Late-life cynical hostility is associated with white matter alterations and the risk of Alzheimer's disease

Background Cynical hostility (CH), a specific dimension of hostility that consists of a mistrust of others, has been suggested as a high-risk trait for dementia. However, the influence of CH on the incidence of Alzheimer's disease (AD) remains poorly understood. This study investigated whether late-life CH is associated with AD risk and structural neuroimaging markers of AD. Methods In community-dwelling older adults from the French ESPRIT cohort (n = 1388), incident dementia rate according to CH level was monitored during an 8-year follow-up and analyzed using Cox proportional hazards regression models. Brain magnetic resonance imaging volumes were measured at baseline (n = 508). Using automated segmentation procedures (Freesurfer 6.0), the authors assessed brain grey and white volumes on all magnetic resonance imaging scans. They also measured white matter hyperintensities volumes using semi-automated procedures. Mean volumes according to the level of CH were compared using ANOVA. Results Eighty-four participants developed dementia (32 with AD). After controlling for potential confounders, high CH was predictive of AD (HR 2.74; 95% CI 1.10-6.85; p = 0.030) and all dementia types are taken together (HR 2.30; 95% CI 1.10-4.80; p = 0.027). High CH was associated with white matter alterations, particularly smaller anterior corpus callosum volume (p < 0.01) after False Discovery Rate correction, but not with grey matter volumes. Conclusions High CH in late life is associated with cerebral white matter alterations, designated as early markers of dementia, and higher AD risk. Identifying lifestyle and biological determinants related to CH could provide clues on AD physiopathology and avenues for prevention strategies.