Text-Attributed Knowledge Graph Enrichment with Large Language Models for Medical Concept Representation

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Kerdabadi, Mohsen Nayebi, Moghaddam, Arya Hadizadeh, Chen, Chen, Wang, Dongjie, Yao, Zijun
Natura: Preprint
Pubblicazione: 2026
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866915973060100096
author Kerdabadi, Mohsen Nayebi
Moghaddam, Arya Hadizadeh
Chen, Chen
Wang, Dongjie
Yao, Zijun
author_facet Kerdabadi, Mohsen Nayebi
Moghaddam, Arya Hadizadeh
Chen, Chen
Wang, Dongjie
Yao, Zijun
contents In electronic health record (EHR) mining, learning high-quality representations of medical concepts (e.g., standardized diagnosis, medication, and procedure codes) is fundamental for downstream clinical prediction. However, ro bust concept representation learning is hindered by two key challenges: (i) clinically important cross-type dependencies (e.g., diagnosis medication and medication-procedure relations) are often missing or incomplete in existing ontology resources, limiting the ability to model complex EHR patterns; and (ii) rich clinical semantics are often missing from structured resources, and even when available as text, are difficult to integrate with KG structure for representation learning. To address these challenges, we present MedCo, an LLM empowered graph learning framework for medical concept representation. MedCo first builds a global knowledge graph (KG) over medical codes by combining statistically reliable associations mined from EHRs with type-constrained LLM prompting to infer semantic relations. It then utilizes LLMs to enrich the KG into a text-attributed graph by generating node descriptions and edge rationales, providing semantic signals for both concepts and their relationships. Finally, MedCo jointly trains a LoRA-tuned LLaMA text encoder with a heterogeneous GNN, fusing text semantics and graph structure into unified concept embeddings. Extensive experiments on MIMIC-III and MIMIC-IV show that MedCo consistently improves prediction performance and serves as an effective plug-in concept encoder for standard EHR pipelines.
format Preprint
id arxiv_https___arxiv_org_abs_2604_13331
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Text-Attributed Knowledge Graph Enrichment with Large Language Models for Medical Concept Representation
Kerdabadi, Mohsen Nayebi
Moghaddam, Arya Hadizadeh
Chen, Chen
Wang, Dongjie
Yao, Zijun
Machine Learning
In electronic health record (EHR) mining, learning high-quality representations of medical concepts (e.g., standardized diagnosis, medication, and procedure codes) is fundamental for downstream clinical prediction. However, ro bust concept representation learning is hindered by two key challenges: (i) clinically important cross-type dependencies (e.g., diagnosis medication and medication-procedure relations) are often missing or incomplete in existing ontology resources, limiting the ability to model complex EHR patterns; and (ii) rich clinical semantics are often missing from structured resources, and even when available as text, are difficult to integrate with KG structure for representation learning. To address these challenges, we present MedCo, an LLM empowered graph learning framework for medical concept representation. MedCo first builds a global knowledge graph (KG) over medical codes by combining statistically reliable associations mined from EHRs with type-constrained LLM prompting to infer semantic relations. It then utilizes LLMs to enrich the KG into a text-attributed graph by generating node descriptions and edge rationales, providing semantic signals for both concepts and their relationships. Finally, MedCo jointly trains a LoRA-tuned LLaMA text encoder with a heterogeneous GNN, fusing text semantics and graph structure into unified concept embeddings. Extensive experiments on MIMIC-III and MIMIC-IV show that MedCo consistently improves prediction performance and serves as an effective plug-in concept encoder for standard EHR pipelines.
title Text-Attributed Knowledge Graph Enrichment with Large Language Models for Medical Concept Representation
topic Machine Learning
url https://arxiv.org/abs/2604.13331