Home Blood Pressure Monitors May Not Fit 18 Million U.S. Adults, Study Finds

Research presented at the American Heart Association's Hypertension Scientific Sessions 2024 indicates that the arm cuffs of many popular at-home blood-pressure monitors may not fit up to 18 million adults in the United States, with nearly 12% of Black adults affected. This issue raises significant concerns about the accuracy of blood pressure readings, which are crucial for diagnosing and managing hypertension.

The study, published in the journal Hypertension, highlights the need for manufacturers and retailers to address these disparities by offering a wider range of cuff sizes. Accurate blood pressure monitoring is essential, as nearly half of U.S. adults have been diagnosed with high blood pressure, a condition that can lead to severe health complications such as heart attack, stroke, and heart failure.

Researchers found that most of the tested devices were designed to fit arm circumferences between 8.7 to 16.5 inches. This standard sizing excludes approximately 18 million U.S. adults whose arm circumferences fall outside this range, potentially providing inaccurate blood pressure measures. The disparity is particularly pronounced among Black adults, with 11.8% affected compared to 6.6% of white adults, 5.2% of Hispanic adults, and 1.8% of Asian adults.

Senior study author Kunihiro Matsushita, M.D., Ph.D., FAHA, emphasized the importance of addressing this issue for better hypertension diagnosis and management. “To increase equity, manufacturers should prioritize the development and affordable sale of blood pressure measuring devices that accommodate arm circumferences greater than 42 centimeters, and health care professionals should measure patients’ arm circumferences to help them select an appropriate cuff size when purchasing a home blood pressure device,” Matsushita stated.

The study utilized data from the U.S. National Health and Nutrition Examination Survey (NHANES) from 2015-2020 and extrapolated it to the 2023 U.S. Census data. Participants' average age was 47 years, with 51% identifying as women and 49% as men. The research also noted that the number of U.S. adults with an arm size larger than routinely covered by the manufacturer-provided cuff size (16.5 million) was significantly higher than those with an arm size smaller than the standard coverage (0.8 million), indicating a higher likelihood of hypertension overestimation.

Paul K. Whelton, M.B., M.D., M.Sc., FAHA, commented on the study’s findings, stating that the use of an incorrectly sized cuff is a major source of systematic error in blood pressure measurement. “The best solution is to have cuffs of different sizes available, so a cuff that is of correct size for the patient can be chosen,” he said.

The study’s limitations include its focus on a single large online retailer and only 10 devices. Despite these constraints, the findings underscore the critical need for improved design and accessibility of blood pressure monitors, especially for populations at higher risk of hypertension.

This research points to a significant gap in the market for blood pressure monitoring devices and calls for immediate action from manufacturers and healthcare providers to ensure accurate and equitable health outcomes for all individuals.