Range of plasma brain natriuretic peptide (BNP) levels in hemodialysis patients at a high risk of 1-year mortality and their relationship with the nutritional status: a retrospective cohort study in one institute

Abstract

Background: Brain natriuretic peptide (BNP) levels are used as a marker of heart failure, which is the leading cause of morbidity and mortality in dialysis patients. BNP levels increase as renal function declines. The range of BNP levels associated with satisfactory longevity in dialysis patients currently remains unknown. Methods: In total, 660 patients receiving maintenance hemodialysis were enrolled. BNP levels were measured at the end of the year and in a follow-up to assess 1-year mortality between 2008 and 2012. Patients were divided into six groups according to BNP levels: < 50 (reference), 50 to < 100, 100 to < 300, 300 to < 500, 500 to < 1000, and ≥ 1000 pg/mL. One-year mortality at each BNP level was analyzed using Cox's proportional hazards model after adjustments for confounding factors.Results: During the follow-up period, 78 (11.8%) deaths were recorded. After adjustments for confounding factors, such as gender, age, hemodialysis vintage, and primary disease, the risk of 1-year mortality was significantly high with BNP levels of 500 to < 1000 (hazard ratio [HR] 3.010; 95% confidence interval [CI] 1.065-10.729; P = 0.037) and more than 1000 pg/mL (HR 5.291; 95%CI 2.014-18.170; P = 0.0003). After adjustments for Kt/V, the risk of 1-year mortality was also significantly high with BNP levels of 500 to < 1000 (HR 3.045; 95%CI 1.065-10.929; P = 0.037) and more than 1000 pg/mL (HR 5.221;; P = 0.0006). Following further adjustments for nutritional factors, such as albumin levels, total cholesterol levels, the normalized protein catabolic rate (nPCR), body mass index (BMI), and percent creatinine generation rate (%CGR), BNP levels of 500-1000 (HR 1.990; 95%CI 0.639-7.570; P = 0.244), and more than 1000 pg/mL (HR 2.100; 95%CI 0.663-8.105; P = 0.213) were no longer risk factors.

Range of serum transthyretin levels in hemodialysis patients at a high risk of 1‐year mortality: A retrospective cohort study

“…Chertow et al reported that TTR levels correlated with age, sex, diabetes, body weight, blood urea nitrogen, creatinine, albumin, phosphorus, and bicarbonate relative to TTR >40 mg/dl, and the adjusted relative risks were 2.41, 1.85, 1.49, and 1.23, for TTR levels <15, 15 to <20, 20 to <25, and 25–30 mg/dl, respectively [4]. We reported in our previous report that BNP levels showed the strongest correlation with TTR levels, and, after adjustment for TTR levels, the risk associated with high BNP levels was no longer significant [15]. Based on the above, we concluded that TTR is the strongest independent predictive factor for 1‐year mortality in hemodialysis patients.…”