July 24, 2025JACC Advances1 citationsOpen Access
Comparing Claims Data to Stroke and Bleeding in the NCDR Left Atrial Appendage Occlusion Registry
Key Result
Medicare claims data significantly overestimated the 2-year incidence of ischemic stroke compared to adjudicated registry data in patients undergoing left atrial appendage occlusion (2.47% vs 2.15%, HR 1.15).
Study Design
Type
Observational (n=71,043)
Multicenter
Yes
Structured PICO
How accurately do Medicare claims data identify stroke and bleeding events compared to adjudicated registry reports in patients undergoing LAAO?
P
Population
71,043 patients aged ≥65 years who underwent transcatheter left atrial appendage occlusion (LAAO) in the NCDR LAAO Registry linked to 2016-2021 Medicare claims.
I
Intervention
Medicare claims data (International Classification of Diseases-Tenth Revision codes from inpatient hospitalizations)
C
Comparator
Adjudicated registry-reported events
O
Outcome
Agreement (sensitivity, positive predictive value, kappa statistics) and incidence rates of stroke and major bleeding events after dischargehard clinical
Claims data have only moderate agreement with adjudicated registry events for stroke and bleeding after LAAO, generally overestimating event rates, highlighting the need for nonclaims-based surveillance.
Main Result
Effect estimate: HR 1.15 (95% CI 1.05-1.26)
Absolute Event Rate: 2.47% vs 2.15%
p-value: p=0.002
Limitations
- Only included patients with atrial fibrillation who underwent LAAO, limiting generalizability to the general population.
- Only included patients enrolled in Medicare fee-for-service, excluding Medicare Advantage or commercial insurance.
- Limited to ICD-10 codes from inpatient hospitalizations, potentially missing less severe events from emergency department visits or observation stays.
- Registry events may have been missed if not reported at follow-up visits.
- A clinical events committee did not manually review all site-reported events.
Abstract
BACKGROUND: Claims data are increasingly used for postmarketing surveillance of therapies such as transcatheter left atrial appendage occlusion (LAAO), but their accuracy remains uncertain. OBJECTIVES: This study aimed to compare stroke and bleeding events in the National Cardiovascular Data Registry LAAO Registry with claims data. METHODS: LAAO Registry data for patients aged ≥65 years were linked to 2016 to 2021 Medicare claims. Primary diagnosis International Classification of Diseases-Tenth Revision codes from inpatient hospitalizations were compared to adjudicated registry-reported stroke and major bleeding events after discharge, including estimation of sensitivity and positive predictive value of claims for identifying registry-reported events. Kappa statistics and incidence rates were also assessed. RESULTS: Among 71,043 LAAO Registry patients, sensitivity and positive predictive value of claims were 60.8% and 50.5% for ischemic stroke (kappa 0.55), 42.7% and 50.5% for hemorrhagic stroke (kappa 0.46), 55.9% and 40.3% for gastrointestinal bleeding (GIB) (kappa 0.43), 62.2% and 38.0% for intracranial hemorrhage (kappa 0.47), and 20.4% and 10.0% for other major bleeding (kappa 0.12). Sensitivity and negative predictive values were >92% for all events. Two-year incidence rates were higher in claims vs registry data for ischemic stroke (2.5% vs 2.2%), GIB (6.8% vs 5.2%), intracranial hemorrhage (1.6% vs 1.1%), and other bleeding (3.1% vs 1.5%; P < 0.01 for all events), and lower for hemorrhagic stroke (0.4% vs 0.5%; P = 0.03). CONCLUSIONS: In the LAAO Registry, International Classification of Diseases-Tenth Revision codes have moderate agreement with stroke, GIB, and intracranial hemorrhage, and overestimate most event rates compared to adjudicated registry-reported events. Nonclaims-based methods are needed to ensure accurate assessment of clinical events in postmarketing surveillance.