EDMONTON, Canada ‑ Readings from home blood pressure monitors are inaccurate 70% of the time, according to results of a recent study by researchers at the University of Alberta.
“High blood pressure is the No. 1 cause of death and disability in the world,” said Jennifer Ringrose, who led the research study, in a statement. “Monitoring for and treating hypertension can decrease the consequences of this disease. We need to make sure that home blood pressure readings are accurate.”
Results of the study were published recently in the American Journal of Hypertension.
The researchers tested several dozen home blood pressure monitors and found they were inaccurate within five mmHg about 70% of the time, and were inaccurate by 10 mmHg about 30% of the time.
The study examined the results of 85 patients. Researchers compared the results of the participants’ home monitors with the “gold standard” of two observers taking several blood pressure measurements simultaneously, blinded to one another, with a third person ensuring agreement between both observers’ readings. The majority of individual devices showed clinically-relevant inaccuracy. The team also found that readings were more inaccurate in men than in women.
The researchers advised patients who are instructed by their physician to monitor their blood pressure through a device at home to take several readings and compare them.
The researchers said that arm shape, arm size, the stiffness and age of blood vessels and the type of blood pressure cuff are not always considered when a blood pressure machine is designed and validated, said Raj Padwal, study co-author, in a statement.
They said a greater effort needs to be made among industry and academia to develop more accurate devices.