In brief

Bad actor in cardiovascular disease may play role in fractures

Most people who’ve heard of homocysteine associate it with heart disease. Homocysteine is an amino acid produced by the breakdown of various proteins in the body. Levels tend to increase with age, and in excess, it can damage blood vessels, causing plaque to build up in the artery walls. About half of all people with cardiovascular disease have too much homocysteine in their blood. It appears that elevated homocysteine may also increase fracture risk, at least in people over age 55. This finding could open the way to a fuller understanding of age-related osteoporosis and additional options for preventing it.

It has been known for a long time that very high blood levels of homocysteine are related to osteoporosis in people with a rare genetic disorder called homocystinuria. In two separate studies, scientists in Boston and in the Netherlands have examined the relationship between moderately high blood levels of homocysteine and fracture risk. In the Boston study, researchers analyzed blood samples taken more than 20 years ago from nearly 2,000 men and women participating in the Framingham Heart Study, along with records of hip fractures in the group since 1983.