Utility of ICD Codes for Stress Cardiomyopathy in Hospital Administrative Databases: What Do They Signify?

Area of Science:

• Cardiology
• Medical Informatics

Background:

• Administrative databases are crucial for medical research.
• International Classification of Diseases (ICD) codes are frequently used to identify patients with specific conditions, such as stress cardiomyopathy (SCM).
• The accuracy and completeness of ICD code-based SCM identification in administrative data require validation.

Purpose of the Study:

• To evaluate the validity of International Classification of Diseases (ICD) codes for identifying patients with stress cardiomyopathy (SCM) in administrative databases.
• To assess the clinical presentation and diagnostic workup of SCM patients identified via ICD codes.

Main Methods:

• Retrospective chart review of patients discharged with an ICD code for SCM between 2010 and 2016.
• Calculation of the positive predictive value (PPV) of ICD codes for SCM diagnosis.
• Analysis of clinical manifestations and diagnostic procedures (cardiac catheterization, echocardiography) in identified SCM patients.

Main Results:

• A high positive predictive value (98%) was found for ICD codes in identifying SCM.
• A small proportion (6.4%) of patients with an SCM ICD code did not present with active clinical manifestations during hospitalization.
• Inconsistent diagnostic workup was observed, with only 66.8% undergoing cardiac catheterization and 91.5% undergoing echocardiography.

Conclusions:

• ICD codes are largely accurate for identifying SCM diagnoses in administrative databases.
• Limitations include the presence of chronic SCM cases and incomplete diagnostic workups in some patients.
• Researchers utilizing administrative data for SCM studies must be aware of these potential biases and limitations.