Classification and prediction of Alzheimer's disease stages and conversion from mild cognitive impairment based on multimodal data fusion.

Objective: This study aimed to develop multimodal prediction models based on real-world clinical data for classifying different stages of Alzheimer's disease (AD) and for predicting the conversion from mild cognitive impairment (MCI) to AD. Methods: A single-center retrospective real-world cohort study was conducted. A total of 658 individuals aged ≥50 years were included and classified into cognitively normal (CN), MCI, and AD groups. Demographic characteristics, neurocognitive assessment results, conventional magnetic resonance imaging (MRI) features, and blood-based biomarkers were collected. Logistic regression was used to construct pairwise classification models for disease stages and prediction models for MCI-to-AD conversion. Model performance was evaluated through stepwise integration of multimodal features. Discrimination ability was assessed using the area under the receiver operating characteristic curve (AUC), together with calibration curves and decision curve analysis. In a sub-cohort with thin-slice MRI data, the additional value of hippocampal volume was further examined. Results: Significant differences were observed among disease stages in cognitive function, imaging markers, and blood biomarkers (all Conclusion: Multimodal prediction models based on real-world clinical data improved the accuracy of AD stage classification and the prediction of MCI-to-AD conversion risk. These models demonstrated good clinical feasibility. High-resolution structural imaging markers further enhanced predictive performance in selected populations.