Combination of white matter hyperintensities and Aβ burden is related to cognitive composites domain scores in subjective cognitive decline: the FACEHBI cohort

BACKGROUND: To explore whether the combination of white matter hyperintensities (WMHs) and amyloid-beta (Aβ) deposition is associated with worse cognitive performance on cognitive composites (CCs) domain scores in individuals with subjective cognitive decline (SCD). METHODS: Two hundred participants from the FACEHBI cohort underwent structural magnetic resonance imaging (MRI), (18)F-florbetaben positron emission tomography (FBB-PET), and neuropsychological assessment. WMHs were addressed through the Fazekas scale, the Age-Related White Matter Changes (ARWMC) scale, and the FreeSurfer pipeline. Eight CCs domain scores were created using the principal component analysis (PCA). Age, sex, education, and apolipoprotein E (APOE) were used as adjusting variables. RESULTS: Adjusted multiple linear regression models showed that FreeSurfer (B − .245; 95% CI − .1.676, − .393, p = .016) and β burden (SUVR) (B − .180; 95% CI − 2.140, − .292; p = .070) were associated with face–name associative memory CCs domain score, although the latest one was not statistically significant after correction for multiple testing (p = .070). There was non-significant interaction of these two factors on this same CCs domain score (p = .54). However, its cumulative effects on face–name associative performance indicated that those individuals with either higher WMH load or higher Aβ burden showed the worst performance on the face–name associative memory CCs domain score. CONCLUSIONS: Our results suggest that increased WMH load and increased Aβ are independently associated with poorer episodic memory performance in SCD individuals, indicating a cumulative effect of the combination of these two pathological conditions in promoting lower cognitive performance, an aspect that could help in terms of treatment and prevention.