Table 2.

Relative risks of skin cancer according to quintilesa of cumulative UV flux in the Nurses' Health Study II (1989–2009)

Age-adjustedMV-adjusted
CasesRR (95% CI)RRb (95% CI)
BCC
 Quintile 16641.001.00
 Quintile 28291.40 (1.13–1.74)1.34 (1.09–1.66)
 Quintile 31,0821.75 (1.37–2.24)1.63 (1.27–2.08)
 Quintile 42,0232.09 (1.60–2.72)1.91 (1.46–2.48)
 Quintile 52,3572.64 (2.01–3.46)2.35 (1.79–3.07)
Ptrend<0.0001<0.0001
SCC
 Quintile 1451.001.00
 Quintile 2911.39 (0.70–2.78)1.37 (0.69–2.74)
 Quintile 31561.75 (0.80–3.82)1.71 (0.79–3.73)
 Quintile 42772.21 (0.98–4.99)2.16 (0.96–4.85)
 Quintile 53112.62 (1.15–5.99)2.53 (1.11–5.77)
Ptrend0.0030.009
Melanoma
 Quintile 1971.001.00
 Quintile 21590.75 (0.44–1.28)0.74 (0.44–1.25)
 Quintile 31490.64 (0.35–1.17)0.60 (0.33–1.09)
 Quintile 42180.81 (0.42–1.56)0.72 (0.37–1.38)
 Quintile 51560.79 (0.40–1.58)0.68 (0.34–1.34)
Ptrend0.980.38
  • aCumulative UV flux quintiles: Quintile 1 = 186–616, Quintile 2 = 617–1,078, Quintile 3 = 1,079–1,581, Quintile 4 = 1,582–2,034, and Quintile 5 = 2,035–3,920 × 104 Robertson–Berger units, respectively.

  • bMV-adjusted RR: multivariable analysis controlled for age, family history of melanoma, natural hair color, number of moles on legs, sunburn reaction as a child/adolescent, number of blistering sunburns between ages 15 and 20 years, average tanning bed use in early life, body mass index, alcohol intake, physical activity, smoking status, rotating night shifts, and menopausal status.