Table 2.

Use of tanning beds and cancer risk

Average use of tanning beds (4 times/y)aUse of tanning beds during high school/college (4 times/y)Use of tanning beds at ages 25 to 35 (4 times/y)
CancersCases (717,310 person-years)Age-adjusted HR (95% CI)Multivariable-adjusted HRb (95% CI)Age-adjusted HR (95% CI)Multivariable-adjusted HRb (95% CI)Age-adjusted HR (95% CI)Multivariable-adjusted HRb (95% CI)
Total cancer4,2710.99 (0.95–1.04)0.99 (0.95–1.04)1.02 (0.97–1.07)1.02 (0.97–1.07)0.99 (0.96–1.02)0.99 (0.96–1.02)
Breast cancer2,7791.00 (0.94–1.06)0.99 (0.94–1.06)c1.04 (0.99–1.10)1.03 (0.98–1.09)c0.98 (0.94–1.02)0.98 (0.94–1.02)c
Thyroid cancer3060.95 (0.80–1.13)0.97 (0.81–1.16)1.01 (0.85–1.19)1.01 (0.86–1.20)0.95 (0.84–1.07)0.97 (0.86–1.09)
Colorectal cancer1861.06 (0.86–1.30)1.07 (0.86–1.31)0.87 (0.63–1.20)0.87 (0.63–1.20)1.05 (0.92–1.20)1.06 (0.92–1.21)
Non-Hodgkin lymphoma1851.10 (0.90–1.34)1.10 (0.90–1.34)1.09 (0.89–1.33)1.09 (0.89–1.33)1.05 (0.92–1.21)1.05 (0.91–1.20)
Endometrial cancer1000.80 (0.50–1.27)0.82 (0.52–1.30)d0.93 (0.60–1.43)0.97 (0.64–1.50)d0.86 (0.63–1.16)0.89 (0.66–1.19)d
Other cancers7150.97 (0.87–1.09)0.95 (0.85–1.07)0.93 (0.82–1.06)0.92 (0.81–1.05)1.01 (0.94–1.08)0.99 (0.92–1.06)
  • aAverage number of tanning bed use during high school/college and at ages 25 to 35.

  • bAdjusted for age, body mass index (BMI, <25, 25–29, 30–34, 35+ kg/m2), alcohol consumption (none, 1–4, 5–9, 10–14, 15+ g/wk), physical activity (<3, 3–8, 9–17, 18–26, 27+ met • h/wk), multivitamin use (yes, no), smoking status (never, past smoker, current smoker), oral contraceptive use (never, past use, current use), menopausal status and use of hormone replacement therapy (premenopause, postmenopause without hormone replacement therapy, postmenopause with hormone replacement therapy), outdoor sun exposure during high school/college and at ages 25 to 35, UV index of residence (at birth, age 15, and age 30), as well as dietary and supplemental vitamin D intake.

  • cIn addition adjusted for the history of benign breast disease (yes, no), family history of breast cancer (yes, no), parity and age at first birth (nulliparous, age at first birth <25 and parity 1–2, age at first birth 25–29 and parity 1–2, age at first birth 30+ and parity 1–2, age at first birth <25 and parity 3+, and age at first birth 25+ and parity 3+), age at menarche (<12, 12, 13, 14+), height (<1.60, 1.60–1.64, 1.65–1.70, 1.70+ m), and BMI at age 18 (<20, 20–22.4, 22.5–24, 25+ kg/m2).

  • dIn addition adjusted for parity and age at first birth (nulliparous, age at first birth <25 and parity 1–2, age at first birth 25–29 and parity 1–2, age at first birth 30+ and parity 1–2, age at first birth < 25 and parity 3+, and age at first birth 25+ and parity 3+), and age at menarche (<12, 12, 13, 14+).