Table 1 Descriptive characteristics of NHANES participants
Characteristics | General population | Population without CKD | Population with CKD | P-value |
|---|---|---|---|---|
Sex | 0.003 | |||
 Male | 4543 (46.74) | 3870 (46.35) | 673 (39.91) |  |
 Female | 5176 (53.26) | 4329 (53.65) | 847 (60.09) |  |
 Age in years | 53.96 (0.16) | 53.11 (0.17) | 59.81 (0.33) |  < 0.001 |
Age |  < 0.001 | |||
 40–50 | 3445 (35.45) | 3139 (41.58) | 306 (22.25) |  |
 50–60 | 2799 (28.8) | 2453 (33.80) | 346 (25.63) |  |
 60–70 | 2341 (24.09) | 1871 (18.02) | 470 (29.14) |  |
  >  = 70 | 1134 (11.67) | 736 (6.60) | 398 (22.97) |  |
Race |  < 0.001 | |||
 Mexican American | 1643 (16.91) | 1380 (7.29) | 263 (8.09) |  |
 Non-Hispanic White | 4002 (41.18) | 3400 (71.88) | 602 (67.58) |  |
 Non-Hispanic Black | 1925 (19.81) | 1559 (9.01) | 366 (12.62) |  |
 Other Races | 2149 (22.11) | 1860 (11.83) | 289 (11.71) |  |
Educational attainment |  < 0.001 | |||
  < 11th grade | 2683 (27.61) | 2177 (15.44) | 506 (21.18) |  |
 High school graduate | 2135 (21.97) | 1785 (21.71) | 350 (23.65) |  |
 Some college or AA degree | 2653 (27.3) | 2253 (30.48) | 400 (30.05) |  |
 College graduate or above | 2248 (23.13) | 1984 (32.37) | 264 (25.13) |  |
BMI |  < 0.001 | |||
 Normal | 2595 (26.7) | 2258 (28.33) | 337 (22.65) |  |
 Overweight | 3382 (34.8) | 2913 (35.92) | 469 (31.21) |  |
 Obese | 3742 (38.5) | 3028 (35.75) | 714 (46.13) |  |
Smoking status | 0.001 | |||
 Never | 5182 (53.32) | 4436 (54.41) | 746 (48.26) |  |
 Former | 2485 (25.57) | 2059 (26.21) | 426 (31.13) |  |
 Current | 2052 (21.11) | 1704 (19.38) | 348 (20.60) |  |
CVD |  < 0.001 | |||
 Yes | 721 (7.42) | 472 (4.44) | 249 (12.87) |  |
 No | 8998 (92.58) | 7727 (95.56) | 1271 (87.13) |  |
DM |  < 0.001 | |||
 Yes | 1670 (17.18) | 1131 (9.87) | 539 (28.48) |  |
 No | 8049 (82.82) | 7068 (90.13) | 981 (71.52) |  |
Hypertension |  < 0.001 | |||
 Yes | 4386 (45.13) | 3343 (36.94) | 1043 (63.34) |  |
 No | 5333 (54.87) | 4856 (63.06) | 477 (36.66) |  |
Klotho (pg/ml) | 859.53 (5.97) | 863.18 (6.36) | 834.54 (9.88) | 0.008 |
Biomarkers of lipid | ||||
 HDL (mg/dl) | 55.33 (0.35) | 55.42 (0.34) | 54.70 (1.01) | 0.464 |
 LDL (mg/dl) | 126.38 (0.74) | 126.77 (0.75) | 123.52 (1.92) | 0.094 |
 TC (mg/dl) | 209.94 (0.75) | 209.55 (0.75) | 212.68 (1.63) | 0.047 |
 TG (mg/dl) | 162.13 (2.16) | 159.07 (2.34) | 183.05 (4.67) |  < 0.001 |
Biomarkers of inflammation | ||||
 WBC (1000 cells/ul) | 6.57 (0.06) | 6.51 (0.06) | 7.01 (0.11) |  < 0.001 |
 Neu (1000 cell/ul) | 3.87 (0.04) | 3.82 (0.04) | 4.27 (0.09) |  < 0.001 |
 Lym (1000 cell/ul) | 1.92 (0.02) | 1.92 (0.02) | 1.92 (0.05) | 0.966 |
 Mono (1000 cell/ul) | 0.53 (0.01) | 0.52 (0.01) | 0.56 (0.01) | 0.004 |
 SII | 527.75 (8.13) | 517.70 (8.20) | 601.61 (19.63) |  < 0.001 |
 NLR | 2.17 (0.03) | 2.12 (0.03) | 2.49 (0.07) |  < 0.001 |
 MLR | 0.29 (0.00) | 0.29 (0.00) | 0.32 (0.01) |  < 0.001 |
 PLR | 136.50 (1.39) | 136.20 (1.45) | 138.76 (2.28) | 0.269 |
 SIRI | 1.17 (0.02) | 1.14 (0.02) | 1.43 (0.05) |  < 0.001 |
 PIV | 288.06 (5.47) | 279.62 (5.64) | 350.07 (15.86) |  < 0.001 |
Biomarkers of renal function | ||||
 eGFR (mL/min/1.73m2) | 89.44 (0.35) | 91.59 (0.31) | 74.72 (0.90) |  < 0.001 |
 Serum creatinine (mg/dl) | 0.87 (0.00) | 0.84 (0.00) | 1.08 (0.02) |  < 0.001 |
 UACR (mg/g) | 16.09 (0.14) | 16.09 (0.14) | 16.10 (0.22) | 0.937 |
 Uric acid (mg/dl) | 5.40 (0.03) | 5.33 (0.03) | 5.94 (0.06) |  < 0.001 |
 Serum urea nitrogen (mg/dl) | 13.58 (0.10) | 13.19 (0.09) | 16.25 (0.25) |  < 0.001 |