Researchers have created an innovative smartphone app capable of measuring blood pressure by utilizing the built-in sensors of smartphones, which eliminates the dependency on traditional cuffs. This new technology can significantly enhance the accessibility and convenience of blood pressure monitoring, especially for those who are underserved. By enabling users to check their blood pressure at any time and place, this app has the potential to transform cardiovascular care and enhance early detection of hypertension.
At the University of Pittsburgh, researchers are leading a novel method to monitor blood pressure by using the devices we carry daily.
Ramakrishna Mukkamala, a bioengineering professor at Pitt’s Swanson School of Engineering, is dedicated to creating easily accessible blood pressure (BP) detection tools. Rather than inventing a new medical device for blood pressure monitoring, Mukkamala decided to utilize the smartphones that most people already have, aiming to develop a way to measure blood pressure through the sensors integrated into these devices.
“One of the most crucial steps in lowering the risk of cardiovascular diseases is to manage high blood pressure through lifestyle changes, but many in underserved communities lack access to blood pressure cuffs, regular healthcare appointments, or even awareness that high blood pressure is a concern,” Mukkamala stated. “However, they do own smartphones.”
The team led by Mukkamala made use of existing smartphone tools such as motion-sensing accelerometers, front-facing cameras, and touch sensors to create a smartphone application on Android that measures an individual’s pulse pressure. Users perform a hand-raising motion while holding the phone to take their measurement. The findings from their project, titled “A smartphone application toward detection of systolic hypertension in underserved populations,” published in Scientific Reports, showcase a promising new technology that may help alleviate the global burden of systolic hypertension, particularly in underserved communities.
Creating blood pressure technology for touchscreens
Transforming a smartphone into a monitoring tool was challenging, as Vishaal Dhamotharan, a graduate student from the Cardiovascular Health Tech Laboratory, discovered through numerous app development iterations. Since smartphones lack force-sensing capabilities, a key aspect of the project involved recreating the effects of a conventional blood pressure examination using just a cell phone, which the team achieved by relying on the force of gravity.
“Thanks to gravity, there’s a change in hydrostatic pressure in your thumb when you lift your arms above your heart. By using the phone’s accelerometer, we can translate that into a relative pressure change,” Dhamotharan explained.
By combining this hand-raising action with specific thumb movements on the smartphone, the team successfully calculated each participant’s pulse pressure. Pulse pressure refers to the difference between the upper (systolic) and lower (diastolic) values — for instance, a person with a blood pressure reading of 120/80 has a pulse pressure of 40. For Sanjeev Shroff, a collaborator and chair of the bioengineering department, this publication represents a significant step forward in the realm of blood pressure measurement devices.
“Creating a cuffless blood pressure measurement tool that doesn’t require external calibration is the ultimate goal — such a device is not yet available,” Shroff noted. “The research presented in this publication is an important advancement and opens doors for further efforts to obtain systolic, diastolic, and mean pressures.”
Although pulse pressure is not typically employed in monitoring cardiovascular diseases, the research underscored its vital role as an indicator of hypertension, according to Céderick Landry, an assistant professor at the University of Sherbrooke and a former postdoctoral researcher in the lab.
“Standard guidelines usually require physicians to measure both systolic and diastolic blood pressure; pulse pressure is simply the difference between the two,” Landry mentioned. “We demonstrated that even if you only have access to pulse pressure, it still correlates strongly with hypertension, so a part of our challenge now is to shift the perspective on how best to conduct these measurements.”
Making hypertension management accessible
Systolic hypertension, or high blood pressure, impacts over 4 billion adults globally and is the primary modifiable risk factor for cardiovascular diseases, which are the leading cause of death worldwide. This app could bring blood pressure monitoring capabilities to any smartphone user, facilitating regular self-monitoring and the straightforward sharing of results with healthcare providers. This advancement holds particular promise for managing hypertension, which can often be eased through lifestyle changes such as decreasing salt intake, quitting smoking, and maintaining regular exercise.
“This app would be incredibly valuable in low-income areas where individuals may not have easy access to blood pressure monitoring tools,” Dhamotharan stated. “Being able to measure blood pressure more consistently allows a person to observe significant changes, keep an eye on hypertension, and better manage their conditions with that insight.”
With people residing in rural areas of the U.S. being 40% more likely than those in urban environments to develop heart disease, this technology could play a crucial role in providing accessible healthcare resources to communities both domestically and internationally. Looking ahead, Mukkamala and his team are focused on further refining smartphone blood pressure monitoring, aiming to ensure it reaches those who need it most.
“The research is available — we just require assistance to enhance the technology,” Landry stated. “This is the first approach of its kind, and even better, it’s something we can start implementing immediately.”
