Table 1.
Baseline characteristics of the study population.
| Characteristics | Proteinuria Measured by Dipstick | p-Value | |||
|---|---|---|---|---|---|
| Negative | Trace (±) | 1+ | ≥ 2+ | ||
| No. (%) | 9,444,344 (95.2) | 224,793 (2.3) | 167,324 (1.7) | 80,939 (0.8) | |
| Age, years † | 46.9 ± 14.0 | 48.9 ± 14.2 | 51.1 ± 14.5 | 53.2 ± 14.3 | <0.001 |
| 20–64 | 8,243,115 (87.3) | 189,309 (84.2) | 133,790 (80.0) | 61,528 (76.0) | <0.001 |
| 65–110 | 1,201,229 (12.7) | 35,484 (15.8) | 33,534 (20.0) | 19,411 (24.0) | |
| Male | 5,177,903 (54.8) | 121,349 (54.0) | 90,214 (53.9) | 45,386 (56.1) | <0.001 |
| Urban residence | 4,340,165 (46.0) | 109,178 (48.6) | 80,618 (48.2) | 37,299 (46.1) | <0.001 |
| Smoking status | <0.001 | ||||
| Nonsmokers | 5,614,771 (59.5) | 134,436 (59.8) | 100,081 (59.8) | 47,878 (59.2) | |
| Former smokers | 1,351,140 (14.3) | 33,116 (14.7) | 25,809 (15.4) | 13,498 (16.7) | |
| Current smokers | 2,478,433 (26.2) | 57,241 (25.5) | 41,434 (24.8) | 19,563 (24.2) | |
| Heavy drinker ‡ | 643,540 (6.8) | 16,784 (7.5) | 13,153 (7.9) | 6518 (8.1) | <0.001 |
| Regular exercise § | 4,870,116 (51.6) | 114,758 (51.1) | 81,648 (48.8) | 37,829 (46.7) | <0.001 |
| BMI, kg/m2 † | 23.7 ± 3.2 | 24.0 ± 3.4 | 24.3 ± 3.5 | 24.6 ± 3.7 | <0.001 |
| Height, cm † | 163.9 ± 9.2 | 163.6 ± 9.1 | 163.0 ± 9.1 | 162.6 ± 9.1 | <0.001 |
| Weight, kg † | 63.9 ± 11.6 | 64.4 ± 11.9 | 64.7 ± 12.1 | 65.3 ± 12.5 | <0.001 |
| Systolic blood pressure, mmHg † | 122.2 ± 14.8 | 124.1 ± 16.1 | 126.5 ± 17.0 | 129.8 ± 18.1 | <0.001 |
| Diastolic blood pressure, mmHg† | 76.2 ± 9.9 | 77.2 ± 10.6 | 78.43 ± 11.0 | 79.9 ± 11.4 | <0.001 |
| Fasting glucose, mg/dL † | 96.70 ± 21.9 | 101.7 ± 29.5 | 107.7 ± 37.0 | 115.2 ± 44.8 | <0.001 |
| Total cholesterol, mg/dL † | 194.8 ± 36.4 | 197.6 ± 38.3 | 199.6 ± 40.2 | 202.4 ± 43.4 | <0.001 |
| Creatinine, mg/dL † | 1.0 ± 0.9 | 1.1 ± 1.1 | 1.1 ± 1.0 | 1.2 ± 1.0 | <0.001 |
| eGFR, mL/min/1.73 m2 † | 88.6 ± 44.5 | 85.0 ± 31.5 | 82.8 ± 33.9 | 77.4 ± 35.4 | <0.001 |
| Comorbidity | |||||
| Diabetes mellitus | 2,353,771 (24.9) | 75,690 (33.7) | 72,603 (43.4) | 45,808 (56.6) | <0.001 |
| Hypertension | 767,049 (8.1) | 32,227 (14.3) | 36,117 (21.6) | 25,807 (31.9) | <0.001 |
| Dyslipidemia | 1,683,466 (17.8) | 51,939 (23.1) | 47,233 (28.2) | 29,879 (36.9) | <0.001 |
BMI, body mass index; eGFR, estimated glomerular filtration rate; No., number. † Mean ± standard deviation. ‡ Defined as a person who consumed at least 30 g of alcohol per day. § Defined as high-intensity exercise for at least 20 min or moderate-intensity exercise for at least 30 min at a time at least once a week.