Table 1 Comparison of baseline characteristics between derivation and validation samples

Patient Characteristics

Index Event

 Index Event

0.404

 Emergency Department-Only

32.4 (1702)

31.6 (1343)

 Admitted

67.6 (3548)

68.4 (2905)

 Weekday presentation

79.9 (4196)

79.8 (3388)

0.839

 Left Against Medical Advice (AMA)

4.5 (235)

5.0 (214)

0.200

Demographics

 Age (years): mean ± standard deviation

70.41 (11.27)

70.46 (11.31)

0.811

 Median (IQR)*

70.0 (64.0–78.0)

70.0 (64.0–78.0)

0.958

 Male Gender

94.9 (4983)

94.8 (4028)

0.838

 Race

0.960

 White

75.7 (3972)

75.8 (3221)

 Black

19.7 (1034)

19.7 (837)

 Asian

0.5 (26)

0.6 (24)

 Other

0.7 (36)

0.6 (26)

 Unknown

3.5 (182)

3.3 (140)

 Hispanic ethnicity

7.2 (380)

7.3 (311)

Past Medical History

 Transient Ischemic Attack (TIA) in prior 30 days

4.4 (230)

3.6 (155)

0.072

 Stroke in prior 30 days

5.8 (302)

5.7 (243)

0.947

 Diabetes mellitus

42.4 (2226)

43.1 (1832)

0.477

 Atrial fibrillation

16.8 (883)

17.0 (724)

0.772

 Myocardial infarction

6.9 (362)

7.7 (328)

0.123

 Congestive heart failure

15.0 (789)

15.4 (655)

0.598

 Carotid endarterectomy or stent

1.0 (50)

0.8 (36)

0.591

 Chronic obstructive pulmonary disease (COPD)

21.8 (1147)

22.2 (942)

0.702

 Peripheral arterial disease

14.2 (745)

14.7 (625)

0.471

 Dementia

8.0 (418)

7.3 (309)

0.210

 Chronic kidney disease

17.4 (916)

18.4 (781)

0.236

Past Medical History

 Dialysis

1.5 (78)

1.3 (57)

0.556

 Cancer

11.3 (592)

11.7 (499)

0.475

 Hypertension

75.8 (3982)

77.5 (3292)

0.059

 Hyperlipidemia

61.3 (3218)

63.0 (2678)

0.081

 Speech deficit

4.6 (239)

5.1 (217)

0.208

 Motor deficit, hemiplegia

14.6 (766)

16.3 (692)

0.022

 Sleep apnea

19.3 (1015)

19.1 (812)

0.788

 Alcohol dependence

7.4 (388)

8.2 (350)

0.125

 Depression

22.9 (1200)

23.8 (1012)

0.268

 History of venous thromboembolism (deep vein thrombosis or pulmonary embolism)

3.4 (177)

3.2 (136)

0.645

 Intracranial hemorrhage

5.0 (263)

5.4 (229)

0.405

 Gastrointestinal bleeding

0.7 (37)

0.6 (26)

0.580

 Migraine

3.2 (169)

3.6 (151)

0.368

Medications prior to index event

 Antihypertensives

85.6 (4493)

86.0 (3653)

0.567

 Statin

80.9 (4247)

82.6 (3509)

0.032

 Aspirin

75.0 (3940)

74.7 (3173)

0.693

 Warfarin

11.7 (613)

10.3 (439)

0.038

Comorbidity

 CHA2DS2−VASc*

3.21 (1.45)

3.21 (1.43)

0.937

 HASBLED*

2.22 (1.06)

2.22 (1.04)

0.993

 Charlson: mean ± standard deviation

2.83 (2.64)

2.92 (2.70)

0.081

 Median (IQR)

2.0 (1.0–4.0)

2.0 (1.0–4.0)

0.111

Smoker

28.4 (1493)

29.5 (1253)

0.258

Palliative care, hospice

3.0 (160)

2.6 (112)

0.232

Present on Admission

 Concomitant Myocardial Infarction (MI)

2.0 (105)

2.4 (101)

0.209

 Concomitant Congestive Heart Failure (CHF)

1.9 (100)

1.7 (74)

0.556

Laboratory and Vital Signs

 APACHE:* mean ± standard deviation

9.83 (6.75)

10.14 (6.70)

0.026

 Median (IQR)

9.0 (4.0–14.0)

9.0 (5.0–14.0)

0.007

First Systolic blood pressure (mm Hg):

 Mean Systolic (SD)

147.41 (25.38)

146.78 (25.05)

0.226

 Median Systolic (IQR)

146.0 (130.0–164.0)

146.0 (130.0–163.0)

0.320

First Diastolic blood pressure (mm Hg):

 Mean Diastolic (SD)

81.25 (14.20)

81.31 (14.09)

0.846

 Median Diastolic (IQR)

80.0 (72.0–90.0)

81.0 (72.0–90.0)

0.721

Average Systolic blood pressure 90 days post discharge (mm Hg):

 Mean Systolic (SD)

131.10 (15.35)

130.59 (15.63)

0.144

 Median Systolic (IQR)

131.0 (121.0–140.0)

130.0 (120.0–139.5)

0.132

Average Diastolic blood pressure 90 days post discharge (mm Hg):

 Mean Diastolic (SD)

74.42 (9.84)

74.21 (9.78)

0.334

 Median Diastolic (IQR)

74.6 (68.0–81.0)

74.0 (68.0–80.5)

0.309

Outcomes

 Death 90-days

2.2 (116)

2.1 (88)

0.645

 Death 1-year

7.7 (405)

7.1 (303)

0.283

 Stroke 90-days

3.2 (164)

3.2 (134)

0.943

 Stroke 1-year

5.3 (257)

5.6 (224)

0.444

 Stroke or Death 90-days

5.2 (272)

5.1 (215)

0.793

 Stroke or Death 1-year

12.0 (629)

11.8 (500)

0.752