Table 1.
Baseline characteristics overall and by dipstick proteinuria value
| Characteristics, N (%) | Overall N=11,229 |
Negative/Trace n=7956 |
30 mg/dl n=1700 |
100 mg/dl n=1219 |
≥300 mg/dl n=354 |
P Value |
|---|---|---|---|---|---|---|
| Male sex, n/total n (%) | 5165/11,227 (46.0) | 3549/7954 (44.6)2c | 807 (47.5) | 629 (51.6) | 180 (50.8) | <0.001 |
| Age, yr, mean±SD | 58.3±17.0 | 58.0±16.71a,2c | 58.9±17.8 | 59.9±17.46a | 57.4±17.4 | <0.001 |
| Race, n/total n (%) | <0.001a | |||||
| White | 6017/9756 (61.7) | 4346/6804 (63.9) | 896/1527 (58.7) | 623/1103 (56.5) | 152/322 (47.2) | |
| Black | 2502/9756 (25.6) | 1500/6804 (22.0) | 492/1527 (32.2) | 382/1103 (34.6) | 128/322 (39.8) | |
| Asian | 844/9756 (8.7) | 700/6804 (10.3) | 79/1527 (5.2) | 49/1103 (4.4) | 16/322 (5.0) | |
| American Indian or Alaska Native | 49/9756 (0.5) | 35/6804 (0.5) | 8/1527 (0.5) | 5/1103 (0.5) | 1/322 (0.3) | |
| Native Hawaiian or Other Pacific Islander | 16/9756 (0.2) | 11/6804 (0.2) | 3/1527 (0.2) | 2/1103 (0.2) | 0/322 (0.0) | |
| Other | 328/9756 (3.4) | 212/6804 (3.1) | 49/1527 (3.2) | 42/1103 (3.8) | 25/322 (7.8) | |
| Diabetes mellitus, n (%) | 3090 (27.5) | 1828 (23.0)1c,2c,3c | 591 (34.8)4b,5c | 494 (40.5)6b | 177 (50.0) | <0.001 |
| Hypertension, n (%) | 5756 (51.3) | 3640 (45.8)1c,2c,3c | 1046 (61.5)4b,5b | 818 (67.1) | 252 (71.2) | <0.001 |
| CAD, n/total n (%) | 1331/6203 (21.5) | 803/3932 (20.4) | 262/1137 (23.0) | 212/867 (24.5) | 54/267 (20.2) | 0.04 |
| ACEi/ARB, n/total n (%) | 3370/6203 (54.3) | 2124/3932 (54.0) | 624/1137 (54.9) | 493/867 (56.9) | 129/267 (48.3) | 0.9 |
| SG, median (IQR) | 1.016 (1.011–1.021) | 1.015 (1.011–1.020)1c,2c,3b | 1.019 (1.014–1.025)4c,5c | 1.016 (1.012–1.021) | 1.016 (1.013, 1.020) | <0.001 |
| eGFR, mean±SD, ml/min per 1.73 m2 | 71.81±31.48 | 77.49±28.061c,2c,3c | 67.24±33.504c,5c | 51.51±33.576c | 39.06±32.46 | <0.001 |
| eGFR ≥60 ml/min per 1.73 m2, n/total n (%) | 6122/9722 (63.0) | 4896/6868 (71.3)1c,2c,3c | 808/1463 (55.2)4c,5c | 352/1065 (33.1)6c | 66/326 (20.2) | <0.001 |
| eGFR cutoffs, ml/min per 1.73 m 2 , n/total n (%) | <0.001b | |||||
| ≥90 | 3161/9722 (32.5) | 2518/6868 (36.7) | 439/1463 (30.0) | 168/1065 (15.8) | 36/326 (11.0) | |
| 60–89 | 2961/9722 (30.5) | 2378/6868 (34.6) | 369/1463 (25.2) | 184/1065 (17.3) | 30/326 (9.2) | |
| 45–59 | 1389/9722 (14.3) | 985/6868 (14.3) | 202/1463 (13.8) | 170/1065 (16.0) | 32/326 (9.8) | |
| 30–44 | 1131/9722 (11.6) | 642/6868 (9.3) | 219/1463 (15.0) | 209/1065 (19.6) | 61/326 (18.7) | |
| 15–29 | 746/9722 (7.7) | 299/6868 (4.4) | 159/1463 (10.9) | 200/1065 (18.8) | 88/326 (27.0) | |
| <15 | 334/9722 (3.4) | 46/6868 (0.7) | 75/1463 (5.1) | 134/1065 (12.6) | 79/326 (24.2) | |
To compare across dipstick proteinuria categories, we used the Cochran–Armitage trend test for binary categorical variables, generalized Pearson chi-square test for the nominal categorical variable with more than two levels and linear-by-linear association test for ordinal categorical variable with more than two levels. We applied the Jonckheere–Terpstra test for continuous variables. Pairwise comparisons among negative or trace, 30, 100, and ≥300 mg/dl were performed when the overall test was significant, and the adjustment to P values was based on the Holm method. Pairwise for race value and GFR cutoffs are for overall differences. ACEi/ARB, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers; CAD, coronary artery disease; IQR, interquartile range; SG, specific gravity; UACR, urine albumin-to-creatinine ratio; UPCR, urine protein-to-creatinine ratio.
Pairwise comparison between negative/trace and 30 mg/dl: 1aP < 0.05, 1bP < 0.01, 1cP < 0.001.
Pairwise comparison between negative/trace and 100 mg/dl: 2aP < 0.05, 2bP < 0.01, 2cP < 0.001.
Pairwise comparison between negative/trace and ≥300 mg/dl: 3aP < 0.05, 3bP < 0.01, 3cP < 0.001.
Pairwise comparison between 30 and 100 mg/dl: 4aP < 0.05, 4bP < 0.01, 4cP < 0.001.
Pairwise comparison between 30 and ≥300 mg/dl: 5aP < 0.05, 5bP < 0.01, 5cP < 0.001.
Pairwise comparison between 100 and ≥300 mg/dl: 6aP < 0.05, 6bP < 0.01, 6cP < 0.001.
Pairwise comparison for overall race variable: 1c, 2c, 3c, 5c, 6a.
Pairwise comparison for overall eGFR cutoffs: 1c, 2c, 3c, 4c, 5c, 6c