Table 1.
Characteristics of subjects at three consecutive examinations.
| 1985–1989
|
1991–1996
|
2001–2003
|
||||
|---|---|---|---|---|---|---|
| Characteristic | LEA | HEA | LEA | HEA | LEA | HEA |
| No. | 476 | 480 | 369 | 367 | 258 | 203 |
| Women [no. (%)] | 260 (54.6) | 265 (55.1) | 201 (54.5) | 206 (56.1) | 142 (55.3) | 111 (54.7) |
| Age [years (mean ± SD)] | 46. 9 ± 15.4 | 47.3 ± 15.5 | 50.0 ± 14.1 | 49.6 ± 14.5 | 57.1 ± 13.5 | 55.2 ± 13.2 |
| Body mass index [kg/m2 (mean ± SD)] | 25.7 ± 4.2 | 26.1 ± 4.6 | 26.0 ± 4.3 | 26.5 ± 5.1 | 26.6 ± 4.2 | 27.1 ± 5.1 |
| Systolic pressure [mmHg (mean ± SD)] | 129 ± 18 | 128 ± 16 | 126 ± 18 | 129 ± 19 | 128 ± 18 | 127 ± 16 |
| Diastolic pressure [mmHg (mean ± SD)] | 75 ± 9 | 76 ± 9 | 78 ± 10 | 79 ± 11 | 77 ± 10 | 77 ± 10 |
| Distance to nearest smelter [km; GM (IQR)] | 10.8 (9.1–12.7) | 1.2 (0.7–1.6)## | 10.8 (9.1–12.7) | 1.1 (0.7–1.6)## | 10.7 (9.0–12.7) | 1.2 (0.7–1.6)## |
| Smokers [no. (%)] | 177 (37.0) | 186 (39.0) | 110 (29.8) | 124 (33.8) | 94 (36.4) | 83 (40.9)** |
| Alcohol drinkers [no. (%)] | 80 (17.4) | 88 (18.5) | 76 (20.6) | 71 (19.4) | 2 (0.8) | 0 (0) |
| Serum total cholesterol [mmol/L (mean ± SD)] | 6.02 ± 1.41 | 5.84 ± 1.37 | 5.68 ± 1.09 | 5.80 ± 1.10 | 5.66 ± 0.99 | 5.39 ± 0.98# |
| Serum HDL cholesterol [mmol/L (mean ± SD)] | 1.42 ± 0.43 | 1.13 ± 0.36 | 1.33 ± 0.37 | 1.29 ± 0.36 | 1.46 ± 0.42 | 1.40 ± 0.38 |
| Serum creatinine [μmol/L (mean ± SD)] | 98 ± 24 | 101 ± 18 | 92 ± 21 | 89 ± 18 | 88 ± 17 | 90 ± 17 |
| Serum γ-glutamyltransferase [U/L; GM (IQR)] | 36 (22–48) | 34.4 (22–48) | 25 (15–35) | 29 (19–41) | 21 (14–28) | 22 (15–29) |
| Serum ferritin [pmol/L; GM (IQR)] | 234 (126–444) | 262 (141–510) | — | — | — | — |
| BCd [nmol/L; GM (IQR)] | 10.6 (7.1–16.9) | 11.5 (6.8–19.6)* | 6.3 (4.4–10.7) | 8.8 (5.3–16.0)## | 7.4 (5.1–11.1) | 8.2 (5.3–13.7)* |
| UCd [nmol/day; GM (IQR)] | 7.7 (5.4–11.9) | 11.7 (6.8–19.5)## | 6.7 (4.4–10.4) | 9.1 (5.7–14.9)## | — | — |
| Urinary RBP [μg/day; GM (IQR)] | 123 (84–173) | 136 (94–196)** | 68 (46–104) | 73 (49–101) | — | — |
| Urinary creatinine [mmol/day (mean ± SD)] | 12.2 ± 3.9 | 12.4 ± 4.3 | 11.8 ± 4.0 | 11.3 ± 3.7 | — | — |
Abbreviations: —, no data; GM, geometric mean. Serum ferritin was measured only at baseline. Participants did not collect a 24-hr urine sample in 2001–2003. Significance of the difference between LEA and HEA:
*
0.10 ≤ p < 0.05;
**
p ≤ 0.05;
#
p ≤ 0.01;
##
p ≤ 0.001.