Prevalence and characteristics of choroidal nevi: the Australian National Eye Health Survey

ImportanceChoroidal nevi are a common incidental finding on fundus examination. The National Eye Health Survey (NEHS, 2015-2016) provides an up-to-date estimate of the prevalence of choroidal nevi in non-Indigenous and Indigenous Australian adults. BackgroundTo describe the prevalence and characteristics of choroidal nevi among non-Indigenous and Indigenous Australian adults. DesignPopulation-based cross-sectional study. ParticipantsThis study included 3098 non-Indigenous Australians (aged 50-98years) and 1738 Indigenous Australians (aged 40-92years) living in 30 randomly selected sites, stratified by remoteness. MethodsChoroidal nevi were graded from retinal photographs using standard protocols. Main Outcome MeasuresPrevalence of choroidal nevi. ResultsIn the non-Indigenous population aged 50years and over, the weighted prevalence of choroidal nevi was 2.1% (95% CI: 1.4, 3.3). Among Indigenous Australians aged 40years and over, the weighted prevalence of choroidal nevi was 0.68% (95% CI: 0.4, 1.3). The average maximum diameter, surface area and distance from the disc of the choroidal nevi was 1730m, 2766800 m(2) and 3400m, respectively. After multivariate adjustments, Indigenous participants (OR= 0.28, P = 0.01) and those of older age (OR= 0.79 per 10 years, P = 0.02) were less likely to have choroidal nevi. Choroidal nevus was not the primary cause of vision loss in any participant. Conclusions and RelevanceChoroidal nevi were relatively infrequent among NEHS participants, however non-Indigenous Australians had a significantly higher prevalence than Indigenous Australians. Choroidal nevi did not affect visual acuity and the majority were small.