Demographic and clinical characteristics of the participants
| Total | All-negative group | Once-positive group | Repetitively-positive group | P value | |
| N | 88 744 | 74 471 | 8775 | 5498 | |
| Age, years | 51.6±7.9 | 51.7±7.9 | 50.7±7.8 | 52.4±8.0 | <0.001 |
| Female, no. (%) | 25 341 (28.6%) | 22 944 (30.8%) | 1760 (20.1%) | 637 (11.6%) | <0.001 |
| Body mass index, kg/m2 | 23.7±3.6 | 23.5±3.4 | 24.4±3.9 | 25.9±4.5 | <0.001 |
| Estimated glomerular filtration rate, mL/min/1.73 m2 | 78.4±13.9 | 78.6±13.3 | 78.7±14.3 | 74.8±19.0 | <0.001 |
| Baseline proteinuria,* no. (%) | |||||
| – | 77 729 (87.9%) | 69 361 (93.4%) | 6318 (72.0%) | 2050 (37.4%) | <0.001 |
| ± | 7024 (7.9%) | 4864 (6.6%) | 1254 (14.3%) | 906 (16.5%) | |
| 1+ | 2616 (3.0%) | 0 (0.0%) | 1043 (11.9%) | 1573 (28.7%) | |
| 2+ | 864 (1.0%) | 0 (0.0%) | 142 (1.6%) | 722 (13.2%) | |
| 3+ | 246 (0.3%) | 0 (0.0%) | 14 (0.2%) | 232 (4.2%) | |
| Systolic blood pressure, mm Hg | 124±17 | 123.5±16.4 | 126.7±17.3 | 132.2±18.9 | <0.001 |
| Diastolic blood pressure, mm Hg | 77±12 | 76.5±11.8 | 79.1±12.6 | 82.7±12.7 | <0.001 |
| Haemoglobin A1c, % | 5.6±0.7 | 5.6±0.6 | 5.7±0.9 | 6.1±1.2 | <0.001 |
| LDL cholesterol, mg/dL | 128±32.1 | 128.3±31.9 | 128.3±33.1 | 127.1±33.7 | 0.023 |
| Use of antihypertensive drugs, no. (%) | 14 232 (16.1%) | 10 452 (14.0%) | 1751 (20.0%) | 2029 (37.0%) | <0.001 |
| Use of antidiabetic drugs, no. (%) | 4368 (4.9%) | 2822 (3.8%) | 624 (7.1%) | 922 (16.8%) | <0.001 |
| Use of antihyperlipidaemic drugs, no. (%) | 8612 (9.7%) | 6737 (9.1%) | 880 (10.0%) | 995 (18.1%) | <0.001 |
| Current smoking status, no. (%) | 24 680 (27.8%) | 19 520 (26.2%) | 3030 (34.6%) | 2130 (38.8%) | <0.001 |
| History of stroke, no. (%) | 1085 (1.3%) | 817 (1.1%) | 113 (1.3%) | 155 (2.9%) | <0.001 |
| History of cardiovascular disease, no. (%) | 1996 (2.3%) | 1503 (2.1%) | 234 (2.7%) | 259 (4.8%) | <0.001 |
Variables are presented as mean±SD or n (%).
*Baseline proteinuria represents urine test results at the beginning of the observation period, which was defined as visit 1.
LDL, low-density lipoprotein.