A146 MANAGEMENT OF ANTITHROMBOTIC THERAPY AFTER GASTROINTESTINAL BLEEDING: A MIXED METHODS STUDY OF HEALTHCARE PROVIDERS

Background

Oral anticoagulants (OAC) are permanently discontinued in up to 50% of patients after gastrointestinal (GI) bleeding despite ongoing thrombotic risk and evidence of benefit to restarting. The reasons for permanent discontinuation of OAC are unclear, but likely include concerns about re-bleeding and a lack of high-quality evidence. There are no studies evaluating healthcare provider values and preferences following OAC-related GI bleeding and their influence on decision-making about whether and when to resume OACs.

Aims

We aimed to (i) identify key factors (attributes) that influence healthcare provider decision-making regarding resumption of OAC after GI bleeding, (ii) determine the relative importance of these attributes, and (iii) to identify preference groups.

Methods

We conducted focus group discussions (FGD) with healthcare providers involved in the care of patients with OAC-related GI bleeding. Participants ranked the relative importance of the attributes identified during the FGD through a dot voting exercise. Transcripts were reviewed and themes (attributes) were identified. Results of the FGD informed a discrete choice experiments survey developed and analyzed using the Sawtooth software platform (Sawtooth Software, USA). The survey was pilot tested and modified by iterative feedback. A sample choice task is shown in Image 1. Hierarchical Bayes analysis was used to estimate preference coefficients (utilities) for each attribute. Latent class analysis was used to identify preference groups.

Results

There were 4 FGD involving 29 participants. The most important attributes identified and included in the survey were thrombosis risk, indication for OAC, index bleed severity, re-bleeding risk, and patient characteristics. There were 130 survey respondents practicing in hematology (n=68), internal medicine (n=30), gastroenterology (n=7), cardiology (n=4), family medicine (n=3), and others (n=18). The mean age was 45 years (±11) and 51% were male. Thrombosis risk and re-bleeding risk equally had the highest utility followed by index bleed severity, patient characteristics, and indication for OAC. Two preference groups were identified. The dominant preference group (78% of respondents) placed the highest utility on thrombosis risk and re-bleeding risk, while a minority (22% of respondents) placed the highest utility on index bleed severity.

Conclusions

Thrombosis risk and re-bleeding risk are equally the most important factors influencing OAC resumption following OAC-related GI bleeding. The severity of the index bleed is the most important factor in decision-making for a minority segment of healthcare providers. Further research on the dose, type and timing of OAC resumption is needed to determine the optimal balance between thrombosis and re-bleeding.

Funding Agencies

Heart and Stroke Foundation

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