The LENT index predicts 30 day outcomes following hospitalization for heart failure

Abstract

Aims: The LE index (Length of hospitalization plus number of Emergent visits ≤6 months) predicts 30 day all-cause readmission or death following hospitalization for heart failure (HF). We combined N-terminal pro-B type natriuretic peptide (NT-proBNP) levels with the LE index to derive and validate the LENT index for risk prediction at the point of care on the day of hospital discharge.

Methods and results: In this prospective cohort sub-study of the Patient-centred Care Transitions in HF clinical trial, we used log-binomial regression models with LE index and either admission or discharge NT-proBNP as the predictors and 30 day composite all-cause readmission or death as the primary outcome. No other variables were added to the model. We used regression coefficients to derive the LENT index and bootstrapping analysis for internal validation. There were 772 patients (mean [SD] age 77.0 [12.4] years, 49.9% female). Each increment in the LE index was associated with a 25% increased risk of the primary outcome (RR 1.25, 95% CI 1.16-1.35; C-statistic 0.63). Adjusted for the LE index, every 10-fold increase in admission and discharge NT-proBNP was associated with a 48% (RR 1.48; 95% CI 1.10, 1.99; C-statistic 0.64; net reclassification index [NRI] 0.19) and 56% (RR 1.56; 95% CI 1.08, 2.25; C-statistic 0.64; NRI 0.21) increased risk of the primary outcome, respectively. The predicted probability of the primary outcome increased to a similar extent with incremental LENT, regardless of whether admission or discharge NT-proBNP level was used.

Conclusions: The point-of-care LENT index predicts 30 day composite all-cause readmission or death among patients hospitalized with HF, with improved risk reclassification compared with the LE index. The performance of this simple, 3-variable index - without adjustment for comorbidities - is comparable to complex risk prediction models in HF.

Trial registration: ClinicalTrials.gov NCT02112227.

Keywords: Heart failure; Hospitalization; Risk prediction.

Conflict of interest statement

Dr. Van Spall has received an educational grant from Roche Diagnostics and is supported by a career award from Hamilton Health Sciences and McMaster University. Dr. Januzzi has received consulting income from Roche Diagnostics and has received research funding from Abbott Diagnostics and Novartis Pharmaceuticals. Dr. Ko is supported by a Clinician Scientist Award from the Heart and Stroke Foundation of Canada. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.

©2020 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

Figures

FIGURE 1

Flow diagram of the study participants. Of a total of 2494 patients in the PACT‐HF trial, 772 with NT‐proBNP measured at admission or discharge were included in the sub‐study. NT‐proBNP was measured with a point‐of‐care device whose upper limit of detection was 9000 pg/mL.

FIGURE 2

The distribution of LENT index scores in the cohort of patients hospitalized for HF. The distribution of admission and discharge LENT scores was similar.

FIGURE 3

The predicted probability of 30 day composite all‐cause readmission or death in patients hospitalized for HF. The LENT indices demonstrate a continuum of risk, with higher scores associated with an increased risk of 30 day composite all‐cause readmission or death.

FIGURE 4

The predicted probability of 30 day all‐cause readmission in patients hospitalized for HF. The LENT indices demonstrate a continuum of risk, with higher scores associated with an increased risk of 30 day all‐cause readmission.

FIGURE 5

The LENT risk index and its performance in an internally validated sample.