Related Experiment Video
Updated: Aug 14, 2025
Monitoring PD-1-Blocking Antibodies Bound to T Cells Derived from a Drop of Peripheral Blood
Published on: February 5, 2020
Burden of Cardiovascular Disease in Immune Checkpoint Inhibitor-Treated Patients: Reconciling Adjudicated and Coded
Lavanya Kondapalli1, Judith Hsia1,2, Ronni Miller3
1Division of Cardiology, University of Colorado School of Medicine, Aurora, Colorado, USA.
Insights
Cardiovascular events, including myocarditis, can occur during immune checkpoint inhibitor (ICI) therapy. While International Classification of Diseases (ICD) codes accurately identify venous thromboembolic events and myocardial infarctions, they are less reliable for heart failure and myocarditis.
Area of Science:
- Cardiology
- Oncology
- Immunology
Background:
- Immune checkpoint inhibitors (ICIs) are increasingly used for cancer treatment.
- There is a recognized risk of cardiovascular (CV) events, including myocarditis, associated with ICI therapy.
- Real-world data on the true incidence of CV events in patients with pre-existing CV disease treated with ICIs are limited.
Purpose of the Study:
- To determine the occurrence of CV events in patients undergoing ICI therapy.
- To evaluate the diagnostic accuracy of International Classification of Diseases (ICD) codes compared to expert adjudication for CV events.
- To assess the reliability of ICD codes for specific CV events like myocarditis and heart failure.
Main Methods:
- Retrospective analysis of 1,813 patients treated with ICIs at the University of Colorado Health system.
- Extraction of electronic medical records to identify potential CV events.
- Independent adjudication of CV events by two cardiologists using standardized definitions and comparison with ICD codes.
Main Results:
- The most frequent events were venous thromboembolic events (VTEs), occurring in 11.4% pre-ICI and 11.3% post-ICI therapy.
- Post-ICI therapy, myocardial infarction (MI) occurred in 3.0%, heart failure in 2.8%, and stroke in 1.6% of patients.
- Myocarditis was diagnosed in 0.3% of patients post-ICI. ICD code agreement was high for VTE (κ=0.82) and MI (κ=0.74), but lower for myocarditis (κ=0.50) and heart failure (κ=0.47).
Conclusions:
- ICD codes demonstrate good agreement with adjudicated diagnoses for VTE and MI in ICI-treated patients.
- Diagnostic accuracy of ICD codes is less reliable for heart failure and myocarditis.
- Standardized adjudication is crucial for accurately assessing the incidence of CV events related to ICI therapy.
Background:
There is growing recognition of the risk of cardiovascular (CV) events, particularly myocarditis, in the context of immune checkpoint inhibitor (ICI) therapy; however, true event rates in real-world populations and in the background of CV disease remain uncertain.
Objectives:
The authors sought to determine CV event occurrence in ICI-treated patients and assess the accuracy of diagnosis by International Classification of Diseases (ICD) code compared with adjudication using established definitions and full-source documentation review.
Methods:
Electronic medical record extraction identified potential CV events in ICI-treated patients in the University of Colorado Health system. Two cardiologists independently adjudicated events using standardized definitions. Agreement between ICD codes and adjudicated diagnoses was assessed using the kappa statistic.
Results:
The cohort comprised 1,813 ICI-treated patients with a mean follow-up of 4.6 ± 3.4 years (3.2 ± 3.2 years pre-ICI and 1.4 ± 1.4 years post-ICI). Venous thromboembolic events (VTEs) were the most common event, occurring in 11.4% of patients pre-ICI and 11.3% post-ICI therapy. Post-ICI therapy, the crude rates of myocardial infarction (MI), heart failure, and stroke were 3.0%, 2.8%, and 1.6%, respectively. Six patients (0.3%) developed myocarditis post-ICI. Agreement between the ICD code and adjudication was greater for VTE (κ = 0.82; 95% CI: 0.79-0.85) and MI (κ = 0.74; 95% CI: 0.66-0.82) and worse for myocarditis (κ = 0.50; 95% CI: 0.20-0.80) and heart failure (κ = 0.47; 95% CI: 0.40-0.54).
Conclusions:
ICD codes correlated well with adjudicated events for VTE and MI, but correlation was worse for heart failure and myocarditis. Adjudication with standardized definitions can enhance the understanding of the incidence of CV events related to ICI therapy.
Related Concept Videos
01:27Psychoneuroimmunology: Cardiovascular Disease
A key area of focus in PNI is the relationship between stress and coronary...
01:14Myocarditis III: Medical Management
01:21Rheumatic Heart Disease III: Medical Management
01:26Coronary Artery Disease IV: Preventive Measures
01:27Tumor Immunotherapy
01:17Pericarditis III: Medical Management