A new technique has been developed to improve the accuracy of interpreting blood pressure measurements taken at the ankle, especially for individuals who cannot have their arm blood pressure measured. This innovative approach, researched by the University of Exeter Medical School and funded by the National Institute for Health and Care Research (NIHR), analyzed data from over 33,000 individuals to create a personalized predictive model for estimating arm blood pressure more effectively from ankle readings compared to existing methods. The team has also introduced an online calculator for healthcare professionals and patients to interpret these readings with precision.

High blood pressure affects more than one billion people worldwide, increasing the risk of serious health conditions like heart, brain, and kidney diseases. Accurate measurement and interpretation of blood pressure readings are crucial. While blood pressure is commonly measured on the arm, there are situations where this is not feasible due to disabilities, missing limbs, or conditions like stroke. In such cases, blood pressure can be measured at the ankle, but these readings tend to be higher than arm values. However, existing guidelines for treating blood pressure are based solely on arm readings, leading to challenges in accurately estimating based on ankle measurements and potentially resulting in misdiagnoses.

Professor Chris Clark from the University of Exeter Medical School, who led the study, emphasized the significance of the new method in providing more accurate blood pressure readings for a slightly larger percentage of individuals. Considering that a substantial number of adults have high blood pressure, with the prevalence increasing in older age groups, the impact of this innovation is significant. The NHS Health Check Programme alone diagnoses 38,000 new cases annually in England, indicating that a two percent improvement translates to 750 fewer potential misdiagnoses per year in England and a considerable number globally.

Researchers utilized statistical modeling on arm and ankle blood pressure data from 33,710 individuals worldwide to establish the relationship between arm and ankle blood pressures, predict arm blood pressure using ankle readings, and forecast critical health outcomes such as the risk of heart attacks based on ankle blood pressure readings.

This research has the potential to address health disparities by offering precise and personalized blood pressure measurements for individuals who previously faced challenges in obtaining accurate readings from their arm. In the UK alone, there are approximately 10,000 adults living with upper limb loss, while 75% of the country's 1.3 million stroke survivors experience upper limb dysfunction, making arm blood pressure measurement difficult in some cases.

The study received support from the Stroke Association and Thalidomide Trust. Juliet Bouverie OBE, CEO of the Stroke Association, highlighted the importance of accurate blood pressure readings, especially for stroke survivors who may have difficulties due to paralysis in an arm. Professor Kevin Munro, Director of NIHR's Research for Patient Benefit Programme, commended the research for providing a solution to measure blood pressure in individuals unable to monitor it via the upper arm, emphasizing the significance of blood pressure monitoring in maintaining overall health.

The paper, titled 'Arm Based on LEg blood pressures (ABLE-BP): Can systolic ankle blood pressure measurements predict systolic arm blood pressure? An individual participant data meta-analysis from the INTERPRESS-IPD Collaboration,' is published in BMJ Open.