Warmer Temperatures Are More Predictive Than Solar Radiation for the Number of Skin Cancer Removal Procedures

Solar radiation is the primary risk factor for skin cancer, with personal exposure influenced by environmental and behavioral factors. At higher temperatures, behavioral changes increase solar radiation exposure.

Examine the relationships between solar radiation, ambient temperature, age, and skin cancer.

For the contiguous United States, we obtained the state mean global horizontal irradiance (GHI), daily maximum temperature, and number of skin cancer removals in the Medicare population. For skin cancer removals, we defined more sun-exposed skin as the head, neck, hands, and feet, and less sun-exposed skin as the trunk, arms, and legs.

By comparing the temperature thresholds 17°C, 20°C, 24°C, 27°C, 31°C, and 34°C, we found that the annual number of days above 24°C was the strongest temperature-related predictor of skin cancer removals. Multivariable linear regression showed that the number of days above 24°C predicted more skin cancer removals for all body locations and less sun-exposed skin (p = 0.008 and p = 0.003, respectively), while GHI did not (p = 0.1 and p = 0.8, respectively). GHI only predicted more skin cancer removals for more sun-exposed skin (p = 0.02).

More days above 24°C was a better predictor of skin cancer removals than GHI for all skin locations and less sun-exposed skin, suggesting that the behavioral changes occurring at warmer temperatures are more predictive of skin cancer removals than solar irradiance. Due to rising global temperatures, skin cancer incidence may further increase. Temperature-related behavioral changes represent a potential target for skin cancer prevention efforts.