Extreme NT-proBNP often signals infection

Extremely high NT-proBNP in hospitalized adults more often accompanied infection than primary heart failure.
*Retrospective cohort study; Level 3 (OCEBM).

Citation

Abu Suleiman A, Bhatty A, Mitchell CD, Desborough R, Clark AL. Extremely High NT-proBNP in Unselected Hospital Admissions. Journal of General Internal Medicine. 2026.

Background

NT-proBNP is commonly used to help rule out heart failure, but high values can occur with kidney disease, older age, abnormal heart rhythms, and severe infection. This study examined what diagnoses and outcomes followed extremely high values in real-world hospital admissions.

Patients

415 adult hospital admissions in the United Kingdom with NT-proBNP ≥20,000 pg/mL. Outpatient results were excluded; repeat tests during the same admission were not counted separately.

Intervention

No treatment intervention; exposure was extremely high NT-proBNP.

Control

Comparisons included survivors versus non-survivors and infection as primary diagnosis versus other diagnoses.

Outcome

Primary diagnoses, imaging findings, all-cause mortality, and predictors of mortality.

Follow-up Period

Median 598 days among survivors; 6-month mortality reported.

Results

FindingResult
Primary diagnosis: infection59.5%
Primary diagnosis: heart failure19%
In-hospital mortality43.6%
6-month mortality64.5%
Older age and mortalityHR 1.02 per year (95% CI 1.01 to 1.03)
Higher albumin and mortalityHR 0.96 (95% CI 0.94 to 0.98)
Chronic kidney disease and mortalityHR 0.73 (95% CI 0.58 to 0.92)
Hypertension and mortalityHR 0.75 (95% CI 0.60 to 0.94)

NT-proBNP: N-terminal pro–B-type natriuretic peptide; HR: hazard ratio.

Results used complete-case multivariable analysis. The control was not a treatment group. No minimally important difference applies.

Limitations

Single-center retrospective design limits generalizability and cannot prove cause. Diagnoses depended on documentation. Some frailty, lactate, heart ultrasound, and post-discharge cause-of-death data were missing. The assay capped values at 35,000 pg/mL.

Funding

No financial support; no declared competing interests.

Clinical Application

Do not diagnose heart failure from extreme NT-proBNP alone; actively evaluate for infection or sepsis alongside cardiac assessment.