title: Use of tanning beds and incidence of skin cancer.
abstract: OBJECTIVE
  We sought to evaluate the risk effect of tanning bed use on skin cancers among teenage and young adults. We also expected to determine whether a dose-response relationship was evident.
  
  
  METHODS
  We observed 73,494 female nurses for 20 years (from 1989 to 2009) in a large and well-characterized cohort in the United States and investigated whether frequency of tanning bed use during high school/college and at ages 25 to 35 years were associated with a risk of basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma. We used Cox proportional hazards models and carefully adjusted for host risk factors, ultraviolet index of residence, and sun exposure behaviors at a young age.
  
  
  RESULTS
  During follow-up, 5,506 nurses were diagnosed with BCC, 403 with SCC, and 349 with melanoma. The multivariable-adjusted hazard ratio (HR) of skin cancer for an incremental increase in use of tanning beds of four times per year during both periods was 1.15 (95% CI, 1.11 to 1.19; P < .001) for BCC, 1.15 (95% CI, 1.01 to 1.31; P = .03) for SCC, and 1.11 (95% CI, 0.97 to 1.27; P = .13) for melanoma. Compared with tanning bed use at ages 25 to 35 years, we found a significantly higher risk of BCC for use during high school/college (multivariable-adjusted HR for use more than six times per year compared with no use was 1.73 during high school/college v 1.28 at ages 25 to 35 years; P for heterogeneity < .001).
  
  
  CONCLUSIONS
  Our data provide evidence for a dose-response relationship between tanning bed use and the risk of skin cancers, especially BCC, and the association is stronger for patients with a younger age at exposure.
authors.affiliation: Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Mingfeng
authors.initials: M
authors.lastname: Zhang
authors.forename: Abrar A
authors.initials: AA
authors.lastname: Qureshi
authors.forename: Alan C
authors.initials: AC
authors.lastname: Geller
authors.forename: Lindsay
authors.initials: L
authors.lastname: Frazier
authors.forename: David J
authors.initials: DJ
authors.lastname: Hunter
authors.forename: Jiali
authors.initials: J
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001505:Beauty Culture / Q000295:instrumentation*; D002280:Basal Cell Carcinoma / Q000453:epidemiology* / Q000209:etiology; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000209:etiology; D015331:Cohort Studies; D016001:Confidence Intervals; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D015994:Incidence; D008545:Melanoma / Q000453:epidemiology* / Q000209:etiology; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012878:Skin Neoplasms / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology; D055107:Suntan; D014466:Ultraviolet Rays / Q000009:adverse effects*; D055815:Young Adult