Blood pressure difference between arms linked to early death

Doctors should test both arms, say researchers

A large difference in blood pressure between the left and right arm can indicate a greater risk of dying early, researchers have said. A study of 230 patients with high blood pressure living in rural Devon found that those with a large difference in blood pressure readings were more likely to die within ten years from heart disease, stroke or other cardiovascular conditions.

Blood pressure measurement is recorded as two numbers, systolic and diastolic. The systolic reading is a measurement of the pressure in the blood vessels when the heart contracts, while the diastolic one is the pressure in the blood vessels when the heart relaxes between beats. Every one mmHg difference in systolic blood pressure between the right and left arm increased the risk of dying by six per cent, the study found.

A one mmHg difference in diastolic blood pressure between arms was found to increase the risk of death by nine per cent. The study findings prompted the researchers to suggest that blood pressure should be routinely measured in both arms in all patients with high blood pressure. Although national guidelines advise doctors to measure blood pressure in both arms, this often does not happen, the researchers said.

Dr Christopher Clarke, who led the study, said: "This study supports the potential value of an inter-arm difference as a simple indicator of increased cardiovascular risk. "Assessment of blood pressure in both arms is recommended by guidelines and should become a core component of initial blood pressure measurement in primary care."

Maureen Talbot, senior cardiac nurse at the British Heart Foundation, said: "This study supports national guidelines, which recommend that blood pressure readings are taken in both arms. "It is normal to have a small difference in your blood pressure readings between arms. However, a big difference between your readings may carry risks, so more tests could be needed to check your heart health. If you want to find out your blood pressure, visit your GP or practice nurse to have it measured."

The study was published in the British Medical Journal.

The Family GP