Practicing slow breathing with the aid of a regulatory device can reduce blood pressure levels in hypertensive patients. The device, called 'Resperate', is the size of a paperback book, and is hooked up to an elastic belt around the chest. The unit monitors the breathing rate of the wearer, calculates the preferred rate and synthesizes a personalised melody comprising of two distinct tones, one for inhalation and the other for exhalation, which is played through headphones. Previous studies using the device have shown its effectiveness in reducing blood pressure, but how long will it have to be used in order to have an effect has not been determined. Researchers from the Rush University Medical Center in Chicago, USA, studied 149 people with high blood pressure to investigate whether there was a minimum duration of slow, device-guided breathing to obtain a significant lowering of blood pressure. They were randomly assigned to use of the device or simply monitor their blood pressure at home. Participants who used the device for at least 180 minutes over the 8-week study (approximately 23 minutes per week) experienced an average drop of 15 points in the higher (i.e., systolic) blood pressure reading as compared with a 7-point drop among those who used the device less than 180 minutes during the study, and a decrease of 9 points for those who just monitored their blood pressure. Even among high users, the device was used only about half the recommended time of 45 minutes/week. The findings suggest that isolated systolic hypertension, can be significantly improved by device-guided slow breathing.
Journal of Clinical Hypertension,
October 2004