Table I.

Baseline characteristics of β-blocker and non-β-blocker patients in the case study

	Median (25th percentile–75th percentile) or N (%)
Baseline characteristics	β-blocker: No (N = 5535)	β-blocker: Yes (N = 2078)	Standardized difference	P-value
Demographic characteristics
Age (years)	78 (70–84)	75 (67–82)	0.24	<0.001
Female	2809 (50.7%)	1011 (48.7%)	0.04	0.103
Vital signs on admission
Systolic blood pressure, mmHg	147 (127–170)	150 (130–176)	0.13	<0.001
Heart rate, beats per minute	94 (78–111)	88 (73–108)	0.14	<0.001
Respiratory rate, breaths per minute	24 (20–30)	24 (20–28)	0.09	<0.001
Presenting symptoms and physical exam
Neck vein distension	3002 (54.2%)	1200 (57.7%)	0.07	0.006
S3	518 (9.4%)	232 (11.2%)	0.06	0.018
S4	204 (3.7%)	89 (4.3%)	0.03	0.227
Rales > 50% of lung field	560 (10.1%)	231 (11.1%)	0.03	0.203
Findings on chest X-ray
Pulmonary edema	2772 (50.1%)	1137 (54.7%)	0.09	<0.001
Cardiomegaly	2026 (36.6%)	711 (34.2%)	0.05	0.053
Past medical history
Diabetes	1871 (33.8%)	804 (38.7%)	0.1	<0.001
CVA/TIA	880 (15.9%)	340 (16.4%)	0.01	0.624
Previous MI	1815 (32.8%)	989 (47.6%)	0.31	<0.001
Atrial fibrillation	1675 (30.3%)	530 (25.5%)	0.1	<0.001
Peripheral vascular disease	684 (12.4%)	302 (14.5%)	0.06	0.012
Chronic obstructive pulmonary disease	1074 (19.4%)	191 (9.2%)	0.28	<0.001
Dementia	422 (7.6%)	91 (4.4%)	0.13	<0.001
Cirrhosis	48 (0.9%)	6 (0.3%)	0.07	0.007
Cancer	659 (11.9%)	195 (9.4%)	0.08	0.002
Electrocardiogram – First available within 48 h
Left bundle branch block	834 (15.1%)	293 (14.1%)	0.03	0.29
Laboratory tests
Hemoglobin, g/L	124 (110–138)	125 (111–139)	0.05	0.146
White blood count, 10E9/L	9 (7–12)	9 (7–11)	0.02	0.261
Sodium, mmol/L	139 (136–141)	139 (137–141)	0.08	0.001
Potassium, mmol/L	4 (4–5)	4 (4–5)	0.03	0.12
Glucose, mmol/L	7 (6–11)	8 (6–12)	0.09	<0.001
Blood urea nitrogen, mmol/L	8 (6–12)	8 (6–12)	0	0.522
Creatinine, μmol/L	104 (82–142)	107 (85–144)	0.08	0.002