Under Acute Stress, Higher Blood Pressure May Not Be Such a Bad Thing

Though low blood pressure is usually considered something to aim for, new research suggests that under times of acute stress, the heart may actually benefit from higher−than−recommended blood pressure. The study comes from researchers at Linköping University in Sweden.

Some researchers believe that it may indicate that these patients actually have better cardiovascular reserves, and are therefore able to deal more effectively with acute heart problems.

The researchers studied over 119,000 participants over a period of ten years. All participants had suffered from chest pain at some point during the study and were treated for it in an Intensive Care Unit. The research team, led by Ulf Stenestrand, divided the participants into quartiles, based on their systolic blood pressure (this measure is the “top” number in a blood pressure reading, and represents the pressure in the heart when it is contracting during a beat). They looked at systolic pressure as it related to the patients’ mortality risk one year after the initial episode of chest pain.

The results showed that patients with the lowest systolic blood pressure (under 128 mm HG) actually had the worst prognosis: compared to people whose pressures ranged from 128−144 mm Hg, the death risk of those with the lowest systolic pressures was 40.3% greater. Fitting with this trend was the fact that those with the highest systolic pressures (over 163 mm Hg) had the best prognosis: their risk of dying was 21.7% lower than those in the second lowest group.

Since high blood pressure has typically been associated with worse long−term prognosis, how is it that this study found a link to better short−term outcome and lower risk of death? Some researchers believe that it may indicate that these patients actually have better cardiovascular reserves, and are therefore able to deal more effectively with acute heart problems. However, the authors of the study do caution that their results should not be regarded as a “suggestion not to normalize an elevated BP in patients with acute chest pain.” Doctors should still encourage their patients to keep blood pressure at what has been established as a healthy reading (typically 120/80 mm Hg).