Table 4.
Baseline Characteristics Based on SES
| Characteristic | Lower SES, n = 383a | Upper SES, n = 359a | P Value |
|---|---|---|---|
| Age, y | 60 ± 13 | 57 ± 12 | 0.002 |
| Male sex | 222 (58) | 204 (57) | 0.75 |
| Chest pain or dyspnea | 226 (59) | 191 (53) | 0.11 |
| HTN | 245 (64) | 167 (47) | <0.001 |
| DM | 138 (36) | 46 (13) | <0.001 |
| Dyslipidemia | 203 (53) | 135 (38) | <0.001 |
| Tobacco use | 50 (13) | 33 (9) | 0.10 |
| Family history of CAD | 107 (28) | 167 (47) | <0.001 |
| Framingham 10‐year CHD risk, % | 15 ± 11 | 11 ± 10 | <0.001 |
| Likelihood of obstructive CAD, %b | 19 ± 12 | 17 ± 9 | 0.02 |
| Pharmacologic stress | 121 (32) | 55 (15) | <0.001 |
| Uninterpretable ECGc | 7 (12) | 6 (1.7) | 0.87 |
| BMI, kg/m2 | 31 ± 6 | 29 ± 6 | <0.001 |
| Known CAD | 86 (22) | 50 (14) | 0.003 |
| Physician specialty | <0.001 | ||
| Cardiology | 57 (15) | 11 (3) | |
| Primary care | 326 (85) | 348 (97) | |
| AUC classification | <0.001 | ||
| Appropriate | 220 (57) | 169 (47) | |
| Uncertain | 19 (5) | 7 (2) | |
| Inappropriate | 144 (38) | 183 (51) |
Abbreviations: AUC, appropriate use criteria; BMI, body mass index; CAD, coronary artery disease; CHD, coronary heart disease; DM, diabetes mellitus; ECG, electrocardiogram; HTN, hypertension; LBBB, left bundle branch block; SD, standard deviation.
Continuous variables are presented as mean ± SD. Dichotomous variables are presented as n (%). There were no missing baseline characteristics data.
Upper vs lower socioeconomic status is based on the top (≥$83 000) vs bottom (≤$55 000) quartile of median annual household income for the ZIP code of residence.
Based on Diamond and Forrester tables in patients with chest pain or dyspnea.14
Uninterpretable ECG for myocardial ischemia is defined as LBBB, paced ventricular rhythm, left ventricular hypertrophy with secondary ST‐segment abnormalities, Wolff‐Parkinson‐White pattern, or baseline ST‐segment depression ≥0.5 mm.