Dunlay, Shannon M.

Background— Mortality among patients with heart failure is high. Though individual biomarkers have been investigated to determine their value in mortality risk prediction, the role of a multimarker strategy requires further evaluation. Methods and Results— Olmsted County residents presenting with heart failure from July 2004 to September 2007 were recruited to undergo biomarker measurement. We investigated whether addition of C-reactive protein, B-type natriuretic peptide, and troponin T to a model including established risk indicators improved 1-year mortality risk prediction using the c statistic, integrated discrimination improvement, and net reclassification improvement. Among 593 participants, the mean age was 76.4 years, and 48% were men. After 1 year of follow-up, 122 (20.6%) participants had died. Patients with C-reactive protein (<11.8 mg/L), B-type natriuretic peptide (<350 pg/mL), and troponin T (≤0.01 ng/mL) less than the median had low 1-year mortality (3.3%), whereas those with 2 or 3 biomarkers greater than the median had markedly increased mortality (30.8% and 35.5%, respectively). The addition of 2 or more biomarkers to the model offered greater improvement in 1-year mortality risk prediction than use of a single biomarker. The combination of C-reactive protein and B-type natriuretic peptide resulted in an increase in the c statistic from 0.757 to 0.810 ( P <0.001), an integrated discrimination improvement gain of 7.1% ( P <0.001), and a net reclassification improvement of 22.1% ( P <0.001). Use of all 3 biomarkers offered no incremental gain (integrated discrimination improvement gain 0.7% versus C-reactive protein+B-type natriuretic peptide, P =0.065). Conclusions— Biomarkers improved 1-year mortality risk prediction beyond established indicators. The use of a 2-biomarker combination was superior to a single biomarker in risk prediction, though addition of a third biomarker conferred no added benefit.

Background— Tumor necrosis factor-α (TNFα), an inflammatory cytokine, was reported to be elevated in trials of heart failure (HF) with reduced ejection fraction (EF) and associated with mortality. Whether this is true for HF with preserved EF is unknown, and community data are lacking. We evaluated the distribution of TNFα, its association with baseline characteristics and mortality, and its benefit in assessing risk in community HF patients. Methods and Results— Olmsted County residents with active HF from July 2004 to March 2007 (n=486; mean age, 76.7 years; EF ≥50%, 55%) were prospectively recruited. Clinical characteristics and TNFα were measured. Elevated TNFα (more than the assay limit of normal of 2.8 pg/mL) was present in 143 (29%). Higher TNFα was associated with decreased creatinine clearance, nonsmoking status, anemia, and greater comorbidity ( P trend <0.05 for all). Mortality increased with increasing TNFα ( P =0.016), with 1-year mortality estimates of 16%, 18%, 23%, and 32% from the lowest to highest quartile, respectively. After adjustment for age, sex, and EF, the hazard ratios for death were 1.24, 1.37, and 1.90 from the second to the highest TNFα quartile, respectively ( P trend =0.007). TNFα contributed to risk assessment as indicated by increases in the area under the receiver operating characteristic curves in all models examined ( P <0.05 for all). Results did not differ by EF ( P =0.60 interaction term of TNFα and EF). Conclusions— TNFα was elevated in a large portion of community HF patients, was associated with a large decrease in survival, and provided a significant incremental increase in risk assessment above established indicators. TNFα is useful for risk assessment in HF patients with preserved and reduced EF.