The number of infections a person has been exposed to is linked to artery thickening and risk of death from heart attack.

It's long been suspected that infection plays a role in the development of heart disease, perhaps by promoting inflammation within the coronary arteries. However, the studies that have been done have produced, so far, conflicting evidence. Now researchers at Harvard Medical School have shown a direct association with the number of infections and artery thickening and heart attack death.

The tested 572 patients admitted to hospital with chest pain or heart attack for eight different infective organisms. Four were viruses - two types of herpes, cytomegalovirus (a serious problem in those with compromised immunity) and Epstein-Barr virus. The four bacteria tested for were: Haemophilus influenzae , Chlamydia pneumoniae and Mycoplasma pneumoniae - which cause flu and pneumonia - plus the stomach bug Helicobacter pylori .

The more infections a person had been exposed to, the greater the extent of artery thickening in the heart, neck and legs. On follow up over the next three years or so, there was a link between the number of infections and the likelihood of heart attack death. Those who had up to three infections had a 3.1 per cent chance of dying, those with four to five had a 9.8 per cent chance, and in those with six to eight infections, the chance went up to 15 per cent. The figures were higher still in those with more advanced atherosclerosis.

The study does not show that infection causes heart disease. These patients already had suspected heart trouble and maybe the infection came after? But it shows that the infection and heart disease link is worthy of further investigation.

Source

Circulation January 8 2002