Table 1.
Characteristics of the study participants at baseline, according to estimated sodium excretion (conditional analysis)
| Characteristic | Case | Control | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Estimated sodium excretion | ||||||||||
| All | <2.8 g/day | 2.8–3.5 g/day | 3.5–4.3 g/day | >4.3 g/day | All | <2.8 g/day | 2.8–3.5 g/day | 3.5–4.3 g/day | >4.3 g/day | |
| (N = 8,761) | (N = 2,214) | (N = 1,911) | (N = 2,065) | (N = 2,571) | (N = 8,767) | (N = 2,075) | (N = 2,481) | (N = 2,352) | (N = 1,859) | |
| Estimated excretion, g/day | ||||||||||
| Sodium | 3.69 ± 1.28 | 2.23 ± 0.44 | 3.19 ± 0.20 | 3.88 ± 0.21 | 5.18 ± 1.02 | 3.54 ± 1.04 | 2.32 ± 0.41 | 3.19 ± 0.20 | 3.88 ± 0.21 | 4.93 ± 0.93 |
| Potassium | 1.58 ± 0.38 | 1.43 ± 0.30 | 1.49 ± 0.33 | 1.56 ± 0.34 | 1.78 ± 0.42 | 1.68 ± 0.42 | 1.48 ± 0.35 | 1.62 ± 0.39 | 1.75 ± 0.40 | 1.88 ± 0.44 |
| Age, year | 62.9 ± 13.4 | 63.9 ± 13.7 | 63.0 ± 13.4 | 62.5 ± 13.2 | 62.3 ± 13.2 | 62.1 ± 13.2 | 63.7 ± 13.5 | 62.0 ± 13.2 | 61.3 ± 12.9 | 61.5 ± 13.0 |
| Female sex, no. (%) | 3,574 (40.8) | 959 (26.8) | 770 (21.5) | 797 (22.3) | 1,048 (29.3) | 3,580 (40.8) | 925 (25.8) | 978 (27.3) | 929 (25.9) | 748 (20.9) |
| Geographic region, no. (%) | ||||||||||
| Western Europe/North America | 1,544 (17.6) | 567 (36.7) | 394 (25.5) | 302 (19.6) | 281 (18.2) | 1,544 (17.6) | 381 (24.7) | 439 (28.4) | 447 (29.0) | 277 (17.9) |
| Eastern/Central Europe/ Middle East | 1,079 (12.3) | 206 (19.1) | 213 (19.7) | 290 (26.9) | 370 (34.3) | 1,079 (12.3) | 211 (19.6) | 287 (26.6) | 322 (29.8) | 259 (24.0) |
| Africa | 587 (6.70) | 278 (47.4) | 126 (21.5) | 90 (15.3) | 93 (15.8) | 587 (6.70) | 213 (36.3) | 192 (32.7) | 118 (20.1) | 64 (10.9) |
| China | 3,891 (44.4) | 728 (18.7) | 836 (21.5) | 1,053 (27.1) | 1,274 (32.7) | 3,891 (44.4) | 832 (21.4) | 1,089 (28.0) | 1,051 (27.0) | 919 (23.6) |
| South East Asia | 615 (7.02) | 155 (25.2) | 123 (20.0) | 125 (20.3) | 212 (34.5) | 615 (7.01) | 204 (33.2) | 214 (34.8) | 126 (20.5) | 71 (11.5) |
| South America | 1,045 (11.9) | 280 (26.8) | 219 (21.0) | 205 (19.6) | 341 (32.6) | 1,051 (12.0) | 234 (22.3) | 260 (24.7) | 288 (27.4) | 269 (25.6) |
| Stroke type, no. (%) | ||||||||||
| Ischemic | 6,805 (77.7) | 1,710 (77.4) | 1,537 (81.0) | 1,646 (80.0) | 1,912 (74.7) | — | — | — | — | — |
| ICH | 1,919 (21.9) | 499 (22.6) | 361 (19.0) | 411 (20.0) | 648 (25.3) | — | — | — | — | — |
| Hypertension, no. (%) | 5,243 (59.8) | 1,363 (61.6) | 1,134 (59.3) | 1,192 (57.7) | 1,554 (60.4) | 3,299 (37.6) | 974 (46.9) | 998 (40.2) | 988 (42.0) | 856 (46.0) |
| Blood pressure, mm Hg | ||||||||||
| Systolic | 148 ± 21.2 | 149 ± 22.0 | 147 ± 20.8 | 148 ± 20.5 | 149 ± 21.3 | 133 ± 18.5 | 133 ± 19.1 | 133 ± 18.3 | 133 ± 17.8 | 134 ± 18.7 |
| Diastolic | 86.5 ± 12.3 | 87.0 ± 13.2 | 85.4 ± 12.1 | 86.5 ± 11.8 | 86.9 ± 12.0 | 80.1 ± 10.7 | 79.3 ± 11.2 | 79.8 ± 10.5 | 80.3 ± 10.3 | 81.1 ± 10.6 |
| Cholesterol, mmol/l | ||||||||||
| HDL | 1.15 ± 0.35 | 1.18 ± 0.37 | 1.16 ± 0.37 | 1.14 ± 0.34 | 1.12 ± 0.33 | 1.22 ± 0.37 | 1.22 ± 0.38 | 1.23 ± 0.38 | 1.21 ± 0.35 | 1.20 ± 0.37 |
| LDL | 2.97 ± 1.01 | 3.03 ± 1.08 | 2.96 ± 0.98 | 2.99 ± 0.99 | 2.91 ± 0.98 | 2.98 ± 0.96 | 2.98 ± 1.01 | 3.04 ± 0.97 | 2.97 ± 0.94 | 2.90 ± 0.92 |
| Diabetes mellitus, no. (%) | 1,486 (17.0) | 355 (16.0) | 315 (16.5) | 359 (17.4) | 457 (17.8) | 1,108 (12.6) | 283 (13.6) | 304 (12.3) | 303 (12.9) | 218 (11.7) |
| AFIB/atrial flutter, no. (%) | 936 (10.7) | 301 (13.6) | 210 (11.0) | 170 (8.23) | 255 (9.92) | 270 (3.08) | 74 (3.57) | 69 (2.78) | 61 (2.59) | 66 (3.55) |
| Diuretic preadmission, no. (%) | 1,132 (12.9) | 298 (13.5) | 260 (13.6) | 229 (11.1) | 345 (13.4) | 782 (8.92) | 194 (9.35) | 185 (7.46) | 204 (8.68) | 199 (10.7) |
| Diuretic in hospital, no. (%) | 1,994 (22.8) | 537 (24.3) | 418 (21.9) | 441 (21.4) | 598 (23.3) | 352 (12.8) | 73 (11.3) | 80 (10.2) | 95 (13.7) | 104 (16.3) |
| Current smoker, no. (%) | 2,623 (29.9) | 610 (27.6) | 591 (30.9) | 666 (32.3) | 756 (29.4) | 1,850 (21.1) | 429 (20.7) | 522 (21.0) | 510 (21.7) | 389 (20.9) |
Abbreviations: AFIB, atrial fibrillation; HDL, high-density lipoprotein; ICH, intracerebral hemorrhage; LDL, low-density lipoprotein.