Nearly 50% of older U.S. adults reported taking aspirin preventively

A recent study found that nearly half of U.S. adults ages 60 years and older reported preventive aspirin use.

Researchers used data from the National Health and Nutrition Examination Survey from 2011 to 2018 to determine older U.S. adults' use of aspirin for primary or secondary cardiovascular disease (CVD) prevention by age, sex, and CVD risk category. The study included survey respondents ages 60 years and older, some with and some without diabetes. The researchers classified respondents as having diabetes if they self-reported a physician diagnosis of diabetes and/or use of a glucose-lowering medication. The main outcome was participants' self-reported use of low-dose aspirin therapy (including sometimes), based on their physician's advice or their own decision to help prevent heart attacks, stroke, or cancer. Schedule, frequency, and aspirin dose data were not uniformly available. Results were published on June 21 by JAMA Network Open.

A total of 7,103 individuals (mean age, 69.6 years; 45.2% men; 75.8% White) responded to the questionnaire. Overall, 46.7% of the older adults reported aspirin use, 61.7% of those with diabetes and 42.2% of those without. Among respondents with diabetes, the likelihood of aspirin use in older versus younger age categories did not differ in a model adjusted for race, sex, education, CVD risk category, and body mass index. In contrast, among those without diabetes, the same model found that aspirin use was significantly greater in older age categories (odds ratios [ORs], 1.50 [95% CI, 1.23 to 1.83] for those ages 70 to 79 years and 1.59 [95% CI, 1.24 to 2.04] for those ages 80 years and older, both compared to ages 60 to 69 years; P<0.001 for trend). The likelihood of aspirin use for primary prevention in those at high versus low risk for CVD did not differ significantly among older adults with diabetes in the model (OR, 1.69; 95% CI, 0.65 to 4.39) but did in those without diabetes (OR, 2.46; 95% CI, 1.63 to 3.71). In the same adjusted model, women were less likely to use aspirin than men, particularly among those with diabetes (OR, 0.63; 95% CI, 0.48 to 0.83).

The results suggest potential overuse of aspirin for primary prevention, with an estimated 9.9 million U.S. adults ages 70 years and older taking aspirin if it is not actively discontinued, the study authors said. Among other limitations, variables including aspirin use and diagnosis of diabetes were based on self-reported data, which could have led to misclassification, the authors noted. They added that they could not exclude the possibility that respondents who reported taking glucose-lowering medications may have included those with prediabetes who were misclassified into the diabetes group.

For many individuals in the analysis, particularly those older than age 70 years with low CVD risk, aspirin may pose a higher risk for adverse events than improved health outcomes, an accompanying editorial noted. “Despite the concern that stopping medication may lead to worse outcomes, low-dose aspirin therapy, like all medications used by older individuals, should be regularly reviewed, and the ongoing safety and need for use should be discussed. … Only through careful, ongoing assessments can physicians make sure they are following what many consider to be the most important ethical tenet of clinical care—primum non nocere—first, do no harm,” the editorialist wrote.