Table 1.
Baseline characteristics of participants in NHANES (N = 11,282).
| Variables | Total Participants | Dietary Fiber Intake (g/Day) | ||||
|---|---|---|---|---|---|---|
| Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 | p Value | ||
| Age, years, mean (SD) | 57.8 (10.8) | 57.6 (10.8) | 58.2 (11.0) | 57.8 (10.9) | 57.5 (10.5) | 0.059 |
| BMI, kg/m2, mean (SD) | 29.9 (6.7) | 30.3 (7.3) | 30.1 (6.8) | 29.7 (6.4) | 29.4 (6.4) | <0.001 |
| PIR, mean (SD) | 2.7 (1.7) | 2.3 (1.6) | 2.6 (1.6) | 2.8 (1.7) | 2.9 (1.7) | <0.001 |
| Sex, n (%) | <0.001 | |||||
| male | 5544 (49.1) | 1141 (40.7) | 1254 (44.4) | 1410 (49.8) | 1739 (61.6) | |
| female | 5738 (50.9) | 1663 (59.3) | 1571 (55.6) | 1421 (50.2) | 1083 (38.4) | |
| Educational attainment, n (%) | <0.001 | |||||
| <High school | 2950 (26.1) | 883 (31.5) | 682 (24.1) | 681 (24.1) | 704 (24.9) | |
| High school | 2519 (22.3) | 716 (25.5) | 731 (25.9) | 587 (20.7) | 485 (17.2) | |
| College or above | 5813 (51.5) | 1205 (43.0) | 1412 (50.0) | 1563 (55.2) | 1633 (57.9) | |
| Race/Ethnicity, n (%) | <0.001 | |||||
| Non-Hispanic white | 5203 (46.1) | 1263 (45.0) | 1372 (48.6) | 1331 (47.0) | 1237 (43.8) | |
| Non-Hispanic black | 2234 (19.8) | 760 (27.1) | 608 (21.5) | 463 (16.4) | 403 (14.3) | |
| Other Hispanic | 1199 (10.6) | 300 (10.7) | 316 (11.2) | 320 (11.3) | 263 (9.3) | |
| Mexican American or other | 2646 (23.5) | 481 (17.2) | 529 (18.7) | 717 (25.3) | 919 (32.6) | |
| Serum cotinine, ng/mL, median (25th–75th) | 0.0 (0.0–2.5) | 0.1 (0.0–179.0) | 0.0 (0.0–1.7) | 0.0 (0.0–0.3) | 0.0 (0.0–0.1) | <0.001 |
| Alcohol drinking, n (%) | <0.001 | |||||
| More than 12 drinks/yr | 3199 (28.4) | 864 (30.8) | 853 (30.2) | 778 (27.5) | 704 (24.9) | |
| Less than 12 drinks/yr | 8083 (71.6) | 1940 (69.2) | 1972 (69.8) | 2053 (72.5) | 2118 (75.1) | |
| Diabetes, n (%) | 0.002 | |||||
| no | 8569 (76.0) | 2076 (74.0) | 2118 (75.0) | 2173 (76.8) | 2202 (78.0) | |
| yes | 2713 (24.0) | 728 (26.0) | 707 (25.0) | 658 (23.2) | 620 (22.0) | |
| Hypertension, n (%) | <0.001 | |||||
| no | 5133 (45.5) | 1155 (41.2) | 1216 (43.0) | 1337 (47.2) | 1425 (50.5) | |
| yes | 6149 (54.5) | 1649 (58.8) | 1609 (57.0) | 1494 (52.8) | 1397 (49.5) | |
| eGFR, mL/min/1.73 m2, mean (SD) | 84.0 (19.6) | 82.2 (21.0) | 83.0 (20.1) | 84.5 (19.0) | 86.4 (18.2) | <0.001 |
| Dietary energy intake, kcal/day, mean (SD) | 2023.7 (914.1) | 1431.4 (619.2) | 1864.0 (713.7) | 2139.3 (759.5) | 2655.9 (1041.1) | <0.001 |
| Serum Klotho, pg/mL, median (25th–75th) | 800.6 (653.9–990.0) | 783.8 (631.2–977.4) | 800.5 (657.3–987.1) | 805.6 (659.2–991.9) | 810.9 (662.0–1002.6) | 0.002 |
Note: SD, standard deviation; BMI, body mass index; PIR, family poverty income ratio; eGFR, estimated glomerular filtration rate. Dietary fiber intake quartile ranges: Quartile 1 = 0.0 to 9.6 g/day; Quartile 2 = 9.7 to 14.8 g/day; Quartile 3 = 14.9 to 21.7 g/day; Quartile 4: 21.8 to 113.9 g/day.