Patient Satisfaction and Out-of-Pocket Costs Associated With Aspirin and Low-Molecular-Weight Heparin: A Secondary Analysis of the PREVENT CLOT study

Friday, October 20, 2023

2:31 PM – 2:37 PM PST

Location: 4B

Presenting Author / Corresponding Author(s)

Nathan N. O'Hara, PhD

Assistant Professor
University of Maryland School of Medicine, R Adams Cowley Shock Trauma Center
Baltimore, Maryland, United States

Disclosure(s): Arbutus Medical Inc.: Stock Shareholder (excluding mutual funds) (Ongoing)

Co-Author(s)

DS

Deborah Stein, MD, MPH

Professor
Department of Surgery, University of Maryland School of Medicine
KF

Katherine Frey, PhD (she/her/hers)

Associate Scientist
Johns Hopkins University Bloomberg School of Public Health
Johns Hopkins University
Baltimore, Maryland, United States
JL

Joseph F. Levy, PhD
GS

Gerard P. Slobogean, MD

Associate Professsor
University of Maryland School of Medicine, R Adams Cowley Shock Trauma Center
Baltimore, Maryland, United States
RC

Renan C. Castillo, PhD

Professor
Johns Hopkins Bloomberg School of Public Health
Baltimore, Maryland, United States
Reza Firoozabadi, MD, MA

Associate Professor of Orthopedics and Sports Medicine
University of Washington, Harborview Medical Center
Seattle, Washington, United States
MK

Madhav A. Karunakar, MD

Atrium Health Carolinas Medical Center
Joshua L. Gary, MD

Chief of Orthopaedic Trauma Service
Keck School of Medicine of the University of Southern California
Los Angeles, California, United States
William T. Obremskey, MD, MPH, FIOTA (he/him/his)

Director Orthopedic Trauma Fellowship and Research
Vanderbilt University Medical Center
Vanderbilt Ortho Inst
Nashville, Tennessee, United States
RS

Rachel B. Seymour, PhD

Vice Chair of Research and Professor
Atrium Health Carolinas Medical Center
Charlotte, North Carolina, United States
RO

Robert V. O'Toole, MD

Professor, Orthopaedic Surgery
University of Maryland School of Medicine, R Adams Cowley Shock Trauma Center
Baltimore, Maryland, United States

Group Author(s)

GM

Group METRC

Purpose: We aimed to determine if the type of thromboprophylaxis affected patients’ medication satisfaction and out-of-pocket costs after orthopaedic trauma. We hypothesized that patients treated with aspirin would have increased medication satisfaction and lower out-of-pocket costs.

Methods: This was a prespecified secondary analysis of PREVENT CLOT, a randomized clinical trial performed at 21 trauma centers in the US and Canada. We included adult patients with an operatively treated extremity fracture or a pelvis or acetabulum fracture, treated operatively or nonoperatively. Patients were randomly assigned to 30 mg low-molecular-weight heparin (enoxaparin) or 81 mg aspirin, twice daily. The duration of thromboprophylaxis was based on existing hospital protocols. Our main outcomes were patient satisfaction and out-of-pocket costs. We measured patients’ thromboprophylaxis satisfaction using a 7-point Likert scale adapted from the Treatment Satisfaction Questionnaire for Medication. Patients reported their total out-of-pocket costs associated with thromboprophylaxis 90 days after injury. We estimated treatment effects using cumulative logit and logistic regression models.

Results: A total of 9115 patients completed the medication satisfaction question, and 6723 patients reported their out-of-pocket costs. The mean age was 44 years (standard deviation [SD] 17), and 88% had a lower extremity fracture. The odds of greater medication satisfaction were 2.6 times higher for patients assigned to aspirin than those assigned to low-molecular-weight heparin (odds ratio [OR], 2.59; 95% confidence interval [CI]: 2.39 to 2.80; P<0.001). Overall, the odds of incurring any out-of-pocket costs for thromboprophylaxis medication were 51% higher for patients assigned to aspirin compared to low-molecular-weight heparin (OR, 1.51; 95% CI: 1.37 to 1.66; P<0.001). However, patients assigned to aspirin had substantially lower odds of out-of-pocket costs exceeding $25 (OR, 0.15; 95% CI, 0.12 to 0.18; P<0.001).

Conclusion: Among orthopaedic trauma patients, aspirin substantially improved medication satisfaction. While aspirin increased the odds of incurring any out-of-pocket costs, it protected against costs exceeding $25, possibly improving health equity for thromboprophylaxis. These data should be considered by patients, health-care systems, and clinicians when prescribing thromboprophylaxis for orthopaedic trauma patients.