Brain atrophy trajectories predict differential functional performance in Alzheimer's disease: Moderations with apolipoprotein E and sex

Associations of multiple visual rating scales based on structural magnetic resonance imaging with disease severity and cerebrospinal fluid biomarkers in patients with Alzheimer’s disease

The relationships between multiple visual rating scales based on structural magnetic resonance imaging (sMRI) with disease severity and cerebrospinal fluid (CSF) biomarkers in patients with Alzheimer’s disease (AD) were ambiguous. In this study, a total of 438 patients with clinically diagnosed AD were recruited. All participants underwent brain sMRI scan, and medial temporal lobe atrophy (MTA), posterior atrophy (PA), global cerebral atrophy-frontal sub-scale (GCA-F), and Fazekas rating scores were visually evaluated. Meanwhile, disease severity was assessed by neuropsychological tests such as the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Clinical Dementia Rating (CDR). Among them, 95 patients were tested for CSF core biomarkers, including Aβ_1–42, Aβ_1–40, Aβ_1–42/Aβ_1–40, p-tau, and t-tau. As a result, the GCA-F and Fazekas scales showed positively significant correlations with onset age (r = 0.181, p < 0.001; r = 0.411, p < 0.001, respectively). Patients with late-onset AD (LOAD) showed higher GCA-F and Fazekas scores (p < 0.001, p < 0.001). With regard to the disease duration, the MTA and GCA-F were positively correlated (r = 0.137, p < 0.05; r = 0.106, p < 0.05, respectively). In terms of disease severity, a positively significant association emerged between disease severity and the MTA, PA GCA-F, and Fazekas scores (p < 0.001, p < 0.001, p < 0.001, p < 0.05, respectively). Moreover, after adjusting for age, gender, and APOE alleles, the MTA scale contributed to moderate to severe AD in statistical significance independently by multivariate logistic regression analysis (p < 0.05). The model combining visual rating scales, age, gender, and APOE alleles showed the best performance for the prediction of moderate to severe AD significantly (AUC = 0.712, sensitivity = 51.5%, specificity = 84.6%). In addition, we observed that the MTA and Fazekas scores were associated with a lower concentration of Aβ_1–42 (p < 0.031, p < 0.022, respectively). In summary, we systematically analyzed the benefits of multiple visual rating scales in predicting the clinical status of AD. The visual rating scales combined with age, gender, and APOE alleles showed best performance in predicting the severity of AD. MRI biomarkers in combination with CSF biomarkers can be used in clinical practice.

Association of Arterial Stiffness with Functional Disability and Mobility Limitation: The Rugao Longitudinal Ageing Study

OBJECTIVES

Arterial stiffness is a common issue that may represent an indicator of vascular ageing. We aimed to investigate the association of arterial stiffness with the risk of functional disability and mobility limitation in older adults.

DESIGN

Prospective cohort study.

SETTING AND PARTICIPANTS

A total of 1699 older adults from the Rugao Longitudinal Ageing Study were included and analysed.

MEASUREMENTS

Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV). Functional disability and mobility limitation were evaluated by the activities of daily living and the Timed Up and Go test, respectively. The associations of baPWV and risk of functional disability and mobility limitation were analysed using logistic regression models. Restricted cubic spline regressions were applied to estimate the possible nonlinear relationships between them.

RESULTS

During the 3.5-year follow-up, 97 (10.00%) and 285 (31.11%) individuals were defined as new-onset functional disability and mobility limitation, respectively. After adjusting for confounding factors, elevated baPWV was significantly associated with a higher risk of incident functional disability (odds ratio [OR] 1.18, 95% confidence interval [CI] 1.06-1.31) and mobility limitation (OR 1.08, 95% CI 1.01-1.16). Additionally, consistent results were obtained from the stratified analyses of the different subgroups. Multivariable restricted cubic spline regression analysis further demonstrated that a near-linear association occurred between baPWV and the risk of incident functional disability and mobility limitation (P-overall < 0.01, P-nonlinear >0.05).

CONCLUSION

Arterial stiffness, as assessed by baPWV, was associated with the risk of functional disability and mobility limitation in this community-based cohort, and these associations were nearly linear.