Doctors are warning high blood pressure has become a key concern for Wirral.

They say as many as 45,000 people in the borough may not know they are at risk and are urging residents to have their pressure tested.

Medics say that if unchecked, "the first symptom may be a heart attack or stroke."

Data from Public Health England revealed blood pressure readings from patients of all age groups, taken across 55 Wirral GP surgeries, show nearly 50% were higher than the national average.

Hypertension can lead to long-term conditions such as heart disease and strokes.

Dr Sue Wells, GP and medical director for Wirral Clinical Commissioning Group, said: “The key risk factors for ill health within Wirral include smoking, raised blood pressure, being overweight and lack of exercise.

“In more than 90% of cases, the cause of hypertension is unknown but several factors can increase your risk of developing the condition.

“Untreated high blood pressure can lead to serious diseases, including stroke, heart disease, kidney problems and dementia.”

A campaign called "Change4Life" designed to encourage healthier lifestyles, relaunches this month and could help combat lifestyle choices that can lead to high blood pressure.

Dr Wells added: “It is a welcome opportunity for anyone to kick-start looking after their health but for those with medical conditions, it is always best to discuss any changes to your diet or exercise regime with your GP.

“Remember though as the name ‘Change4Life’ tells us, this is about lifelong changes to help your future and not just a couple of weeks in January.

“The best advice for anyone is to take small steps until you reach your goals."

Dr Pete Naylor, a GP and chairman of the commissioning group, said: “The key consideration here is that it is very rare to get any actual symptoms from high blood pressure, so if people are waiting for these before getting a check they are making a mistake.

“It is a myth that it usually causes headaches, flushing or a pressure feeling.

“It is usually silent and completely symptomless.

“The first symptom may be a heart attack or stroke."

The only way of knowing if you have high blood pressure is to have it measured and it is advised all adults should do so at least once every five years.

GPs and some pharmacies can check your blood pressure and leave the results with your surgery if help is needed.

To find out how to get your blood pressure tested visit www.nhs.uk/conditions/blood-pressure-(high) or www.nhs.uk/change4life for more information.