After rising for more than a decade, the rates of awareness and control of high blood pressure -- a major risk factor for stroke and heart disease -- appear to be falling. Furthermore, the general public and the nation's physicians need a "wake up call" to reduce this potential danger, according to a report in Hypertension: Journal of the American Heart Association.
"We are seeing a definite leveling-off, even a deterioration, in our level of awareness, treatment and control of hypertension, possibly because we aren't paying enough attention to it," says Irene Meissner, M.D., a neurologist who is leading a study at the Mayo Clinic's department of neurology to examine risk factors for stroke and heart disease in the community.
When Meissner and other researchers interviewed 636 adults from the Olmstead, Minnesota, community and measured their blood pressure they found that 53 percent had high blood pressure (defined as a consistent reading of 140/90 mm Hg or higher). Of great concern, two out of five (39 percent) of these subjects were unaware of their condition, and less than one out of five (17 percent) was receiving treatment to control it.
Participants in the Mayo Clinic study were age 45 or older. They had blood pressure readings taken both at home and at the doctor's office. In each instance, several readings were taken and then averaged. Participants were asked to refrain from smoking (which can raise blood pressure) both before and during the blood pressure measurements.
From the mid-1970s to the early 1990s, there was progressive improvement in the rates of awareness, treatment and control of high blood pressure, according to national surveys. During this period, the percentage of patients who were aware of their high blood pressure rose from 31 percent to 55 percent. The number of patients whose blood pressure maintained a controlled reading of 140/90 mm Hg or below increased almost three-fold, from 10 percent to 29 percent.
However, the trends changed in the early 1990s, according to the 1993 nationwide study by the Joint National Committee on Prevention, Evaluation and Treatment of High Blood Pressure. This study reveals small, but significant, declines in these percentages.
"This [national data] also suggests that instead of making progress in combating the health threat posed by high blood pressure, we may actually be backsliding," Meissner says. "People aren't as aware as they should be and control rates are quite low. This is happening despite solid clinical evidence that proper detection and treatment can dramatically reduce the number of deaths and disabilities caused by uncontrolled high blood pressure.
"Our results from the Olmsted County study show a low rate of high blood pressure awareness and control that is disturbing, particularly because the study participants lived in an economically prosperous area with easy access to health care-- so there were no apparent financial barriers or lack of healthcare resources that might explain the study's findings."
Results of this study help to further substantiate previous nationwide studies, which also suggested a decline in awareness, treatment and control of high blood pressure. Together, these findings raise several crucial questions, according to Meissner, such as: Are other health issues "crowding out" concern about high blood pressure? Is complacency on the part of healthcare providers and the public a factor? Is the cost of high blood pressure therapies an important factor in these findings? And finally, what is the effect of managed care?
"The answers to these questions are not readily apparent from our study," Meissner says. "But this is an important subject for future research. Understanding the cause or causes is a necessary first step toward reversing these unfavorable-- and potentially dangerous-- trends."
Co-authors were Jack P. Whisnant, M.D.; Sheldon G. Sheps, M.D.; Gary L. Schwartz, M.D.; W. Michael O'Fallon, Ph.D.; Jody L. Covalt, JoRean D. Sicks, Kent R. Bailey, Ph.D. and David O. Wiebers, M.D.
Media advisory: Dr. Meissner can be reached by calling Mayo Clinic Communications at 507-284-2387. (Please do not publish phone number.)