Table 1.
Baseline characteristics of the study participants.
| Variables | Overall | Serum Klotho quartiles (pg/mL) | P value | |||
|---|---|---|---|---|---|---|
| Q1 | Q2 | Q3 | Q4 | |||
| Participants (n) | 13751 | 3438 | 3438 | 3437 | 3438 | |
| Age (years) | 57.74 (10.86) | 59.14 (11.09) | 57.97 (10.83) | 57.39 (10.74) | 56.45 (10.59) | <0.001 |
| Sex (n, %) | <0.001 | |||||
| Female | 7085 (51.5) | 1661 (48.3) | 1659 (48.3) | 1809 (52.6) | 1956 (56.9) | |
| Male | 6666 (48.5) | 1777 (51.7) | 1779 (51.7) | 1628 (47.4) | 1482 (43.1) | |
| Education (n, %) | 0.003 | |||||
| Below high school | 1874 (13.6) | 480 (14.0) | 474 (13.8) | 472 (13.7) | 448 (13.0) | |
| High school | 5059 (36.8) | 1354 (39.4) | 1240 (36.1) | 1248 (36.3) | 1217 (35.4) | |
| Above high school | 6810 (49.6) | 1600 (46.6) | 1723 (50.1) | 1714 (49.9) | 1773 (51.6) | |
| Race, (n, %) | <0.001 | |||||
| Mexican American | 2186 (15.9) | 557 (16.2) | 539 (15.7) | 560 (16.3) | 530 (15.4) | |
| Non-Hispanic Black | 2723 (19.8) | 698 (20.3) | 567 (16.5) | 585 (17.0) | 873 (25.4) | |
| Non-Hispanic White | 5918 (43.0) | 1554 (45.2) | 1591 (46.3) | 1503 (43.7) | 1270 (36.9) | |
| Other Hispanic | 1575 (11.5) | 345 (10.0) | 384 (11.2) | 409 (11.9) | 437 (12.7) | |
| Other Race | 1349 (9.8) | 284 (8.3) | 357 (10.4) | 380 (11.1) | 328 (9.5) | |
| BMI (kg/m2) | 29.74 (6.71) | 29.87 (6.40) | 29.75 (6.64) | 29.64 (6.73) | 29.68 (7.05) | 0.506 |
| Waist (cm) | 101.76 (15.49) | 102.89 (15.03) | 102.17 (15.45) | 101.29 (15.37) | 100.71 (16.01) | <0.001 |
| Triglyceride (mmol/l) | 1.24 (0.87, 1.82) | 1.30 (0.91, 1.91) | 1.28 (0.91, 1.86) | 1.24 (0.87, 1.78) | 1.15 (0.81, 1.69) | <0.001 |
| Total Cholesterol (mmol/l) | 5.14 (1.10) | 5.14 (1.17) | 5.15 (1.09) | 5.14 (1.05) | 5.13 (1.10) | 0.906 |
| LDL-C (mmol/l) | 3.04 (0.93) | 2.98 (0.97) | 3.08 (0.93) | 3.06 (0.93) | 3.04 (0.91) | 0.035 |
| HDL-C (mmol/l) | 1.37 (0.43) | 1.37 (0.44) | 1.36 (0.43) | 1.38 (0.43) | 1.39 (0.44) | 0.011 |
| Creatinine (umol/l) | 75.14 (63.65, 90.17) | 80.44 (65.64, 96.36) | 76.91 (64.53, 90.17) | 74.26 (63.65, 88.40) | 72.49 (61.88, 85.75) | <0.001 |
| Klotho (pg/mL) | 802.50 (654.75, 993.25) | 556.70 (489.75, 610.70) | 727.50 (690.82, 763.50) | 886.80 (841.60, 935.30) | 1171.60 (1070.12, 1341.68) | <0.001 |
| Smoke (n, %) | <0.001 | |||||
| Never | 7064 (51.4) | 1571 (45.7) | 1701 (49.5) | 1827 (53.2) | 1965 (57.2) | |
| Former | 3984 (29.0) | 1091 (31.8) | 1035 (30.1) | 975 (28.4) | 883 (25.7) | |
| Now | 2696 (19.6) | 772 (22.5) | 701 (20.4) | 634 (18.5) | 589 (17.1) | |
| Alcohol intake (n, %) | <0.001 | |||||
| Yes | 9013 (70.7) | 2417 (74.9) | 2301 (72.1) | 2225 (70.1) | 2070 (65.4) | |
| No | 3740 (29.3) | 809 (25.1) | 891 (27.9) | 947 (29.9) | 1093 (34.6) | |
| CVD (n, %) | <0.001 | |||||
| Yes | 1904 (13.8) | 595 (17.3) | 471 (13.7) | 444 (12.9) | 394 (11.5) | |
| No | 11845 (86.2) | 2842 (82.7) | 2967 (86.3) | 2993 (87.1) | 3043 (88.5) | |
| Dyslipidemia (n, %) | <0.001 | |||||
| Yes | 11002 (80.0) | 2837 (82.5) | 2784 (81.0) | 2749 (80.0) | 2632 (76.6) | |
| No | 2749 (20.0) | 601 (17.5) | 654 (19.0) | 688 (20.0) | 806 (23.4) | |
| Hypertension (n, %) | <0.001 | |||||
| Yes | 7435 (54.1) | 2019 (58.7) | 1842 (53.6) | 1776 (51.7) | 1798 (52.3) | |
| No | 6316 (45.9) | 1419 (41.3) | 1596 (46.4) | 1661 (48.3) | 1640 (47.7) | |
| DM (n, %) | 0.010 | |||||
| Yes | 3557 (25.9) | 933 (27.1) | 842 (24.5) | 850 (24.7) | 932 (27.1) | |
| No | 10194 (74.1) | 2505 (72.9) | 2596 (75.5) | 2587 (75.3) | 2506 (72.9) | |
| Glycosylated hemoglobin (%) | 5.70 (5.40, 6.10) | 5.70 (5.40, 6.10) | 5.70 (5.40, 6.00) | 5.60 (5.40, 6.00) | 5.70 (5.40, 6.10) | 0.002 |
| eGFR (mL/min/1.73m2) | 86.67 (20.21) | 82.10 (22.68) | 86.09 (19.76) | 87.92 (18.43) | 90.58 (18.73) | <0.001 |
| Physical activity (never) (n, %) | 8582 (62.4) | 2094 (60.9) | 2118(61.6) | 2152 (62.6) | 2218(64.6) | 0.012 |
Data are shown as mean (SD), median (IQR), or n (%). Klotho was divided to four levels by quartile (Q1 ≤ 654.75; 654.75 < Q2 ≤ 802.50; 802.50 < Q3 ≤ 993.25; Q4 > 993.25). Abbreviations: BMI, body mass index; CVD, cardiovascular disease; DM, diabetes mellitus; LDL-C, Low-Density Lipoprotein Cholesterol; HDL-C, High density leptin cholesterol; eGFR, estimated glomerular filtration rate.