What are normal proBNP (pro-brain natriuretic peptide) values?

Normal NT-proBNP (Pro-BNP) Values

Normal NT-proBNP values to exclude chronic heart failure are <125 pg/mL, and to exclude acute heart failure are <300 pg/mL, though these thresholds must be adjusted based on age, sex, obesity, race, atrial fibrillation, and renal function. 1

Standard Reference Ranges for Excluding Heart Failure

For chronic heart failure exclusion:

• NT-proBNP <125 pg/mL effectively rules out chronic heart failure 2, 1
• BNP <35 pg/mL excludes chronic heart failure 2, 1

For acute heart failure exclusion:

• NT-proBNP <300 pg/mL has 99% negative predictive value for acute heart failure 1, 3
• BNP <100 pg/mL excludes acute heart failure 2

Age-Adjusted Reference Ranges

Age significantly affects NT-proBNP levels, requiring threshold adjustments in older adults 1:

Age-specific upper reference limits (97.5th percentile):

• Age <50 years: NT-proBNP 0-450 pg/mL 3
• Age 50-75 years: NT-proBNP 0-900 pg/mL 3
• Age >75 years: NT-proBNP 0-1,800 pg/mL 2, 3

The median NT-proBNP in healthy adults aged 85+ is approximately 297-351 pg/mL, with upper reference values reaching 519-649 pg/mL in women and men respectively 4. Recent population-based studies show that 37-39% of apparently healthy older adults have NT-proBNP >125 pg/mL, indicating the standard cutoff performs poorly in this age group 5.

Critical Adjustments for Special Populations

Obesity (BMI ≥30 kg/m²):

• Lower thresholds by 20-30% for both NT-proBNP and BNP 2, 1
• Obesity paradoxically decreases natriuretic peptide levels despite increased cardiovascular risk 2, 1

Black patients:

• Lower thresholds by 20-30% to avoid false-negative results 2, 1
• Black individuals typically have 20-30% lower baseline values 1

Atrial fibrillation:

• Increase thresholds by 20-30% for both peptides 2, 1
• Atrial fibrillation independently elevates natriuretic peptide levels 1

Elderly patients (>75 years):

• Raise thresholds by 20-30% 2
• Age-related decreases in left ventricular compliance and renal function elevate baseline levels 2

Chronic kidney disease:

• For eGFR <60 mL/min/1.73m², use NT-proBNP cutoff of 1,200 pg/mL instead of 300 pg/mL 2, 1
• Exclude patients on renal replacement therapy from standard natriuretic peptide interpretation 2

Neprilysin inhibitor therapy (sacubitril/valsartan):

• Use NT-proBNP only for monitoring; BNP measurements are unreliable due to neprilysin inhibition 2, 1
• NT-proBNP requires no adjustment with these medications 2, 1

Sex Differences

Women have higher baseline NT-proBNP values than men across all age groups 5, 6:

• At age <30 years: median 51 pg/mL in women vs 21 pg/mL in men 6
• At age 50-59 years: median 66 pg/mL in women vs 38 pg/mL in men 6
• 9.8% of young women (<30 years) have NT-proBNP ≥125 pg/mL compared to only 1.4% of young men 6

Common Pitfalls

The 125 pg/mL cutoff is inadequate for older adults: Population studies demonstrate that up to 39% of healthy individuals over 65 years have values exceeding this threshold, making it unsuitable for screening in elderly populations without age adjustment 5.

Obesity creates false reassurance: Obese patients may have "normal" NT-proBNP levels despite significant heart failure; clinicians must lower diagnostic thresholds by 20-30% in patients with BMI ≥30 kg/m² 2.

Renal dysfunction requires different interpretation: Standard cutoffs dramatically overdiagnose heart failure in patients with reduced eGFR; doubling the threshold to 1,200 pg/mL improves diagnostic accuracy 2, 1.