People who regularly fail to get enough sleep appear to have an increased risk of developing high blood pressure, a new study suggests.

High blood pressure, also known as hypertension, is a major cause of heart attack and stroke. However, it rarely carries any signs or symptoms. In fact, a person can look and feel well even if they have it. The only way to know if you have it is to have your blood pressure checked by a health professional, such as a GP or pharmacist.

US researchers set out to investigate the impact of shortened sleep on blood pressure. Eight healthy adults aged between 19 and 36 took part in a 16-day inpatient experiment. They spent four nights sleeping normally, followed by nine night of either normal sleep (nine hours per night) or restricted sleep (four hours per night).

This was followed by three days of recovery. Their blood pressure was monitored throughout.

The study found that those whose sleep was restricted had much higher blood pressure measurements - 115/64 compared to 105/57mmHg (millimeters of mercury).

Furthermore, while blood pressure usually falls during the night, the researchers found that this expected fall was suppressed in the participants who were not getting enough sleep.

The heart rate of those with restricted sleep was also higher than the rate of those with normal sleep.

The researchers from the Mayo Clinic emphasised that high blood pressure, ‘particularly during the night, is one of the major risk factors for heart disease'.

"For the first time, we demonstrated that insufficient sleep causes increases in nighttime blood pressure and dampens nocturnal blood pressure dipping by using a controlled study that mimics the sleep loss experienced by many people," they explained.

Details of these findings were presented at the American College of Cardiology's 64th Annual Scientific Session in San Diego.