The incremental prognostic and clinical value of multiple novel biomarkers in heart failure.

AIMS: In recent years there has been an increase in the number of biomarkers in heart failure (HF). The clinical role for these novel biomarkers in combination is not clear. METHODS AND RESULTS: The following novel biomarkers were measured from 628 patients recently hospitalized with decompensated HF; mid-regional pro-adrenomedullin (MR-proADM), mid-regional pro-atrial natriuretic peptide (MR-proANP), copeptin, high-sensitivity cardiac troponin T (hs-cTnT), ST2, galectin-3, cystatin C, combined free light chains (cFLC) and high sensitivity C-reactive protein (hsCRP). The incremental prognostic value of these novel biomarkers was evaluated within an extensive model containing established predictors of mortality. During a mean (SD) follow-up of 3.2 (1.5) years, 290 (46%) patients died. Elevated concentrations of all novel biomarkers were associated with an increased unadjusted risk of mortality but only two-thirds were independent predictors following multivariable analysis. Using dichotomized cut-points from receiver operating characteristic analysis, MR-proADM, hs-cTnT, cFLC, hsCRP, and ST2 remained independent predictors of mortality. Further dichotomization into low (0-2 elevated biomarkers) or high (at least three of the five biomarkers elevated) risk groups provided greatest incremental prognostic value (hazard ratio 2.20, 95% confidence interval 1.37-3.54; P = 0.001) and improved the performance of the model (C-statistic 0.730 from 0.721, net reclassification index 32.5%). CONCLUSION: The novel biomarkers included in this study added little, if any, incremental prognostic value on their own to a model containing established predictors of mortality. However, following dichotomization, five of the novel biomarkers provided incremental prognostic value. There was a clear gradient in the risk of death with increasing numbers of elevated novel biomarkers, with the presence of at least three identifying patients at greatest risk of mortality.

Combined Free Light Chains Are Novel Predictors of Prognosis in Heart Failure.

OBJECTIVES: This study investigated the prevalence and potential incremental prognostic value of combined free light chains (cFLCs) in patients recently hospitalized with decompensated heart failure (HF). BACKGROUND: Inflammatory pathways are recognized in the pathogenesis and progression of HF. Free light chain (FLC) elevation is conventionally associated with monoclonal gammopathies, including multiple myeloma. Polyclonal increases in both kappa and lambda FLCs occur in autoimmune and other chronic inflammatory conditions. Recently, a novel assay for measuring kappa and lambda immunoglobulin FLCs together, known as combined free light chain (cFLC) has been developed. METHODS: Six hundred twenty-eight patients recently hospitalized with decompensated HF were studied. cFLCs were measured by turbidimetry using an immunoassay. The incremental prognostic value of cFLCs for mortality was evaluated using Cox proportional hazard models including 22 established predictors of outcome in HF. RESULTS: Of 628 patients, 290 (46%) died during a follow-up of 3.2 ± 1.5 years. Two hundred seventy patients (43%) had elevated cFLCs. There was a clear gradient in the risk of death according to cFLC quartile, with those in the top quartile having an unadjusted risk of mortality more than twice that of those in the lowest quartile (hazard ratio: 2.38; p < 0.0001). After multivariable analysis, cFLC remained an independent predictor of mortality, with an almost 50% higher adjusted risk for those in the top compared with bottom quartile. Older age, lower body mass index, New York Heart Association classification III/IV, previous myocardial infarction, current smoking and B-type natriuretic peptide, bilirubin, high-sensitivity C-reactive protein, glycated hemoglobin, and lymphocyte concentrations were also independent predictors of mortality. CONCLUSIONS: cFLCs are an independent predictor of mortality in patients recently hospitalized with decompensated HF. Further work is required to assess the effects of HF therapies on cFLC concentrations and whether or not directly targeting this marker of inflammation improves prognosis for patients with HF.