Over-the-counter blood pressure monitors provide an easy and cost-effective method for individuals to manage hypertension from home. However, a recent study indicates that the standard arm-size ranges for these devices fail to fit millions of consumers in the U.S., as per a new investigation by researchers at the Johns Hopkins Bloomberg School of Public Health.
Over-the-counter blood pressure measuring devices offer a simple, affordable way for people to track hypertension at home, but the standard arm-size ranges for these devices won’t appropriately fit millions of U.S. consumers, according to a new study from researchers at the Johns Hopkins Bloomberg School of Public Health.
The study team analyzed the typical arm cuff sizes for widely used retail automatic blood pressure monitors and compared these to arm measurements gathered from national health surveys funded by the U.S. government.
Their findings revealed that roughly 6.7 percent of U.S. adults — about 17.3 million people — have arms that don’t conform to standard cuff sizes. For most of these individuals — 6.4 percent, or around 16.5 million — the cuffs would be too small. The issue is more prominent among Black adults, with nearly 12 percent falling outside the acceptable arm size for standard cuffs.
Using an improper cuff can lead to significant inaccuracies in blood pressure readings and can hinder individuals from effectively tracking their blood pressure altogether.
The results of the study were published on September 5 in the journal Hypertension and will be presented on September 6 at the American Heart Association’s annual Hypertension meeting in Chicago.
“The fact that millions of Americans are affected shows that this is not a small problem; one of the simplest solutions would be for retailers to provide a wider variety of cuff sizes at no extra cost,” states Dr. Kunihiro Matsushita, the senior author of the study and a professor in the Bloomberg School’s Department of Epidemiology.
The research’s first author, Eileen Kaur, was a high school intern in the Matsushita Laboratory during the research period.
The researchers also suggested that healthcare providers should educate patients on the importance of choosing the correct cuff size when purchasing home blood pressure monitors.
Hypertension — typically indicated by blood pressure readings consistently over 130/80 — is a significant contributor to conditions like heart disease, stroke, kidney disease, vision impairment, and dementia, making it a leading cause of premature mortality globally. Accurate blood pressure measurement is vital for effectively managing hypertension. Previous research has indicated that ill-fitting cuffs can compromise measurement accuracy.
For their study, the researchers identified 16 widely used automatic blood pressure monitors in early January 2024, based on recent customer reviews and sales data. They purchased 10 devices for testing (some were unavailable; others lacked arm cuffs). The research team then analyzed the cuff sizes of these devices against arm circumference data from a sample of 13,826 American adults from the U.S. National Health and Nutrition Examination Surveys (NHANES) conducted between 2015 and 2020.
Nine of these devices offered cuffs that accommodated arm circumferences ranging from 22 to 42 centimeters (8.6 to 16.5 inches), while one device had a cuff measuring from 22 to 40 centimeters (8.6 to 15.7 inches). The NHANES data indicated that 6.7 percent of U.S. adults, equating to 17.3 million individuals based on 2023 Census data, have arm circumferences outside of these ranges — 0.3 percent with sizes below 22 centimeters (8.6 inches) and 6.4 percent above 42 centimeters (16.5 inches), the latter representing approximately 16.5 million adults.
The NHANES data also highlighted racial and ethnic disparities, indicating that 11.8 percent of Black adults have arm sizes outside the standard range, a figure significantly higher than the national average. This is a particular concern, Matsushita points out, because Black adults exhibit a notably higher incidence of hypertension compared to other racial or ethnic groups: 57.1 percent for Black adults versus 43.6 percent for white adults and 43.7 percent for Hispanic adults.
Some of the devices assessed in the research did provide cuff sizes beyond the standard range, but these were available only as separate accessories that required extra purchase after acquiring the basic model. The researchers recommend that manufacturers should instead provide a variety of cuff sizes as part of their standard offerings.
“Consumers should have the same ease of access to appropriate blood pressure cuff sizes as they do with clothing sizes,” Matsushita adds.
Even a slight expansion of the current cuff size range from 20 centimeters (8.6 inches) to encompass sizes between 25 and 45 centimeters (9.8 to 17.7 inches) would greatly enhance coverage of diverse arm sizes among Americans, the researchers suggest.
