Serum -Trace Protein and Risk of Mortality in Incident Hemodialysis Patients

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Clinical Journal of the American Society of Nephrology (Impact Factor: 4.61). 06/2012; 7(9):1435-45. DOI: 10.2215/CJN.02240312
Source: PubMed


Residual kidney function in dialysis patients is associated with better survival, but there are no simple methods for its assessment. β-Trace protein is a novel endogenous filtration marker of kidney function that is not removed during hemodialysis and may serve as a marker for residual kidney function similar to serum creatinine in patients not on dialysis. The objective of this study was to determine the association of serum β-trace protein with mortality in incident hemodialysis patients.
Serum β-trace protein was measured in baseline samples from 503 participants of a national prospective cohort study of incident dialysis patients with enrollment during 1995-1998 and follow-up until 2004. Outcomes were all-cause and cardiovascular disease mortality analyzed using Cox regression adjusted for demographic, clinical, and treatment factors.
Serum β-trace protein levels were higher in individuals with no urine output compared with individuals with urine output (9.0±3.5 versus 7.6±3.1 mg/L; P<0.001). There were 321 deaths (159 deaths from cardiovascular disease) during follow-up (median=3.3 years). Higher β-trace protein levels were associated with higher risk of mortality. The adjusted hazard ratio and 95% confidence interval for all-cause mortality per doubling of serum β-trace protein was 1.36 (1.09-1.69). The adjusted hazard ratios (95% confidence intervals) for all-cause mortality in the middle and highest tertiles compared with the lowest tertile were 0.95 (0.69-1.32) and 1.72 (1.25-2.37). Similar results were noted for cardiovascular disease mortality.
The serum level of β-trace protein is an independent predictor of death and cardiovascular disease mortality in incident hemodialysis patients.

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Available from: Bernard G Jaar, May 11, 2014
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    • "Inhibits inducible nitric oxide synthase Negoro et al. 2002 43 J Hypertens Suppresses expression of proinflammatory mediator PAI-1 Negoro et al. 2005 46 Life Sci Suppresses expression of vascular cell adhesion molecule 1 Rossi et al. 2000 48 Nature Activation of the nuclear receptor PPARg and inhibition of NF-kB activity Endothelial injury Taba et al. 2000 42 Circ Res Steady laminar shear stress stimulates BTP expression in endothelial cells, thereby inhibiting endothelial cell apoptosis Hypertension Hirawa et al. 2002 14 Hypertension BTP overexpression protects against cardiac overload Hypertensive CKD Bhavsar et al. 2011 26 Am J Kidney Dis Plasma BTP may be useful in evaluating risk of progression of kidney disease Vasospastic angina Matsumoto et al. 2011 16 Circ J BTP elevation is associated with the degree of coronary vasoconstriction (higher arterial shear stress) Acute decompensated heart failure Manzano-Fernández et al. 2011 15 J Am Coll Cardiol BTP predicts mortality, heart failure, hospitalization, and adverse cardiovascular events (These findings also apply to the next three studies.) Hemodialysis patients Shafi et al. 2012 30 CJASN General population Astor et al. 2012 27 Am J Kidney Dis Acute coronary syndromes Manzano-Fernández et al. 2012 17 Am J Cardiol ΑP, apoptosis protein; BTP, b-trace protein; PAI-1, plasminogen activator inhibitor-1; PPARg. peroxisome proliferator-activate receptor-g. "
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