Two-Year Longitudinal Outcomes of Subjective Cognitive Decline in Hispanics Compared to Non-hispanic Whites.

Background: Subjective cognitive decline (SCD), considered a preclinical dementia stage, is less understood in Hispanics, a high-risk group for dementia. We investigated SCD to mild cognitive impairment (MCI) progression risk, as well as baseline and longitudinal features of depressive symptoms, SCD complaints, and objective cognitive performance among Hispanics compared to non-Hispanic Whites (NHW).

Methods: Hispanic (n = 23) and NHW (n = 165) SCD participants were evaluated at baseline and 2-year follow-up. Evaluations assessed function, depressive symptoms, SCD, and objective cognitive performance.

Results: Hispanics were at increased risk of progression to MCI (OR: 6.10, 95% CI 1.09-34.20, P = .040). Hispanic participants endorsed more depressive symptoms at baseline (P = .048) that worsened more longitudinally (OR: 3.16, 95% CI 1.18-8.51, P = .023). Hispanic participants had increased SCD complaints on the Brief Cognitive Rating Scale (BCRS) (β = .40 SE: .17, P = .023), and in specific BCRS domains: concentration (β = .13, SE: .07, P = .047), past memory (β = .13, SE: .06, P = .039) and functional abilities (β = .10, SE: .05, P = .037). In objective cognitive performance, Hispanic ethnicity associated with decline in MMSE (β = -.27, SE: .13, P = .039), MoCA (β = -.80 SE: .34, P = .032), Trails A (β = 2.75, SE: .89, P = .002), Trails B (β = 9.18, SE: 2.71, P = .001) and Guild Paragraph Recall Delayed (β = -.80 SE: .28, P = .005). Conclusions: Hispanic ethnicity associated with a significantly increased risk of 2-year progression of SCD to MCI compared to NHW. This increased risk associated with increased depressive symptoms, distinctive SCD features, and elevated amnestic and non-amnestic objective cognitive decline. This supports further research to refine the assessment of preclinical dementia in this high-risk group.