Table 1B.
Demographic and health characteristics of overall study cohort and according to nitrogen dioxide (NO2) level.
| NO2 Level (ppb) | |||||
|---|---|---|---|---|---|
| Total (N = 6,480) |
Tertile 1: <12.88 (N = 2,165) |
Tertile 2: 12.88–15.00 (N = 2,518) |
Tertile 3: ≥15.00 (N = 2,157) |
p values a | |
| eGFR stage 3b, 4, 5 | 2,901/ 2,175/ 1,404 | 966/ 717/ 482 | 1,020/ 715/ 423 | 915/ 743 / 499 | <0.0001 |
| Incident N (%) of eGFR deterioration | 3,100 (47.84%) | 905 (41.80) | 977 (45.27) | 1,218 (56.47) | <0.0001 |
| Follow-up time | 2.32 ± 2.88 | 2.04 ± 2.55 | 2.86 ± 3.27 | 2.06 ± 2.70 | <0.0001 |
| Ageb | 75.31 ± 14.84 | 72.22 ± 14.21 | 74.85 ± 14.70 | 78.86 ± 14.86 | <0.0001 |
| Female (%)b | 2,494 (38.49) | 852 (39.35) | 868 (40.22) | 774 (35.88) | |
| County | <0.0001 | ||||
| Taichung | 5,292 (81.67) | 1,522 (70.30) | 1,831 (84.85) | 1,939 (89.89) | |
| Nantou | 537 (8.29) | 366 (16.91) | 98 (4.54) | 73 (3.38) | |
| Changhua | 651 (10.05) | 277 (12.79) | 229 (10.61) | 145 (6.72) | |
| Education | <0.0001 | ||||
| Elementary school or below | 3,091 (47.72) | 1,054 (48.68) | 960 (44.49) | 1,077 (49.98) | |
| High school | 2,125 (32.80) | 762 (35.20) | 741 (34.34) | 622 (28.86) | |
| College or above | 1,262 (19.48) | 349 (16.12) | 457 (21.18) | 456 (21.16) | |
| Occupation | <0.0001 | ||||
| No | 1,623 (25.06) | 433 (20.01) | 540 (25.02) | 650 (30.16) | |
| Yes | 1,201 (18.54) | 488 (22.55) | 408 (18.91) | 305 (14.15) | |
| Other | 3,653 (56.40) | 1,243 (57.44) | 1,210 (56.07) | 1,200 (55.68) | |
| Smoking status | 0.0505 | ||||
| No | 4,141 (63.93) | 1,394 (64.42) | 1,415 (65.57) | 1,332 (61.81) | |
| Yes | 638 (9.85) | 195 (9.01) | 215 (9.96) | 228 (10.58) | |
| Quit | 1,698 (26.22) | 575 (26.57) | 528 (24.47) | 595 (27.61) | |
| Sports habits | 0.9571 | ||||
| No | 3,182 (49.12) | 1,069 (49.38) | 1,058 (49.03) | 1,055 (48.96) | |
| Yes | 3,296 (50.88) | 1,096 (50.62) | 1,100 (50.97) | 1,100 (51.04) | |
| Comorbidities | |||||
| Diabetes mellitus | 2,743 (42.34) | 944 (43.60) | 924 (42.82) | 875 (40.60) | 0.1178 |
| Hypertension | 4,829 (74.54) | 1,542 (71.22) | 1,625 (75.30) | 1,662 (77.12) | <0.0001 |
| Gout | 1,255 (19.37) | 412 (19.03) | 421 (19.51) | 422 (19.58) | 0.8829 |
| Medication usages | |||||
| EPO | 2,235 (34.86) | 675 (31.34) | 755 (35.17) | 805 (38.15) | <0.0001 |
| Pressure pills | 5,617 (87.62) | 1,790 (83.10) | 1,925 (89.66) | 1,902 (90.14) | <0.0001 |
| ACEI | 604 (9.42) | 111 (5.15) | 188 (8.76) | 305 (14.45) | <0.0001 |
| CCB | 3,990 (62.24) | 1,299 (60.31) | 1,370 (63.81) | 1,321 (62.61) | 0.0551 |
| Diuretics | 2,938 (45.83) | 872 (40.48) | 1,028 (47.88) | 1,038 (49.19) | <0.0001 |
| Iron supplement | 1,232 (19.22) | 365 (16.95) | 424 (19.75%) | 443 (21.00) | 0.0027 |
| Calcium phosphate binders | 1,625 (25.35) | 434 (20.15) | 565 (26.32) | 626 (29.67) | <0.0001 |
| Antidiabetic drugs | 2,655 (41.41) | 900 (41.78) | 909 (42.34) | 846 (40.09) | 0.3027 |
| Biochemical examination | |||||
| SBP (mmHg) | 133.31 ± 17.62 | 132.93 ± 17.95 | 133.40 ± 17.42 | 133.64 ± 17.48 | 0.6111 |
| DBP (mmHg) | 74.34 ± 11.00 | 74.13 ± 11.28 | 74.88 ± 10.89 | 73.97 ± 10.79 | 0.0309 |
| Hemoglobin | 11.19 ± 2.19 | 11.22 ± 2.20 | 11.24 ± 2.10 | 11.09 ± 2.30 | 0.0534 |
| Hematocrit | 26.08 ± 14.71 | 19.59 ± 17.08 | 25.73 ± 15.05 | 32.29 ± 7.87 | <0.0001 |
| Urea Nitrogen | 41.46 ± 22.15 | 41.31 ± 22.87 | 40.34 ± 21.42 | 42.74 ± 22.07 | <0.0001 |
| Albumin | 3.99 ± 1.35 | 4.02 ± 2.21 | 3.98 ± 0.53 | 3.96 ± 0.51 | 0.0059 |
| Cholesterol (mg/dL) | 180.11 ± 47.78 | 174.27 ± 47.92 | 179.89 ± 47.28 | 184.94 ± 47.63 | <0.0001 |
| HbA1c | 6.78 ± 3.41 | 6.79 ± 4.90 | 6.67 ± 1.48 | 6.90 ± 2.73 | 0.0224 |
| Urine PCR | 1,629.12 ± 2,627.20 | 1,729.23 ± 2,813.60 | 1,566.66 ± 2,633.40 | 1,576.52 ± 2,349.70 | 0.0015 |
a
p values were calculated by Chi-squares or Kruskal-Wallis test depending on categorical or continuums variables.
b
Continuous variables were presented as mean±SD and categorical variables were presented as n (%).