Blood pressure at night is higher than previously thought

Scientists at UCL have developed new technology which reveals that blood pressure measured close to the heart is much higher during sleep than previously thought. Night time blood pressure is a strong predictor of both heart disease and stroke, with previous studies establishing that blood pressure measured over the arm falls at night during sleep. However these new data indicate that the night-time decline in blood pressure may be less extensive than previously thought. The research, published in the June edition of the journal Hypertension, could have significant implications for the evaluation of future therapies as drugs used to treat high blood pressure can have markedly different effects on pressure close to the heart, compared to that traditionally measured in the arm. The team, led by Professor Bryan Williams at UCL's Institute of Cardiovascular Science, and supported by the National Institute for Health Research (NIHR), worked with a Singaporean technology company (Healthstats International). They developed a portable wrist watch-based device containing a sensor in the strap which detects the pulse wave at the wrist, rather than measuring the pressure directly. By mathematically modelling the pulse wave, the team was able to accurately measure pressure at the aortic root (i.e.