Table 3.
Odds Ratio (95% CI) of Hypertension by Urine Arsenic Concentrations
| Quartile
| ||||||
|---|---|---|---|---|---|---|
| Per doubling of arsenic | 1a | 2 | 3 | 4 | Test for Trendb | |
| OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | ||
| Total arsenic (μg/L) | ||||||
| <4.2 | 4.2 to 8.3 | >8.3 to 17.1 | >17.1 | |||
| No. | (n=1761/2406)c | (n=418/534) c | (n=451/606) c | (n=446/644) c | (n=446/622) c | |
| Crude | 0.98 (0.94 to 1.03) | 1.00 | 0.98 (0.79 to 1.21) | 1.06 (0.85 to 1.32) | 0.94 (0.76 to 1.17) | P =0.39 |
| Model 1d | 0.99 (0.93 to 1.06) | 1.00 | 1.08 (0.84 to 1.38) | 1.18 (0.88 to 1.57) | 1.04 (0.77 to 1.40) | P =0.79 |
| Model 2e | 1.03 (0.96 to 1.10) | 1.00 | 1.09 (0.84 to 1.41) | 1.33 (0.99 to 1.80) | 1.22 (0.91 to 1.64) | P =0.45 |
| Model 3f | 0.98 (0.86 to 1.11) | 1.00 | 1.08 (0.83 to 1.40) | 1.30 (0.94 to 1.80) | 1.17 (0.75 to 1.83) | P =0.71 |
| Total arsenic minus arsenobetaine (μg/L) | ||||||
| <3.1 | 3.1 to 5.8 | >5.8 to 10.8 | >10.8 | |||
| No. | (n=1761/2406) c | (n=426/489) c | (n=428/605) c | (n=463/636) c | (n=432/670) c | |
| Crude | 0.96 (0.92 to 1.01) | 1.00 | 0.89 (0.72 to 1.10) | 0.96 (0.77 to 1.20) | 0.83 (0.68 to 1.00) | P =0.11 |
| Model 1d | 0.99 (0.92 to 1.08) | 1.00 | 0.97 (0.74 to 1.28) | 1.14 (0.83 to 1.56) | 1.04 (0.74 to 1.45) | P =0.89 |
| Model 2e | 1.05 (0.96 to 1.14) | 1.00 | 1.07 (0.81 to 1.42) | 1.34 (0.95 to 1.89) | 1.30 (0.92 to 1.83) | P =0.28 |
| Model 3f | 1.03 (0.94 to 1.14) | 1.00 | 1.07 (0.81 to 1.40) | 1.33 (0.95 to 1.85) | 1.27 (0.88 to 1.83) | P =0.53 |
| Dimethylarsinate (μg/L) | ||||||
| <2.0 | 2.0 to 3.6 | >3.6 to 6.0 | >6.0 | |||
| No. | (n=1761/2406) c | (n=415/496) c | (n=461/613) c | (n=448/631) c | (n=437/666) c | |
| Crude | 0.96 (0.90 to 1.02) | 1.00 | 0.95 (0.78 to 1.17) | 0.92 (0.73 to 1.16) | 0.88 (0.72 to 1.08) | P =0.18 |
| Model 1d | 1.03 (0.93 to 1.14) | 1.00 | 0.96 (0.73 to 1.28) | 1.04 (0.76 to 1.40) | 1.05 (0.75 to 1.46) | P =0.55 |
| Model 2e | 1.12 (1.01 to 1.23) | 1.00 | 1.06 (0.80 to 1.41) | 1.21 (0.89 to 1.64) | 1.29 (0.93 to 1.79) | P =0.03 |
| Model 3f | 1.11 (0.99 to 1.24) | 1.00 | 1.05 (0.77 to 1.42) | 1.18 (0.84 to 1.66) | 1.24 (0.84 to 1.83) | P =0.07 |
a
Reference category
b
Based on log-transformed arsenic concentrations
c
No. with/without hypertension
d
Adjusted for sex, age, race and ethnicity, and urine creatinine level (log-transformed)
e
further adjusted for education, body mass index, serum cotinine level (log-transformed)
f
further adjusted for arsenobetaine (log-transformed)