Table 1. Characteristics of Participants by Survey Years.
| Characteristic | Participants, No. (%)a | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1988-1994 (n = 14 255) | 1999-2000 (n = 3534) | 2001-2002 (n = 4371) | 2003-2004 (n = 4198) | 2005-2006 (n = 4250) | 2007-2008 (n = 5835) | 2009-2010 (n = 5123) | 2011-2012 (n = 4469) | 2013-2014 (n = 4896) | 2015-2016 (n = 4623) | |
| Age, mean (SE), y | 44.4 (0.48) | 45.4 (0.38) | 46.1 (0.51) | 46.3 (0.51) | 46.5 (0.73) | 46.7 (0.43) | 47.0 (0.51) | 47.1 (0.87) | 47.5 (0.38) | 47.8 (0.57) |
| Female sex | 7538 (51.8) | 1862 (51.7) | 2271 (51.7) | 2161 (51.3) | 2208 (52.0) | 2452 (51.8) | 2631 (51.6) | 2260 (51.7) | 2563 (51.5) | 2398 (52.0) |
| Race/ethnicity | ||||||||||
| Non-Hispanic white | 6175 (77.7) | 1629 (70.7) | 2337 (73.5) | 2241 (72.5) | 2165 (72.8) | 2362 (70.9) | 2609 (70.5) | 1745 (68.3) | 2191 (67.4) | 1593 (65.7) |
| Non-Hispanic black | 3775 (10.0) | 625 (9.8) | 774 (9.8) | 807 (10.9) | 944 (11.0) | 922 (10.0) | 867 (10.4) | 1109 (10.4) | 956 (10.7) | 930 (10.5) |
| Mexican American | 3744 (4.8) | 939 (7.1) | 935 (6.9) | 852 (7.8) | 841 (7.7) | 836 (8.3) | 890 (8.1) | 441 (7.5) | 623 (8.6) | 798 (8.5) |
| Other | 561 (7.4) | 341 (12.4) | 325 (9.9) | 298 (8.8) | 300 (8.5) | 715 (10.8) | 757 (11.0) | 1174 (13.7) | 1126 (13.3) | 1304 (15.2) |
| Educational level | ||||||||||
| <High school | 5626 (23.7) | 1304 (23.0) | 1297 (18.9) | 1216 (17.9) | 1152 (17.1) | 1463 (20.1) | 1413 (18.5) | 976 (15.3) | 1002 (14.6) | 1037 (13.5) |
| High school | 5318 (41.8) | 795 (25.8) | 1023 (25.2) | 1042 (26.6) | 1003 (24.6) | 1176 (24.6) | 1170 (22.8) | 928 (19.7) | 1107 (21.9) | 1008 (20.7) |
| >High school | 3311 (34.5) | 1435 (51.2) | 2051 (55.8) | 1940 (55.5) | 2095 (58.2) | 2196 (55.3) | 2540 (58.8) | 2565 (65.0) | 2788 (63.5) | 2578 (65.8) |
| Income | ||||||||||
| Low income | 3304 (12.3) | 719 (15.3) | 749 (13.4) | 784 (12.9) | 754 (11.1) | 1002 (14.0) | 1154 (14.6) | 1114 (17.3) | 1104 (15.9) | 1024 (14.2) |
| Middle income | 8535 (60.4) | 1902 (50.2) | 2324 (48.9) | 2316 (52.1) | 2315 (51.6) | 2593 (48.1) | 2709 (49.3) | 2209 (46.9) | 2531 (49.5) | 2508 (48.7) |
| High income | 2416 (27.3) | 913 (34.5) | 1298 (37.7) | 1098 (35.0) | 1181 (37.2) | 1240 (37.9) | 1260 (36.0) | 1146 (35.8) | 1261 (34.7) | 1091 (37.1) |
| eGFR, mean (SD), mL/min/1.73 m2b | 99.3 (0.52) | 94.3 (0.47) | 94.2 (0.74) | 94.1 (0.76) | 93.9 (1.0) | 95.7 (0.88) | 94.6 (0.70) | 94.9 (0.83) | 93.3 (0.54) | 95.6 (0.92) |
| ACR, mean (SD), mg/g | 24.0 (1.4) | 31.7 (6.1) | 29.9 (2.8) | 22.5 (2.4) | 30.2 (3.0) | 37.6 (4.4) | 23.3 (2.9) | 24.1 (2.1) | 41.6 (4.8) | 35.8 (3.3) |
Abbreviations: ACR, albumin to creatinine ratio; eGFR, estimated glomerular filtration rate.
a
Percentages are weighted.
b
Estimated from serum creatinine using the Chronic Kidney Disease Epidemiology Collaboration equation.16