The association of indoor tanning and melanoma in adults: Systematic review and meta-analysis

Background: Tanning beds are associated with increased risk of melanoma. Objective: We sought to update the evidence of the association of melanoma and indoor tanning focusing on frequency of use and exposure to newer tanning beds. Methods: We searched Scopus, MEDLINE, and Cumulative Index to Nursing and Allied Health Literature on August 14, 2013. We included all observational studies that included patients with melanoma who had indoor tanned. Odds ratios (OR) with 95% confidence intervals (CI) were extracted and combined using generic inverse variance methods assuming a random effects model. Results: In all, 31 studies were included with data available on 14,956 melanoma cases and 233,106 controls. Compared with never using, the OR for melanoma associated with ever using indoor tanning beds was 1.16 (95% CI 1.05-1.28). Similar findings were identified in recent studies with enrollment occurring in the year 2000 onward (OR 1.22, 95% CI 1.03-1.45) and in subjects attending more than 10 tanning sessions (OR 1.34, 95% CI 1.05-1.71). Limitations: The quality of evidence contributing to review results ranges from poor to mediocre. Conclusion: Using tanning beds is associated with a subsequent melanoma diagnosis. Exposure from more than 10 tanning sessions is most strongly associated and there was no statistically significant difference in this association before and after 2000, suggesting that newer tanning technology is not safer than older models.