What's too low when it comes to diastolic BP?

Patients with low diastolic blood pressure and a high pulse pressure may be at increased risk of coronary heart disease (CHD), a large observational study shows.

The US research reports that a low diastolic BP of between 60 and 69mmHg raises the risk of CHD by 23%, compared with a diastolic BP of between 80 and 89mmHg.

This association was strongest in those people with a systolic BP 120mmHg or more, say the authors from the Johns Hopkins Bloomberg School of Public Health.

The study, which followed individuals with no existing heart disease for 21 years, found that having a pulse pressure