Table 4.
Hazard Ratios and 95% Confidence Intervals for the Association of Thyroid Cancer With Anthropometric Factors, Smoking, and Alcohol Intake, US Radiologic Technologists Study, 1983–2006
| Women |
Men |
|||||
| No. of Casesa | HRb | 95% CI | No. of Casesa | HRb | 95% CI | |
| Height quartilec | ||||||
| 1 | 70 | 1.00 | Reference | 13 | 1.00 | Reference |
| 2 | 47 | 1.08 | 0.74, 1.56 | 13 | 1.08 | 0.50, 2.33 |
| 3 | 66 | 1.19 | 0.85, 1.67 | 9 | 0.73 | 0.31, 1.71 |
| 4 | 58 | 1.10 | 0.78, 1.56 | 5 | 0.58 | 0.20, 1.63 |
| P-trend* | 0.46 | 0.22 | ||||
| Weight quartiled,e | ||||||
| 1 | 52 | 1.00 | Reference | 10 | 1.00 | Reference |
| 2 | 47 | 1.00 | 0.67, 1.49 | 10 | 1.21 | 0.49, 2.96 |
| 3 | 69 | 1.26 | 0.86, 1.84 | 6 | 0.70 | 0.24, 2.01 |
| 4 | 68 | 1.43 | 0.97, 2.11 | 14 | 1.81 | 0.73, 4.50 |
| P-trend* | 0.04 | 0.33 | ||||
| Body mass index, kg/m2 | ||||||
| <18.5 | 6 | 0.96 | 0.42, 2.18 | 0 | ||
| 18.5–24.9 | 144 | 1.00 | Reference | 13 | 1.00 | Reference |
| 25.0–29.9 | 44 | 0.90 | 0.64, 1.27 | 15 | 0.89 | 0.42, 1.90 |
| 30.0–34.9 | 26 | 1.41 | 0.92, 2.16 | 9 | 1.91 | 0.80, 4.56 |
| ≥35.0 | 16 | 1.74 | 1.03, 2.94 | 3 | 2.14 | 0.60, 7.67 |
| P-trend* | 0.04 | 0.11 | ||||
| Smoking status | ||||||
| Never smoker | 147 | 1.00 | Reference | 21 | 1.00 | Reference |
| Former smoker | 64 | 0.91 | 0.67, 1.22 | 13 | 0.79 | 0.39, 1.61 |
| Current smoker | 26 | 0.54 | 0.35, 0.82 | 3 | 0.31 | 0.09, 1.04 |
| Smoking intensity | ||||||
| Former, <20 cigarettes/day | 48 | 0.99 | 0.71, 1.37 | 8 | 0.96 | 0.42, 2.21 |
| Former, ≥20 cigarettes/day | 15 | 0.69 | 0.40, 1.18 | 4 | 0.50 | 0.17, 1.51 |
| Current, <20 cigarettes/day | 19 | 0.64 | 0.40, 1.04 | 2 | 0.43 | 0.10, 1.86 |
| Current, ≥20 cigarettes/day | 7 | 0.38 | 0.18, 0.82 | 1 | 0.20 | 0.03, 1.49 |
| Alcohol intake | ||||||
| Nondrinker | 57 | 1.00 | Reference | 10 | 1.00 | Reference |
| <1 drink/week | 95 | 0.86 | 0.62, 1.20 | 13 | 1.03 | 0.45, 2.38 |
| 1–6 drinks/week | 66 | 0.86 | 0.60, 1.23 | 9 | 0.62 | 0.25, 1.54 |
| ≥7 drinks/week | 18 | 0.84 | 0.49, 1.45 | 7 | 0.95 | 0.35, 2.54 |
| P-trend* | 0.45 | 0.50 | ||||
Abbreviations: CI, confidence interval; HR, hazard ratio.
*P-trend based on ordinal score variable.
Number of cases may be inconsistent because of missing values.
Adjusted for birth year, smoking status, body mass index, number of personal radiographs to the head or neck, cumulative occupational radiation dose, and medical history of benign thyroid conditions.
Height quartiles (cm)—women: <161, 161–164, 165–167, ≥168; men: <173, 173–178, 179–183, ≥184.
Weight quartiles (kg)—women: <54.5, 54.5–60.9, 61.0–68.1, ≥68.2; men: <73.0, 73.0–79.9, 80.0–88.5, ≥88.6.
Also adjusted for height.