Program Profile

Evaluation of a Pharmacist-Driven Ambulatory Aspirin Deprescribing Protocol

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Background: Recent guidelines indicate that aspirin affords less cardiovascular protection and greater bleeding risks in adults aged > 70 years. Deprescribing potentially inappropriate medications is particularly important in older adults, as this population experiences a high risk of adverse effects and polypharmacy. Limited data are available regarding targeted aspirin deprescribing approaches by pharmacists. The objective of this study was to implement and evaluate the success and feasibility of a pharmacist-led aspirin deprescribing protocol for older adults in a primary care setting.

Observations: This prospective feasibility study in a US Department of Veterans Affairs ambulatory care pharmacy setting included veteran patients aged ≥ 70 years with documented aspirin use. We reviewed 459 patient records and determined that 110 were eligible for deprescribing. A pharmacist-initiated telephone call was attempted for each eligible patient to discuss the risks and benefits of deprescribing aspirin. The primary outcome was the proportion of patients reached for whom aspirin was discontinued. Secondary outcomes included patient rationale for declining deprescribing and the time to complete the intervention. Of 94 patients reached, 45 (48%) agreed to aspirin deprescribing, 3 (3%) agreed to dose reduction, and 29 (31%) declined the intervention. An additional 17 (18%) had previously stopped aspirin, which led to a medication reconciliation intervention. Pharmacists spent about 2 minutes per record review and 12 minutes on each encounter, including documentation.

Conclusions: Implementing a pharmacist-driven aspirin deprescribing protocol in a primary care setting led to the discontinuation of inappropriate aspirin prescribing in nearly half of older adults contacted. The protocol was well accepted by collaborating physicians and feasible for pharmacists to implement, with potential for further dissemination across primary care settings.



The use of low-dose aspirin for the primary prevention of cardiovascular disease (CVD) morbidity and mortality continues to be controversial, particularly for older adults. Recently published, robust randomized controlled trials have revealed less cardiovascular benefit from aspirin for primary prevention compared with previous trials; additionally, an increased risk of major bleeding events has been notably more prevalent in older adults.1-5 These trials have suggested that preventative aspirin use in older adults confers less benefit than other therapies for decreasing atherosclerotic CVD (ASCVD) risk, including blood pressure (BP) control, cholesterol management, and tobacco cessation.1,6

A recent meta-analysis indicated a composite cardiovascular risk reduction in patients aged 53 to 74 years taking aspirin vs no aspirin; however, this benefit was offset with an even greater increased risk of major bleeding.7 This trend was consistent regardless of stratification by 10-year ASCVD risk or presence of diabetes mellitus (DM) diagnosis.7,8 Additionally, the recently published Aspirin in Reducing Events in the Elderly (ASPREE) trial studied the impacts of aspirin use in healthy adults aged ≥ 70 years and aged ≥ 65 years among Black and Hispanic adults.4 The study concluded that the risk of major bleeding with aspirin use was even higher vs the potential cardiovascular benefit in older adults.4

With this emerging evidence, guidelines have been updated to represent the need for risk vs benefit considerations regarding aspirin use for primary prevention in older adults.1,9,10 The most recent guideline update from the American College of Cardiology and American Heart Association (ACC/AHA) recommends against the routine use of aspirin in patients aged > 70 years or those with bleeding risk factors.1 The guideline recommends considering aspirin use for patients ages 40 to 70 years only after a patient-specific risk vs benefit discussion.1 Furthermore, the 2020 American Diabetes Association guideline recommends considering aspirin use for primary prevention in adults with DM between ages 50 and 70 only after a risk vs benefit discussion of patient-specific bleeding risk factors and ASCVD risk-enhancing factors.10

Despite the demonstrated risks for bleeding with the routine use of aspirin, studies indicate that aspirin continues to be used commonly among older adults, often when unnecessary. In the 2017 National Health Interview Survey, about 23% of adults aged > 40 years in the United States without CVD used aspirin daily, and 23% of these did so without recommendation from a health care professional.11 Furthermore, nearly half of adults ages ≥ 70 years and nearly one-quarter of adults with a history of peptic ulcer disease used aspirin daily.11 Although the most recent guidelines from the ACC/AHA do not recommend a 10-year ASCVD risk threshold for therapy, one study illustrated that 12% of older adult patients were inappropriately prescribed aspirin for primary prevention despite a 10-year ASCVD risk of < 6%.1,12 These studies highlight the large proportion of individuals, particularly older adults, who may be inappropriately taking aspirin for primary prevention.

Deprescribing Program

Deprescribing potentially inappropriate medications (PIMs) is particularly important in the older adult population, as these individuals experience a high risk of adverse effects (AEs), polypharmacy, cognitive decline, and falls related to medication use.6,13-17 Evidence suggests that mortality outcomes are improved with the implementation of targeted deprescribing efforts based on patient-specific factors.18 Additionally, deprescribing unnecessary medications may improve adherence to other essential medications and reduce financial burdens.19 Pharmacists play a crucial role among health care professionals in the implementation of deprescribing practices, and studies have shown that physicians are highly accepting of pharmacists’ deprescribing recommendations.13,20-22

Despite the evidence for the benefits of deprescribing, limited data are available regarding the impact and feasibility of a targeted aspirin deprescribing approach by nonphysician practitioners.23 The objective of this study was to implement and evaluate the success of a pharmacist-driven aspirin deprescribing protocol for older adults in a primary care setting.

This aspirin deprescribing protocol was developed by ambulatory care clinical pharmacist or clinical pharmacist practitioners (CPPs), at the William S. Middleton Memorial Veterans Hospital in Madison, Wisconsin. Within the US Department of Veterans Affairs (VA) health care system, CPPs work under a broad scope of practice with the ability to independently prescribe and monitor medications. The protocol was reviewed by physician stakeholders in both primary care and cardiology and a list was generated, including patients from 2 primary care panels aged ≥ 70 years with aspirin on their medication list, either as a prescription or over-the-counter medication, using the VA Information System Technology and Architecture. A CPP or supervised pharmacy intern identified patients from this list who were appropriate for risk/benefit discussions regarding the discontinuation of aspirin. Patients were excluded from the intervention if they had a history of clinical ASCVD, including myocardial infarction (MI), stable or unstable angina, coronary artery disease (CAD), coronary or other arterial revascularization, cerebrovascular accident (CVA), transient ischemic accident (TIA), or peripheral artery disease (PAD), or another documented indication for aspirin use, including pain, flushing (with niacin use), venous thromboembolism prophylaxis, valvular heart disease, or acute or recurrent pericarditis.

After identifying eligible patients, a CPP or pharmacy intern contacted patients by telephone, following a script to guide conversation. All patients were screened for potential appropriate aspirin indications, particularly any history of MI, CAD, CVA, TIA, PAD, or other clinical ASCVD. The patient was asked about their rationale for taking aspirin and patient-specific ASCVD risk-enhancing factors and bleeding risk factors and educated them on lifestyle modalities to reduce ASCVD risk, using the script as a guide. ASCVD risk-enhancing factors included family history of premature MI, inability to achieve BP goal, DM with the inability to achieve blood glucose or hemoglobin A1c goal, tobacco use, or inadequate statin therapy. Bleeding risk factors included a history of gastrointestinal bleed or peptic ulcer disease, concurrent use of medications that increase bleeding risk, chronic kidney disease, or thrombocytopenia.


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