Table 4.
Multivariate-adjusted odds ratios and 95% confidence intervals for arsenic in drinking water and bladder cancer, among ever- and never-smokers, Southeastern Michigan, Enrolled 2002–2006
| Ever smoker | Never smoker | |||||||
|---|---|---|---|---|---|---|---|---|
| Cases (no.) | Controls (no.) | OR | 95% CI | Cases (no.) | Controls (no.) | OR | 95% CI | |
| Arsenic concentration in water (TWA) | ||||||||
| Continuous (per 5 µg/L increase) | 311 | 306 | 0.95 | 0.81, 1.11 | 100 | 260 | 1.29 | 1.03, 1.63 |
| Categorical | ||||||||
| <1 µg/L | 136 | 139 | 1.00 | 52 | 125 | 1.00 | ||
| 1–10 µg/L | 148 | 144 | 0.96 | 0.68, 1.36 | 37 | 119 | 0.72 | 0.43, 1.20 |
| >10 µg/L | 27 | 23 | 0.94 | 0.50, 1.78 | 11 | 16 | 1.62 | 0.68, 3.87 |
| Arsenic intake from water (TWA)a | ||||||||
| Continuous (per 5 µg/day increase) | 303 | 295 | 0.97 | 0.86, 1.09 | 95 | 241 | 1.14 | 0.94, 1.37 |
| Categorical | ||||||||
| <1 µg/day | 139 | 128 | 1.00 | 51 | 126 | 1.00 | ||
| 1–10 µg/day | 133 | 135 | 0.88 | 0.62, 1.25 | 32 | 99 | 0.80 | 0.47, 1.35 |
| >10 µg/day | 31 | 32 | 0.74 | 0.41, 1.31 | 12 | 16 | 2.01 | 0.87, 4.68 |
Adjusted for education, history of employment in high-risk occupation, family history of bladder cancer, age, race, and sex
OR odds ratio; CI confidence interval; TWA time-weighted average
a
Differences in numbers of cases and controls for arsenic intake metric attributable to missing water consumption data