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Australian & New Zealand Journal of Psychiatry, 49(1) Converging clinical evidence suggests that in otherwise healthy older adults an increase in depressive symptoms can be an early or preclinical indicator of dementia (Byers and Yaffe, 2011). The most common type of dementia, Alzheimer’s disease (AD), accounts for 70 % of cases worldwide (World Health Organisation, 2012). Evidence for a relationship between depression and AD comes from observations that a clinical diagnosis of depression in both early and late life increases the risk for AD diagnosis in healthy older adults (Da Silva et al., 2013; Vilalta-Franch et al., 2013) and in individuals who meet criteria for mild cognitive impairment (MCI) (Richard et al., 2013). Authoritative reviews also conclude that an increased num-ber, longer duration and higher frequency of depressive episodes across the lifespan further increase the risk of developing AD (Byers and Yaffe, 2011; Piccinni et al., 2013). However, these reviews also emphasise that associa-tions between depressive symptoms and clinically diag-nosed AD are not evident in all studies (Luppa et al., 2013; Neubauer et al., 2013; Wilson et al., 2010). Thus, factors such as methodology, context, or the presence of subgroups of people with depression and additional risk factors for AD (e.g. apolipoprotein ε4 [APOE ε4] carriage) (Corder et al., 1993) may influence the extent to which depressive symptoms can predict clinical AD (Byers and Yaffe, 2011). Several factors that complicate determination of the extent to which depressive symptoms are related to early Amyloid-beta and depression in healthy older adults: A systematic revie