Over-The-Counter Aspirin Use In Patients Diagnosed With Multiple Myeloma

Patients with multiple myeloma (MM) are at increased risk for venous thromboembolism (VTE) due to patient, disease, and treatment-related factors. Current National Comprehensive Cancer Network (NCCN) guidelines for VTE suggest that patients with MM receiving thalidomide or lenalidomide in combination with high-dose dexamethasone (480 mg per month) receive VTE prophylaxis. For MM patients at high risk for VTE (≥2 risk factors), low molecular weight heparin or full-dose warfarin is recommended. For MM patients at low risk for VTE (0-1 risk factor), aspirin 81-325 mg once daily is recommended for VTE prophylaxis. Eighty-five percent of patients diagnosed with MM are aged ≥55 and many of them are prescribed aspirin for primary or secondary prevention of cardiovascular or cerebrovascular disease, independent of their MM diagnosis. According to the 2010 National Health Interview survey, the prevalence of regular aspirin use among persons in the United States ≥50 years of age is 35.9%. Because aspirin use may provide effective prophylaxis of venous events in MM patients at low risk for VTE, it is important to understand the prevalence of aspirin use among MM patients.

As part of a larger study examining the risk of VTE among patients diagnosed with MM and treated with thalidomide or lenalidomide, the objective of this study was to estimate the prevalence of over-the-counter (OTC) aspirin use among MM patients.

Patients ≥18 years of age diagnosed with MM between January 1, 2005 and September 30, 2012 were identified from the tumor registry at the Henry Ford Health System (HFHS), a large integrated health care delivery system located in southeastern Michigan; whose data are included in the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. We developed a telephone survey, and then contacted all eligible patients (i.e. they were alive and/or not documented as deceased) to quantify OTC aspirin use. Data analyses included descriptive statistics to assess the demographic, clinical, and aspirin use characteristics.

We identified 381 patients diagnosed with MM; of those, 177 were eligible for the survey. We contacted these patients and achieved a 67% (n=119) response rate.

The median age of survey respondents was 64 years (range 41-93) and 93 (78%) were aged ≥55. Sixty-two (52%) of the survey responders were female, 82 (69%) were African American, and 36 (30%) were white.

Of the respondents, 46 (39%) reported weekly aspirin use and 43 of the 46 (94%) reported daily aspirin use. The average daily dose was 114 mg/day (standard deviation 93) and most patients (n=39 of 46; 85%) reported taking an 81 mg dose.

The reason for daily aspirin use was cited as “Other reason for prophylaxis” by 36 (of 43; 84%) of the patients. In this case, patients indicated that they were taking aspirin for prophylaxis, but did not provide enough information to determine the reason for daily aspirin use. Only 5 patients (12%) reported taking aspirin for heart disease prophylaxis.

Roughly one-quarter of the MM patients (n=31 of 119; 26%) indicated that they had a health problem that made aspirin use unsafe. Twenty-seven (23%) reported that they had a parent or sibling who had a heart attack before the age of 60; fourteen patients (12%) reported that they had a parent or sibling who has or ever had a VTE. Seventeen patients (14%) reported a history of ever having a VTE event themselves.

Our data indicate that over one-third of patients diagnosed with MM use OTC aspirin daily. When treating patients diagnosed with MM, assessing risk for VTE and determining an appropriate VTE prophylaxis therapy is of the utmost importance.