Too-tight blood pressure cuffs can cause “strikingly inaccurate” readings and a misdiagnosis of hypertension for adults with larger arms, a Johns Hopkins University study has found.
Six Johns Hopkins researchers published the study Monday in JAMA Internal Medicine. They examined 195 adults from Baltimore with a mean age of 54 and a range of arm sizes who volunteered for four sets of blood pressure readings using too-small, too-large and appropriately sized cuffs.
The study found participants with smaller arms got a 3.6 millimeters of mercury lower systolic blood pressure reading from the regular-sized cuff used in many doctors’ offices and home blood pressure machines than from their correct size.
Adults requiring a large or extra-large cuff had 4.8 mm Hg and 19.5 mm Hg higher blood pressure readings from the regular cuff, respectively, than from their correct sizes.
“Many office triage measurements occur without individualized cuff selection, and most home [blood pressure] devices come with one cuff size,” Dr. Tammy Brady, co-author of the study and director of the pediatric hypertension program at Johns Hopkins Children’s Center, told newsfeedworld.
Earlier studies didn’t quantify the impact of the wrong cuff sizes on blood pressure readings and related diagnoses, she noted.
In the most striking example from the study, participants who required an extra-large cuff measured their blood pressure at an average of 125/79 with the right-sized cuff, an elevated reading. When the same adults used a regular-sized cuff that was two sizes too small, they scored an average blood pressure reading of 144/87, a stage two hypertension reading.
According to other data cited in the study, only 74% of medical students under observation chose the right cuff size for measurements.
The researchers urged doctors, nurses and adults measuring their blood pressure at home to pay closer attention to the cuffs they use, especially for people with larger arms who could get misdiagnosed with stage one or two hypertension.
“Individuals with an incorrect hypertension diagnosis could experience undue stress, incur expense, undergo unnecessary testing and receive overtreatment, which could lead to side effects and adverse events,” Dr. Brady said. “Conversely, when a loo-large cuff is used, hypertension could be missed, leading to missed opportunity for treatment and prevention of [cardiovascular disease].”
