Table 1. Baseline Characteristics (N=25,530).
| Characteristic | Entire Cohort (N=25,530) |
No Stress PSS=0 (n=6,501) |
Low Stress 1≤ PSS ≤3 (n=8,616) |
Moderate Stress 4≤ PSS ≤5 (n=4,978) |
High Stress PSS > 5 (n=5,435) |
P-value* |
|---|---|---|---|---|---|---|
| Age, mean (SD), years | 65 (9.4) | 66 (8.8) | 65 (9.3) | 65 (9.6) | 64 (9.9) | <0.0001 |
| Male (%) | 11,670 (46) | 3,657 (56) | 4,020 (47) | 2,146 (43) | 1,847 (34) | <0.0001 |
| Black (%) | 10,373 (41) | 2,607 (40) | 2,859 (33) | 2,147 (43) | 2,760 (51) | <0.0001 |
| Region | ||||||
| Stroke buckle (%) | 5,367 (21) | 1,308 (20) | 1,747 (20) | 1,084 (22) | 1,228 (23) | |
| Stroke belt (%) | 8,824 (35) | 2,215 (34) | 2,893 (34) | 1,732 (35) | 1,984 (37) | |
| Non-belt (%) | 11,339 (44) | 2,978 (46) | 3,976 (46) | 2,162 (43) | 2,223 (41) | <0.0001 |
| Education, high school or less (%) | 9,693 (38) | 2,312 (36) | 2,683 (31) | 2,021 (41) | 2,677 (49) | <0.0001 |
| Annual income, <$35,000 (%) | 10,674 (42) | 2,458 (38) | 2,985 (35) | 2,252 (45) | 2,979 (55) | <0.0001 |
| Body mass index, mean (SD), kg/m2 | 29 (6.1) | 29 (5.6) | 29 (6.0) | 29 (6.3) | 30 (6.8) | <0.0001 |
| Alcohol consumption | ||||||
| Heavy (%) | 991 (4.0) | 307 (4.7) | 352 (4.1) | 163 (3.3) | 169 (3.1) | |
| Moderate (%) | 8,469 (33) | 2,200 (34) | 3,146 (37) | 1,598 (32) | 1,525 (28) | |
| None (%) | 16,070 (63) | 3,994 (61) | 5,118 (59) | 3,217 (65) | 3,741 (69) | <0.0001 |
| Exercise | ||||||
| 4 or more times per week (%) | 7,509 (29) | 2,254 (35) | 2,625 (30) | 1,380 (28) | 1,250 (23) | |
| 1 to 3 times per week (%) | 9,161 (36) | 2,235 (34) | 3,239 (38) | 1,861 (37) | 1,826 (34) | |
| None (%) | 8,860 (35) | 2,012 (31) | 2,752 (32) | 1,737 (35) | 2,359 (43) | <0.0001 |
| Ever smoker (%) | 13,922 (55) | 3,691 (57) | 4,567 (53) | 2,659 (53) | 3,005 (55) | <0.0001 |
| Depression (%) | 2,738 (11) | 152 (2.3) | 366 (4.3) | 461 (9.3) | 1,759 (32) | <0.0001 |
| Diabetes (%) | 5,345 (21) | 1,322 (20) | 1,543 (18) | 1,093 (22) | 1,387 (26) | <0.0001 |
| Systolic blood pressure, mean (SD), mm Hg | 127 (17) | 128 (16) | 126 (16) | 127 (17) | 128 (18) | <0.0001 |
| Diastolic blood pressure, mean (SD), mm Hg | 76 (9.7) | 77 (9.4) | 76 (9.4) | 76 (9.7) | 77 (10) | <0.0001 |
| Pulse pressure, mean (SD), mm Hg | 51 (13) | 52 (13) | 50 (13) | 51 (14) | 51 (14) | <0.0001 |
| Total cholesterol, mean (SD), mg/dL | 192 (40) | 190 (40) | 192 (39) | 191 (39) | 194 (42) | <0.0001 |
| HDL cholesterol, mean (SD), mg/dL | 52 (16) | 51 (16) | 52 (16) | 52 (16) | 52 (16) | <0.0001 |
| Aspirin use (%) | 11,144 (44) | 2,982 (46) | 3,763 (44) | 2,082 (42) | 2,317 (43) | <0.0001 |
| Antihypertensive medication use (%) | 13,578 (53) | 3,449 (53) | 4,269 (50) | 2,643 (53) | 3,217 (59) | <0.0001 |
| Lipid-lowering medication use (%) | 8,591 (34) | 2,176 (33) | 2,789 (32) | 1,730 (35) | 1,896 (35) | 0.0050 |
| Left ventricular hypertrophy (%) | 2,526 (9.9) | 658 (10) | 757 (8.8) | 483 (9.7) | 628 (12) | <0.0001 |
| Cardiovascular disease (%) | 5,484 (21) | 1,389 (21) | 1,613 (19) | 1,119 (22) | 1,363 (25) | <0.0001 |
*
Statistical significance for categorical variables tested using the chi-square method and for continuous variables the Kruskal-Wallis procedure was used.
HDL, high-density lipoprotein; PSS, perceived stress scale; SD, standard deviation.