Late-life depression (LLD) is characterized by medial temporal lobe (MTL) abnormalities. Although gray matter (GM) and white matter (WM) differences in LLD have been reported, few studies have investigated them concurrently. Moreover, the impact of aetiological factors, such as neurodegenerative and cerebrovascular burden, on tissue differences remains elusive.

This prospective cross-sectional study involved 72 participants, including 33 patients with LLD (mean age 72.2 years, 23 female) and 39 healthy controls (HCs) (mean age 70.6 years, 24 female), who underwent clinical and positron emission tomography (PET)-magnetic resonance imaging (MRI) assessments. High-resolution 3D T1-weighted and T2-weighted FLAIR images were used to assess MTL GM volumes and white matter hyperintensities (WMHs), a proxy for cerebrovascular burden. Diffusion kurtosis imaging metrics derived from multishell diffusion MRI data were analyzed to assess WM microstructure in the following MTL bundles reconstructed using constrained spherical deconvolution tractography: uncinate fasciculus, fornix, and cingulum. Standardized uptake value ratio of 18F-MK-6240 in the MTL was used to assess Alzheimer’s disease (AD) type tau accumulation as a proxy for neurodegenerative burden.

Compared to HCs, patients with LLD showed significantly lower bilateral MTL volumes and WM microstructural differences primarily in the uncinate fasciculi bilaterally and right fornix. In patients with LLD, higher vascular burden, but not tau, was associated with lower MTL volume and more pronounced WM differences.

LLD was associated with both GM and WM differences in the MTL. Cerebrovascular disease, rather than AD type tau-mediated neurodegenerative processes, may contribute to brain tissue differences in LLD.

Very-late-onset schizophrenia-like psychosis (VLOSLP) is associated with significant burden. Its clinical importance is increasing as the global population of older adults rises, yet owing to limited research in this population, the neurobiological underpinnings of VLOSP remain insufficiently clarified. Here we address this knowledge gap using novel morphometry techniques to investigate grey matter volume (GMV) differences between VLOSLP and healthy older adults, and their correlations with neuropsychological scores.

In this cross-sectional study, we investigated whole-brain GMV differences between 35 individuals with VLOSLP (mean age 76.7, 26 female) and 36 healthy controls (mean age 75.7, 27 female) using whole-brain voxel-based morphometry (VBM) and supplementary source-based morphometry (SBM) on high resolution 3D T1-weighted MRI images. Additionally, we investigated relationships between GMV differences and cognitive function assessed with an extensive neuropsychological battery.

VBM showed lower GMV in the thalamus, left inferior frontal gyrus and left insula in patients with VLOSLP compared to healthy controls. SBM revealed lower thalamo-temporal GMV in patients with VLOSLP. Processing speed, selective attention, mental flexibility, working memory, verbal memory, semantic fluency and confrontation naming were impaired in patients with VLOSLP. Correlations between thalamic volumes and memory function were significant within the group of individuals with VLOSLP, whereas no significant associations remained in the healthy controls.

Lower GMV in the thalamus and fronto-temporal regions may be part of the underlying neurobiology of VLOSLP, with lower thalamic GMV contributing to memory impairment in the disorder.

To examine whether previously established associations between experiences of meaning in life on the one hand and life satisfaction and depressive symptoms on the other hand are transferable to a population of older residential care residents with Alzheimer’s disease (AD).

Cross-sectional study using questionnaires administered in a structured interview format.

Nine residential care settings in Flanders, Belgium.

Convenience sample of 138 older adults (+65) living in residential care with a diagnosis of AD.

Meaning in life was measured using the Presence of Meaning (PoM) subscale of the Meaning in Life Questionnaire-Short Form, life satisfaction was measured using the Satisfaction With Life Scale (SWLS), depressive symptoms were measured using a five-item short form of the Geriatric Depression Scale (GDS), and general cognitive status was measured using the Mini-Mental State Examination (MMSE).

Controlling for demographic variables (age, sex, and marital status) and cognitive status, meaning in life scores were positively predictive of life satisfaction scores and negatively predictive of depressive symptoms. Post-hoc analyses suggested a possible interaction between meaning in life and cognitive status in predicting both outcomes of psychological functioning (GDS and SWLS).

The presence of meaning in life is related to important well-being outcomes for older adults with AD living in residential care. More awareness for the importance of existential themes and interventions fostering meaning might be warranted for this population.

Despite the benefits of being active for people with mild cognitive impairment (MCI) on cognition and the acknowledgement that MCI is a critical period for intervening to prevent dementia, little is known about the actual sedentary levels in people with MCI. This study investigates correlates of sedentary behavior (SB) in people with MCI.

This was a cross-sectional study.

Data from the World Health Organization’s Study on Global Ageing and Adult Health were analyzed.

Individuals aged ≥50 years with MCI were included.

SB was assessed by the Global Physical Activity Questionnaire. Associations between SB levels and the correlates were examined using multivariable linear and logistic regressions.

4,082 individuals aged ≥50 years with MCI (64.4 ± 17.0 years; 55.1% female) were included. The prevalence of high SB (i.e., ≥8 hours/day) was 14.0% (95%CI = 12.2%–16.0%), while the time spent sedentary was 262 ± 290 minutes/day. Correlates significantly associated with being sedentary ≥8 hours/day and time spent sedentary per day were, older age, being unemployed, depression, sleep problems, obesity (vs. normal weight), diabetes, stroke, poor self-rated health, and lower levels of social cohesion.

Future research exploring interventions to reduce SB in people with MCI should target the identified sociodemographic and mental and physical health correlates, while the promotion of social cohesion may have the potential to increase the efficacy of future public health initiatives.