High Blood Pressure (IMAGE) Lancaster University Caption The World Health Organisation says hypertension affects about 40 percent of those aged over 25 and is a major risk factor for heart disease, stroke and kidney failure. Credit Lancaster Unviersity Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.