Evaluation of the Incremental Prognostic Utility of Increasingly Complex Testing in Chronic Heart FailureCLINICAL PERSPECTIVE
Résumé
BACKGROUND:
Current heart failure (HF) risk prediction models do not consider how individual patient assessments occur in incremental steps; furthermore, each additional diagnostic evaluation may add cost, complexity, and potential morbidity.
METHODS AND RESULTS:
Using a cohort of well-treated ambulatory HF patients with reduced ejection fraction who had complete clinical, laboratory, health-related quality of life, imaging, and exercise testing data, we estimated incremental prognostic information provided by 5 assessment categories, performing an additional analysis on those with available N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. We compared the incremental value of each additional assessment (quality of life screen, laboratory testing, echocardiography, and exercise testing) to baseline clinical assessment for predicting clinical outcomes (all-cause mortality, all-cause mortality/hospitalization, and cardiovascular death/HF hospitalizations), gauging incremental improvements in prognostic ability with more information using area under the curve and reclassification improvement (net reclassification index), with and without NT-proBNP availability. Of 2331 participants, 1631 patients had complete clinical data; of these, 1023 had baseline NT-proBNP. For prediction of all-cause mortality, models with incremental assessments sans NT-proBNP showed improvements in C-indices (0.72 [clinical model alone]-0.77 [complete model]). Compared with baseline clinical assessment alone, net reclassification index improved from 0.035 (w/laboratory data) to 0.085 (complete model). These improvements were significantly attenuated for models in the subset with measured NT-proBNP data (c-indices: 0.80 [w/laboratory data]-0.81 [full model]); net reclassification index improvements were similarly marginal (0.091→0.096); prediction of other clinical outcomes had similar findings.
CONCLUSIONS:
In chronic HF patients with reduced ejection fraction, the marginal benefit of complex prognostic evaluations should be weighed against potential patient discomfort and cost escalation.
CLINICAL TRIAL REGISTRATION:
URL: http://www.clinicaltrials.gov. Unique identifier: NCT00047437.