Table 3.
Hazard ratios (HR) and 95% confidence intervals (CI) of first primary basal cell carcinoma by average lifetime summer ambient temperature stratified by level of average lifetime summer ambient ultraviolet radiation (UVR), lagged by 20 years, in the U.S. Radiologic Technologists study1
UVR Quintile2 | Temperature range (0 F) | No. cases | HR | 95% CI | P-trend |
---|---|---|---|---|---|
|
|||||
Q1 | 46.3–69.0 | 372 | Ref | ||
69.0–71.2 | 189 | 1.12 | 0.93–1.35 | ||
71.2–93.6 | 39 | 1.22 | 0.87–1.70 | 0.13 | |
Q2 | 46.3–69.0 | 84 | Ref | ||
69.0–71.2 | 274 | 1.16 | 0.90–1.48 | ||
71.2–73.3 | 243 | 1.09 | 0.84–1.40 | ||
73.3–93.6 | 53 | 1.19 | 0.84–1.69 | 0.60 | |
Q3 | 46.3–71.2 | 118 | Ref | ||
71.2–73.3 | 224 | 1.01 | 0.80–1.26 | ||
73.3–93.6 | 321 | 1.21 | 0.98–1.50 | 0.03 | |
Q4 | 46.3–71.2 | 96 | Ref | ||
71.2–73.3 | 73 | 1.18 | 0.87–1.60 | ||
73.3–76.6 | 286 | 1.18 | 0.93–1.60 | ||
76.6–93.6 | 289 | 1.16 | 0.93–1.50 | 0.28 | |
Q5 | 46.3–69.0 | 102 | Ref | ||
69.0–71.2 | 75 | 1.26 | 0.93–1.69 | ||
71.2–73.3 | 114 | 1.50 | 1.15–1.97 | ||
73.3–76.6 | 136 | 1.24 | 0.96–1.61 | ||
76.6–93.6 | 468 | 1.13 | 0.91–1.41 | 0.94 |
HR adjusted for sex, BMI (<25;25-<30; ≥30 kg/m2;missing), eye color (categories), average lifetime summer time outdoors (quintiles) and average lifetime UVR (continuous) with the baseline hazard stratified on birth cohort (5-year categories). P-trend based on continuous ordinal values.
The analysis was based on quintiles of temperature. When there were <50 BCC cases in a quintile, quintiles were combined. Quintiles of temperature, which had uniform cut-points, were combined as follows: in UVR quintile 1, we combined temperature Q3–Q5; in UVR quintile 2, we combined temperature Q4–Q5; in UVR quintile 3, we combined Q1–Q2 and Q4–Q5; in UVR quintile 4, we combined temperature Q1–Q2; and in UVR quintile 5, all temperature quintiles were presented.