Table 2.

RRs and 95% CIs of NHL according to annual number of sunburns in successive decades of life

Age period and no. of sunburnsNo. of casesAge-adjustedMultivariate*
RR (95% CI)RR (95% CI)
<10 y (n = 44,932)
    0451.001.00
    ≥1/y540.87 (0.59-1.29)0.96 (0.63-1.45)
P = 0.49P = 0.84
10-19 y (n = 92,451)
    0341.001.00
    ≤1/y801.01 (0.68-1.51)1.10 (0.72-1.67)
    ≥2/y250.84 (0.50-1.42)1.12 (0.64-1.95)
Ptrend = 0.55Ptrend = 0.69
20-29 y (n = 94,355)
    0391.001.00
    ≤1/y820.76 (0.52-1.12)0.85 (0.57-1.28)
    ≥2/y220.69 (0.41-1.16)0.91 (0.52-1.62)
Ptrend = 0.13Ptrend = 0.67
30-39 y (n = 91,858)
    0511.001.00
    ≤1/y810.88 (0.62-1.25)0.99 (0.68-1.43)
    ≥2/y110.66 (0.35-1.27)0.87 (0.44-1.72)
Ptrend = 0.21Ptrend = 0.75
40-49 y (n = 43,524)
    0401.001.00
    ≥1/y521.00 (0.67-1.52)1.17 (0.76-1.82)
P = 0.98P = 0.47
Combined, 10-39 y (n = 87,824)
    ≤1/y, 10-39 y1041.001.00
    ≥2/y, 10-39 y310.80 (0.54-1.20)0.99 (0.65-1.50)
P = 0.28P = 0.95

NOTE: Poisson regression analysis. All statistical tests were two-sided. Sunburns at age <10 years were only recorded for the Norwegian women. Analyses of sunburns at ages 40 to 49 years included only women ≥40 years when answering the questionnaire.

  • *Multivariate models included attained age, region of residence, eye color, hair color, and skin reaction after heavy sun exposure in the beginning of the summer and after repeated sun exposure.