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Uiwon Hwang , Euideuk Hwang , Minsoo Kang , Sungroh Yoon

Prediction of Mortality and Intervention in COVID-19 Patients �Using Generative Adversarial Networks

Seoul National University

Kyungpook National University

 

speaker

 

The 1st Workshop on Healthcare AI and COVID-19, ICML 2022

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Coronavirus disease 2019

    • Numerous countries have faced shortage of medical resources, including beds and medical staff

🡪 COVID-19 pandemic poses an unprecedented threat to health and public health around the world

COVID-19

COVID-19

Since

December 2019

# of confirmed cases�> 500 million

Death toll

> 6 million

(up to May 16, 2022)

40%

40%

Silent

20%

10%

Clinical manifestation

Pneumonia

Hypoxemic pneumonia

: requires oxygen treatment

40%

Benign upper respiratory ds.

Wynants, Laure, et al. "Prediction models for diagnosis and prognosis of covid-19: systematic review and critical appraisal." bmj 369 (2020).

Zhang, Qian, et al. "Human genetic and immunological determinants of critical COVID-19 pneumonia." Nature 603.7902 (2022): 587-598.

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Coronavirus disease 2019

  • Mortality prediction in COVID-19 patients is necessary
    • To efficiently allocate limited medical resources and provide the best treatment to patients

  • Timely clinical interventions (e.g. intubation, supplemental oxygen) is important
    • To decrease the death rate of COVID-19 patients

🡪 ML models that predict the mortality and intervention can be of great help to � the public health crises and patients’ lives

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Dataset

  • Limited data problems in electronic health records (EHRs)
    • Missing data problem: some attributes can be missing
    • Class imbalance problem: outcomes can be imbalanced
    • Missing label problem: outcomes can be missing

Attributes in EHR

Class

# of samples

Unlabeled data

(Missing label)

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9

Missing values

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Dataset

  • Covid-chestxray-dataset
    • Chest X-ray images + Metadata
    • 846 records: 468 records obtained from COVID-19 patient + 378 records obtained from other pneumonias

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Cohen, Joseph Paul, Paul Morrison, and Lan Dao. "COVID-19 image data collection." arXiv preprint arXiv:2003.11597 (2020).

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Method

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Real?�Fake?

real data distribution

generated data distribution

loss metrics

Arjovsky, Martin, Soumith Chintala, and Léon Bottou. "Wasserstein generative adversarial networks." International conference on machine learning. PMLR, 2017.

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Method

  • HexaGAN

  • Hint mechanism

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Hint generator�(𝑤.𝑝. hint rate)

 

 

 

 

 

 

 

 

 

 

 

 

 

Hwang, Uiwon, et al. "Hexagan: Generative adversarial nets for real world classification." International Conference on Machine Learning. PMLR, 2019.

Yoon, Jinsung, et al. "Gain: Missing data imputation using generative adversarial nets." International conference on machine learning. PMLR, 2018.

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Overview

Chest X-ray

 

 

 

 

Metadata

(w/ missing data)

 

 

 

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Missingness�vector

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0.5

0.5

 

 

 

 

 

HexaGAN

survival

intubation

oxygen

Prediction

Proper�treatment

Hint mechanism

Hint generator�(𝑤.𝑝. hint rate)

Dataset

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Results

  • Mortality prediction (survival)

Hint rate

Hint rate

F1-score

Specificity

x2

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Results

  • Intervention prediction
    • Intubation prediction

    • Supplemental O2 prediction

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Discussion

  • ML perspective
    • Cascade combination of existing ML methods
      • Requires building a pre-processing pipeline that depends on problems present in the training data
      • Ignores the connections between the problems

    • HexaGAN
      • No need to build a specific preprocessing pipeline
      • Deals with limited data problems simultaneously through interaction between its components

Real world data

HexaGAN

Method for �missing data problem

Method for �class imbalance problem

Method for �missing label problem

Classifier

EHRs

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Discussion

  • Medical perspective
    • The model presented in this study can predict survival, the use of supplemental oxygen, and intubation which are closely related to the severity of COVID-19
    • The early use of medicines according to the prediction of the model could be further investigated

    • GAN methods trained on datasets obtained from longitudinal studies can predict whether an intervention should be recommended at a particular moment
    • This will be an important avenue for future work to provide more timely treatment to COVID-19 patients in the presence of the limited data problems

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Thank you!

  • TL;DR
    • We construct a deep generative model to provide accurate prediction of mortality and interventions for COVID-19 patients from the dataset with limited data problems

  • Summary
    • Use HexaGAN which addresses limited data problems simultaneously and apply a hint mechanism to enhance the prediction performance
      • Significantly outperform combinations of existing methods

    • Anticipate that our approach could help
      • Provide appropriate treatments on time
      • Allocate limited medical resources efficiently
      • Reduce the mortality rate of COVID-19 patients