0.855, 95% CI 0.711-1.028, P= 0.095). The clinical significance of renal biopsy, other than its provision of histologic evidence, remains to be shown.