Association Between Use of WATCHMAN Device and 1-Year Mortality Using High-Dimensional Propensity Scores to Reduce...

Area of Science:

• Cardiology
• Medical Informatics
• Epidemiology

Background:

• Observational studies suggested WATCHMAN device (percutaneous left atrial appendage occlusion [pLAAO]) reduced mortality, contrasting with randomized controlled trial (RCT) evidence.
• Discrepancies highlight the need for advanced statistical methods in comparative effectiveness research.

Purpose of the Study:

• To compare 1-year mortality between patients with atrial fibrillation receiving pLAAO versus direct oral anticoagulants (DOACs).
• To evaluate the utility of high-dimensional propensity score (hdPS) in refining non-active comparator selection for observational studies.

Main Methods:

• Two matched cohorts were created using Medicare data (2011-2018).
• Cohort 1: Traditional propensity score (PS) matching.
• Cohort 2: Integrated traditional PS with hdPS, excluding cancer patients and including frailty scores.

Main Results:

• In Cohort 1 (PS matching), pLAAO showed a hazard ratio (HR) of 0.87 (95% CI, 0.69-1.09) for 1-year mortality.
• In Cohort 2 (hdPS-enhanced), pLAAO showed an HR of 0.95 (95% CI, 0.73-1.24) for 1-year mortality.
• Both cohorts demonstrated no significant difference in 1-year mortality between pLAAO and DOACs.

Conclusions:

• pLAAO is not associated with a different 1-year mortality risk compared to DOACs in this real-world data analysis.
• The hdPS methodology offers a valuable tool for improving patient selection and reducing bias in observational comparative effectiveness studies.