High blood pressure is usually associated with poor prognoses in heart disease. But that means blood pressure monitored at rest. The new findings show that it is important to factor in the situation in which the blood pressure is measured.
The study, by researchers Ulf Stenestrand, Fredrik Nyström, Magnus Wijkman, and Mats Fredriksson of Linköping University, comprised 119,151 patients admitted to intensive heart care for acute chest pain between 1997 and 2007. The data was retrieved from RIKS-HIA, a register that covers all Swedish intensive heart care units.
The blood pressure first measured upon admission was related to the risk of the patient dying during the care period or within a year. It turned out that the higher the upper, systolic, pressure was, the lower was the risk of dying. Among patients who had more than 162 mm Hg, the fatality risk was 22 percent lower than for those in the interval 128-144. The latter in turn ran a 40-percent lower risk of dying than those whose systolic blood pressure was under 128 mm Hg.
"The really big news in the study is that the risk continued to decline at even higher levels, all the way up to 200 mm Hg, after which the reduction in risk leveled off," says Fredrik Nyström, professor of internal medicine.
The differences between the various groups were even clearer when the researchers examined the patients‘ risk of dying only from cardiovascular disease. The improved prognosis was also valid for high-risk groups, such as diabetics, smokers, and obese patients.
It was previously known that low blood pressure can be associated with poor prognoses for certain types of heart disease, but in those cases the low blood pressure was caused by heart failure.
RIKS-HIA, the Swedish registry of intensive heart care, was created in 1991 by Ulf Stenestrand and Lars Wallentin, now professor of cardiology at Uppsala University. Now all 74 hospitals that receive heart patients in Sweden are now covered, as are those in Iceland and on the Finnish island of Åland in the Baltic. Ulf Stenestrand, who was an associate professor at Linköping University and chief physician at the heart clinic at Linköping University Hospital, died in February, only 49 years old.
"Association between admission supine systolic blood pressure and 1-year mortality in patients admitted to the intensive care unit for acute chest pain" by Ulf Stenestrand, Magnus Wijkman, Mats Fredriksson, and Fredrik Nyström. Journal of the American Medical Association (JAMA) March 24, 2010.
Professor Fredrik Nyström, Department of Medicine and Health, phone: +46 (0)13-227749, firstname.lastname@example.org
Pressofficer Åke Hjelm, email@example.com; +46-13 281 395