Table 2.
Associations between cell phone use and risk of thyroid cancer
| Overall |
Male |
Female |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Cell phone user | Control | Case | OR (95% CI)a |
P for trend |
Case | OR (95% CI)a |
P for trend |
Case | OR (95% CI)a |
P for trend |
| No | 122 | 102 | 1.00 | 18 | 1.00 | 84 | 1.00 | |||
| Yes | 376 | 360 | 1.05 (0.74, 1.48) | 69 | 1.27 (0.62, 2.61) | 291 | 0.99 (0.66, 1.47) | |||
| Hands-free device | ||||||||||
| Yes | 10 | 9 | 1.15 (0.43, 3.08) | 1 | 1.27 (0.62, 2.62) | 8 | 0.98 (0.65, 1.47) | |||
| No | 366 | 351 | 1.05 (0.74, 1.48) | 68 | 1.18 (0.06, 22.46) | 283 | 1.16 (0.40, 3.37) | |||
| Daily use hour | 0.102 | 0.913 | 0.082 | |||||||
| ≤1 hours/day | 137 | 124 | 1.10 (0.72, 1.66) | 25 | 1.76 (0.72, 4.32) | 99 | 0.97 (0.60, 1.56) | |||
| 1–2 hours/day | 47 | 60 | 1.51 (0.90, 2.53) | 13 | 1.66 (0.57, 4.82) | 47 | 1.45 (0.79, 2.65) | |||
| >2 hours/day | 52 | 61 | 1.40 (0.83, 2.35) | 12 | 1.05 (0.35, 3.14) | 49 | 1.52 (0.83, 2.80) | |||
| Daily phone call | 0.392 | 0.307 | 0.728 | |||||||
| ≤3 calls/day | 141 | 122 | 0.95 (0.63, 1.42) | 14 | 0.68 (0.27, 1.73) | 108 | 1.01 (0.64, 1.59) | |||
| 3–6 calls/day | 112 | 99 | 0.98 (0.63, 1.50) | 23 | 1.57 (0.65, 3.78) | 76 | 0.84 (0.51, 1.38) | |||
| >6 calls/day | 105 | 113 | 1.19 (0.77, 1.84) | 26 | 1.22 (0.51, 2.92) | 87 | 1.17 (0.70, 1.94) | |||
| Phone use year | 0.337 | 0.101 | 0.910 | |||||||
| ≤12 years | 138 | 128 | 0.99 (0.66, 1.49) | 17 | 0.99 (0.39, 2.48) | 111 | 0.97 (0.61, 1.53) | |||
| 12–15 years | 143 | 129 | 0.94 (0.63, 1.42) | 19 | 0.82 (0.34, 1.97) | 110 | 0.97 (0.61, 1.55) | |||
| >15 years | 92 | 99 | 1.29 (0.83, 2.00) | 31 | 2.11 (0.91, 4.89) | 68 | 1.03 (0.62, 1.73) | |||
| Age at first use | 0.828 | 0.680 | 0.992 | |||||||
| ≤20 years old | 34 | 47 | 1.08 (0.53, 2.20) | 9 | 1.49 (0.34, 6.01) | 38 | 0.95 (0.42, 2.18) | |||
| 21–50 years old | 267 | 260 | 1.06 (0.72, 1.55) | 48 | 1.44 (0.65, 3.17) | 212 | 0.96 (0.62, 1.49) | |||
| >50 years old | 75 | 53 | 1.03 (0.62, 1.70) | 12 | 0.99 (0.36, 2.70) | 41 | 1.05 (0.58, 1.90) | |||
| Cumulative use hour | 0.072 | 0.493 | 0.094 | |||||||
| ≤4,745 hours | 92 | 85 | 1.10 (0.70, 1.74) | 14 | 1.91 (0.68, 5.38) | 71 | 0.98 (0.58, 1.63) | |||
| 4,745–9,490 hours | 75 | 72 | 1.13 (0.71, 1.82) | 14 | 1.31 (0.46, 3.72) | 58 | 1.08 (0.63, 1.85) | |||
| >9,490 hours | 68 | 87 | 1.58 (0.98, 2.54) | 21 | 1.55 (0.61, 3.96) | 66 | 1.63 (0.93, 2.86) | |||
| Cumulative phone call | 0.535 | 0.141 | 0.843 | |||||||
| ≤14,235 calls | 131 | 119 | 1.01 (0.67, 1.52) | 11 | 0.69 (0.25, 1.86) | 108 | 1.06 (0.67, 1.67) | |||
| 14,235–32,850 calls | 116 | 98 | 0.87 (0.56, 1.35) | 16 | 0.86 (0.34, 2.19) | 82 | 0.86 (0.52, 1.42) | |||
| >32,850 calls | 108 | 114 | 1.20 (0.78, 1.84) | 34 | 1.65 (0.71, 3.81) | 80 | 1.02 (0.61, 1.70) | |||
CI, confidence interval; OR, odds ratio
a
Adjusted for age (continuous), sex (male, female), education (<college, college, >college), family history of thyroid cancer (yes, no), alcohol consumption (yes, no), BMI (<25, 25–29.9, ≥30 kg/m2), previous benign thyroid disease (yes, no), occupational radiation exposure (yes, no), and radiation treatment (yes, no).