Forno Gonzalo, Vidal Julie P, Rush Phoebe, Tan Rachel, Aggleton John P, Barbeau Emmanuel J, Hornberger Michael
Geroscience Center for Brain Health and Metabolism (GERO), Santiago, Chile; Neuropsychology and Clinical Neuroscience Laboratory (LANNEC), Physiopathology Department - ICBM, Neuroscience and East Neuroscience Departments, Faculty of Medicine, University of Chile, Avenida Salvador 486, Providencia, Santiago, Chile.
CNRS, CerCo (Brain and Cognition Research Center, UMR5549), Toulouse University, Toulouse, France; INSERM, ToNiC (Toulouse NeuroImaging Center), Paul Sabatier University, Toulouse, France.
Brain Res Bull. 2025 Oct 15;231:111559. doi: 10.1016/j.brainresbull.2025.111559. Epub 2025 Sep 23.
The interthalamic adhesion (IA) is an anatomical bridge connecting the left and right thalamus. While prior studies have explored its prevalence and function in healthy populations, stroke, hydrocephalus, and schizophrenia, none have examined the IA in the context of Alzheimer's disease (AD). This study aims to analyse the prevalence of the IA in the prodromal to clinical AD continuum and evaluate the association with AD cerebrospinal fluid (CSF) biomarkers and thalamic, hippocampal, and ventricular volumes.
IA prevalence was assessed in 542 MRIs from the Alzheimer's Disease Neuroimaging Initiative (ADNI), including healthy controls (HC), early mild cognitive impairment (EMCI), late MCI (LMCI), and AD patients. Inter-rater reliability was assessed with Cohen's Kappa, and a chi-squared test (χ2) examined rater differences. Binary and multinomial logistic regressions evaluated the effect of CSF biomarkers, volumes, and clinical data on IA prevalence and type.
There were no significant differences in IA prevalence or variants across the four groups. The single IA was the most common type, while bilobar and double variants were less frequent. Post-hoc analysis, however, showed that AD CSF biomarker measures showed positive associations with the broad IA subtype in HC and EMCI.
The study found no overall differences in IA prevalence or its variants related to prodromal or clinical AD. Still, elevated Aβ42, p-Tau levels, and larger thalamic volume were linked to a higher likelihood of a broad IA. These findings suggest that the IA may be involved in prodromal AD pathophysiological processes.
丘脑间粘合（IA）是连接左右丘脑的解剖学桥梁。虽然先前的研究已经探讨了其在健康人群、中风、脑积水和精神分裂症中的患病率及功能，但尚无研究在阿尔茨海默病（AD）背景下对IA进行研究。本研究旨在分析前驱期至临床期AD连续体中IA的患病率，并评估其与AD脑脊液（CSF）生物标志物以及丘脑、海马和脑室体积的相关性。
在来自阿尔茨海默病神经影像倡议（ADNI）的542例MRI中评估IA患病率，包括健康对照（HC）、早期轻度认知障碍（EMCI）、晚期MCI（LMCI）和AD患者。使用科恩kappa系数评估评分者间信度，并通过卡方检验（χ2）检查评分者差异。二元和多项逻辑回归评估CSF生物标志物、体积和临床数据对IA患病率和类型的影响。
四组之间的IA患病率或变体无显著差异。单一IA是最常见的类型，而双叶和双重变体较少见。然而，事后分析表明，AD CSF生物标志物测量值在HC和EMCI中与广泛的IA亚型呈正相关。
该研究发现IA患病率或其变体与前驱期或临床期AD无关。尽管如此，Aβ42、p-Tau水平升高以及丘脑体积较大与广泛IA的可能性较高有关。这些发现表明IA可能参与前驱期AD的病理生理过程。
