Does fast-food outlet density differ by area-level disadvantage in metropolitan Perth, Western Australia?

Abstract

Socio-economic spatial patterning of fast-food outlets can result in disparities in the availability and access of food across geographic areas, contributing to health inequalities. This study investigated whether area-level socio-economic disparities exist in fast-food availability across the Perth metropolitan region of Western Australia. Fast-food outlet locations were sourced from Perth Local Governments in 2018/2019. All Perth suburbs (n=328) were allocated a decile ranking based on the Australian Bureau of Statistics Socio-Economic Index for Areas with decile 1 indicating relatively greater disadvantage and decile 10 indicating a relative lack of disadvantage. Zero-inflated negative binomial regression models, adjusted for suburb area and population density, were used to investigate the association between area-level disadvantage decile and availability of fast-food outlets. A socio-economic gradient was identified; for every unit increase in disadvantage decile (ie a reduction in relative disadvantage), the count of fast-food outlets decreased by 6% (P<.01), and the count of the "top ranking" fast-food chains (ie McDonalds, KFC, Hungry Jacks and Red Rooster) decreased by 10% (P<.001). Consistent with evidence internationally and from within Australia, socio-economic spatial patterning of fast-food outlet availability was shown to exist in Perth, with greater fast-food availability in areas with more relative socio-economic disadvantage. SO WHAT?: To address health inequities associated with fast-food consumption, policy and practice changes are needed that manage fast-food outlet proliferation in areas of greater socio-economic disadvantage.