Language Models for Longitudinal Clinical Prediction
Tananun Songdechakraiwut, Michael Lutz
TL;DR
The paper tackles forecasting longitudinal neuropsychological trajectories in Alzheimer's disease from sparsely observed data. It proposes a data-efficient framework that keeps a large language model frozen while introducing prompt-based conditioning, temporal patch embeddings, and cross-modal semantic mapping to produce multi-target forecasts over horizons from $12$ to $48$ months, trained with a lightweight decoder. Key contributions include demonstrating strong predictive accuracy across four clinically relevant targets on the ADNI dataset, robustness under limited supervision (down to $1\%$ of training data), and an ablation-enabled understanding of how RevIN normalization, prompts, and semantic prototypes drive performance. The approach offers a scalable, deployment-friendly pathway for early-stage Alzheimer's monitoring and personalized planning with minimal annotated data, potentially informing clinical decisions and trial design.
Abstract
We explore a lightweight framework that adapts frozen large language models to analyze longitudinal clinical data. The approach integrates patient history and context within the language model space to generate accurate forecasts without model fine-tuning. Applied to neuropsychological assessments, it achieves accurate and reliable performance even with minimal training data, showing promise for early-stage Alzheimer's monitoring.
