As many as half of the children and siblings of people with coronary artery disease may also have signs of atherosclerosis (or hardening of the arteries) even without any symptoms, according to a new study published in the AHA journal Circulation. Researchers from the University of Texas reported that family history is a more important risk factor than had been thought.

The good news, according to these researchers, is that doctors can find heart and blood vessel disease early in these individuals, before it has caused any clinical signs such as a heart attack, stroke or chest pain, and treat them aggressively. They can do this with a non-invasive imaging method called positron emission tomography, or PET, which images the blood flowing inside the heart to indicate how well the coronary arteries are working. PET is still an investigational technique; more studies need to be performed to clarify its potential role in detecting coronary disease.

Treatment or prevention in these people would include dietary measures to keep body weight under control, increasing exercise, and prescribing cholesterol-lowering drugs even for people with normal cholesterol levels, according to the lead researcher. He cited other studies which have shown that lowering cholesterol to lower-than-normal levels may prevent the development of coronary artery disease and heart attack even in these high-risk individuals.