Neighbourhood green space and the odds of having skin cancer: multilevel evidence of survey data from 267 072 Australians

Background If green spaces encourage people to spend more time outdoors in physical, recreational and social activities, this could have unintended but important consequences for health in countries where levels of ultraviolet (UV) radiation are non-trivial. We investigated whether people who lived in neighbourhoods containing lots of green space were likely to spend more time outdoors and, subsequently, were more likely to report a case of skin cancer. Methods Multilevel logit regression was used to fit associations between self-reported medically diagnosed skin cancer (melanoma and non-melanoma) and an objective measure of green space. These models were adjusted for measures of susceptibility (skin colour and tanning), socioeconomic variables, demographic and cultural characteristics (eg, ancestry and country of birth). Mediation analyses were conducted using self-reported measures of time spent outdoors and participation in moderate-to-vigorous physical activity (MVPA). Results Descriptive analyses reported a positive association between green space and skin cancer (p<0.001). Time outdoors and in MVPA was also higher among people living in greener areas. The association between green space and skin cancer was robust after adjustment. In comparison to people with 0-20% green space, for example, the adjusted odds of having skin cancer were 9% higher among those with >80% green space. Only 1.6% and less than 1% of the association was mediated by MVPA and time spent outdoors. Conclusions Neighbourhood green space is associated with higher odds of having skin cancer in Australia. The relationship between green space and health, in its broadest terms, is likely to vary by geographical context.