Aspirin for DVT Prophylaxis

Primary Prophylaxis Settings

The American College of Chest Physicians (ACCP) guidelines state that aspirin is not recommended as primary DVT prophylaxis in most clinical settings, as it is significantly less effective than anticoagulants, but may be considered in select scenarios, such as low-risk orthopedic surgery patients, secondary prevention after stopping anticoagulation for unprovoked VTE, or in low-risk multiple myeloma patients 1, 2
The American College of Chest Physicians (ACCP) and the National Comprehensive Cancer Network (NCCN) guidelines advise against using aspirin as the sole method of thromboprophylaxis in hospitalized medical or surgical patients due to inferior efficacy compared to anticoagulants 3, 4
The NCCN guidelines state that aspirin is not considered effective VTE prophylaxis in general settings, with the Women's Health Study showing no significant reduction in VTE incidence over 10 years in healthy women 3, 5

The American College of Chest Physicians (ACCP) guidelines suggest using aspirin over no treatment to reduce recurrent VTE risk if a patient decides to stop anticoagulation after unprovoked proximal DVT or PE, with a weak recommendation and low-certainty evidence showing aspirin reduces recurrent VTE by 53 fewer events per 1,000 cases over 2-4 years compared to placebo 1, 2
The CHEST guidelines provide a critical caveat that aspirin is NOT a reasonable alternative to continued anticoagulation, as reduced-dose DOACs prevent 46 more VTE events per 1,000 cases compared to aspirin with similar bleeding risk 1, 2

The National Comprehensive Cancer Network (NCCN) guidelines advise against using aspirin as sole prophylaxis in high-risk patients, such as those with active cancer, prior VTE, hypercoagulable states, or prolonged immobility 3, 4

The 2021 CHEST guidelines provide direct comparisons showing anticoagulants' superiority, with reduced-dose DOAC vs aspirin resulting in 46 fewer VTE events per 1,000 cases with only 4 more bleeding events 1, 2
The 2021 CHEST guidelines also compare rivaroxaban vs aspirin, resulting in 39 fewer VTE events per 1,000 cases with 4 more major bleeds 1, 2

The American Academy of Orthopaedic Surgeons (AAOS) recommends aspirin as an acceptable sole prophylactic agent (Grade B recommendation) for standard-risk patients after hip replacement, prioritizing symptomatic outcomes over asymptomatic DVT rates detected by imaging 6
The Scottish Intercollegiate Guidelines Network (SIGN) and Brazilian guidelines also endorse aspirin monotherapy (Grade A recommendations) for standard-risk patients after hip replacement, prioritizing symptomatic outcomes over asymptomatic DVT rates detected by imaging 6
The American College of Chest Physicians (ACCP) explicitly advises against aspirin as the sole method of thromboprophylaxis (Grade A recommendation) for patients after hip replacement, stating it is significantly less effective than other anticoagulant regimens 6
The French guidelines similarly recommend against aspirin monotherapy (Grade B) for patients after hip replacement 6

Aspirin was found to be noninferior to low-molecular-weight heparin (LMWH) for extended VTE prophylaxis after initial 10 days of LMWH following total hip arthroplasty 7