National Health and Nutrition Examination Survey (Nhanes)

Accurate measurement of blood pressure (BP) is a major public health concern; it is essential for hypertension screening, as well as for disease management. In the period of 2005-2006, 29 percent of the U.S. adult population was hypertensive or taking medication for hypertension. Blood pressure has been measured with the mercury sphygmomanometer for many years but with new technologies available, alternative blood pressure devices have taken center stage. The rapid pace of the development of automated sphygmomanometers with improving accuracy and reliability combined with increasing affordability has meant that these devices have now replaced the mercury sphygmomanometer in many settings. During the 2007-2008 NHANES cycle, a blood pressure methodology study was successfully completed in order to develop a preliminary understanding of alternative blood pressure devices - namely the OMRON HEM-907 XL. The purpose of the study was to validate the OMRON HEM-907 XL by assessing its accuracy according to industry standards using a convenient sample. Initial findings indicate the OMRON machine passed both the American and British protocols. Because of systematic measurement differences between blood pressure devices, comparison of blood pressure values between different populations or within populations over time is hampered when different blood pressure devices have been used.1 Therefore, one pertinent question still needs to be addressed - how will the national estimate of hypertension prevalence be affected if an automated machine is used to replace the mercury sphygmomanometer? NHANES must be able to compare the measurements taken by the mercury device to those taken by a possible successor device in such a way that trends over time in blood pressure prevalence can be accurately maintained and followed. Furthermore, these results would help to better compare blood pressure values in research studies that used different blood pressure devices.