Many people with high blood pressure are only diagnosed when they go to their doctor about other unrelated symptoms, a new survey indicates.

High blood pressure (hypertension) can cause silent damage to the blood vessels and heart, as there are few symptoms and the only way you can find out you have it is by having it measured. If left untreated, the damage progresses over time and can cause a range of problems, including atherosclerosis (hardening of the arteries), stroke and heart failure.

According to the survey of over 1,000 Irish adults, 48% of those with high blood pressure were only diagnosed when they sought help for other health problems.

While almost eight in 10 of those surveyed said they had their blood pressure checked in the past year, less than one in three knew their reading.

Blood pressure is recorded as two numbers, such as 120/80. Systolic is the higher number and it refers to the pressure in the arteries when the heart beats. Diastolic is the smaller number and it refers to the pressure in the arteries between heart beats.

According to of the Irish Heart Foundation's (IHF) medical director, Dr Angie Brown, the findings suggest that GPs ‘are to be congratulated on detecting hypertension when patients present with other ailments and symptoms'.

"Given the often silent nature of hypertension with little or no symptoms, this type of opportunistic screening of the public is vital to identifying people with the condition.

"It is the lack of symptoms that is driving the public awareness campaign to encourage more adults to get checked for hypertension, to know their blood pressure reading and to understand the importance of keeping it at a healthy level through a combination of lifestyle change and medication where necessary," she commented.

Also commenting on the survey findings, Dr Eamon Dolan, a consultant geriatrician at Connolly Hospital in Dublin insisted that blood pressure control is a ‘key issue in Ireland today'.

"In 2007, nearly 852,000 adults in Ireland had high blood pressure. By 2020, this is expected to rise to over 1,192,000. What is most concerning about this statistic as a medical professional is that many people included in this cohort do not realise they have raised blood pressure and that it may be doing them harm," he said.

The IHF added that a normal level of blood pressure is 120/80. Anything above 140-90 requires medical attention. The survey was carried out to coincide with World Hypertension Day (May 17).