Table 1.
Baseline patient characteristics according to admission NT‐proBNP categories a
| Characteristic | Low NT‐proBNP (N = 417) | Borderline NT‐proBNP (N = 141) | High NT‐proBNP (N = 121) | P value b |
|---|---|---|---|---|
| Demographics | ||||
| Age (years) | 55 (47–64) | 73 (64–83) | 71 (61–84) | <0.001 |
| Race, N (%) | 0.085 | |||
| White | 358 (85.9) | 122 (86.5) | 112 (92.6) | |
| Black | 33 (7.9) | 11 (7.8) | 3 (2.5) | |
| Asian | 26 (6.2) | 8 (5.7) | 6 (5.0) | |
| Hispanic, N (%) | 159 (38.1) | 38 (27.0) | 32 (26.4) | 0.009 |
| Female sex | 144 (34.5) | 68 (48.2) | 51 (42.1) | 0.011 |
| Body mass index (kg/m2) | 30.0 (26.4–35.4) | 27.7 (25.4–31.0) | 27.6 (24.4–32.8) | <0.001 |
| Comorbidities, N (%) | ||||
| Hypertension | 180 (43.2) | 106 (75.2) | 96 (80.0) | <0.001 |
| Diabetes | 109 (26.1) | 49 (34.8) | 40 (33.1) | 0.084 |
| Coronary artery disease | 33 (7.9) | 30 (21.3) | 41 (34.2) | <0.001 |
| Atrial fibrillation | 11 (3.0) | 17 (14.2) | 16 (15.7) | <0.001 |
| Chronic lung disease | 25 (6.0) | 26 (18.4) | 18 (15.0) | <0.001 |
| Chronic kidney disease | 11 (2.6) | 13 (9.2) | 30 (25.0) | <0.001 |
| Asthma | 40 (9.6) | 6 (4.3) | 9 (7.5) | 0.122 |
| Immunocompromised | 26 (6.5) | 19 (14.0) | 16 (14.0) | 0.006 |
| Medication use, N (%) | ||||
| ACE inhibitor | 58 (13.9) | 28 (19.9) | 21 (17.5) | 0.193 |
| Angiotensin receptor blocker | 61 (14.6) | 28 (19.9) | 27 (22.5) | 0.076 |
| Statins | 122 (29.3) | 66 (46.8) | 63 (52.5) | <0.001 |
| Initial vital signs, N (%) | ||||
| Systolic blood pressure (mmHg) | 123 (112–139) | 129 (113–146) | 130 (108–148) | 0.103 |
| Diastolic blood pressure (mmHg) | 75 (69–82) | 71 (63–80) | 68 (62–78) | <0.001 |
| Heart rate (bpm) | 100 (89–112) | 92 (78–104) | 91 (80.5–104) | <0.001 |
| Temperature (°C) | 37.8 (37.2–38.7) | 37.7 (37.2–38.7) | 37.4 (36.9–38.25) | <0.001 |
| Respiratory rate (bpm) | 20 (18–26) | 20 (18–26) | 20 (18–28) | 0.685 |
| Oxygen saturation (%) | 93 (91–95) | 93 (91–96) | 94 (90–96) | 0.280 |
| FiO2 requirement | 32 (28–50) | 32 (28–44) | 36 (28–100) | 0.002 |
| Clinical findings c , N (%) | ||||
| Symptom duration on presentation (days) | 7 (5–10) | 5 (3–7) | 4 (2–7) | <0.001 |
| QTc (ms) | 431 (415–449) | 442 (420.5–461) | 450 (427–472) | <0.001 |
| Creatinine (mg/dL) | 0.88 (0.7–1.02) | 0.98 (0.77–1.39) | 1.31 (0.97–2.69) | <0.001 |
| Alanine aminotransferase (IU/L) | 38 (24–61) | 26 (16–45) | 21 (15–37) | <0.001 |
| Aspartate aminotransferase (IU/L) | 45 (31–68) | 41 (29.5–61.5) | 36 (28–60) | 0.007 |
| Lymphocyte count (K/uL) | 0.91 (0.67–1.22) | 0.78 (0.51–1.13) | 0.76 (0.49–1.24) | <0.001 |
| International normalized ratio | 1.2 (1.1–1.2) | 1.1 (1.1–1.3) | 1.1 (1.1–1.3) | 0.875 |
| Troponin (ng/mL) | 0.01 (0.01–0.01) | 0.01 (0.01–0.02) | 0.04 (0.01–0.1) | <0.001 |
| ESR (mm/h) | 53 (31–73) | 57 (30–81) | 61 (37–81) | 0.025 |
| Ferritin (ng/mL) | 828 (418–1,550) | 654 (286–1206) | 912 (475–1898) | 0.754 |
| C‐reactive protein (mg/dL) | 9.2 (4.4–16.1) | 9.6 (4.8–16.4) | 11.0 (5.4–21.9) | 0.041 |
| d‐dimer (ng/mL) | 288 (195–441) | 459 (277–962) | 590 (347–1,401) | <0.001 |
| Procalcitonin (ng/mL) | 0.15 (0.10–0.28) | 0.19 (0.12–0.4) | 0.45 (0.2–1.2) | <0.001 |
| Lactate dehydrogenase (IU/L) d | 385 (301–495) | 354 (269–482) | 379 (290–521) | 0.996 |
| Creatine phosphokinase (IU/L) e | 146 (66–321) | 138 (59–285) | 118 (61–365) | 0.674 |
| Interleukin‐6 (pg/mL) | 49.2 (24.6–87.6) | 69.9 (34.3–111.4) | 54.4 (26.0–117.6) | 0.084 |
Values are N (%) or median (25th–75th percentile).
Categories of NT‐proBNP are defined per Heart Failure Association of the European Society of Cardiology practical guidance statement on natriuretic peptides, Eur J Heart Fail 2019:21; 715–731. Low NT‐proBNP (‘heart failure unlikely’) is defined as <300 ng/mL. Borderline NT‐proBNP (‘grey zone’) is defined as 300–450 ng/mL for ages <50; 300–900 ng/mL for ages 50–75; and 300–1800 ng/mL for ages >75. High NT‐proBNP (‘heart failure likely’) is defined as >450 ng/mL for ages <50; >900 ng/mL for ages 50–75; and >1800 ng/mL for ages >75.
Non‐parametric test for trend across ordered categories.
Findings within 48 h of admission.
Available in 367 patients.
Available in 362 patients.
ACE, angiotensin converting enzyme; ESR, erythrocyte sedimentation rate; NT‐proBNP, N‐terminal pro‐B‐type natriuretic peptide; QTc, corrected QT interval on electrocardiogram.