Aortic dissection usually occurs in older people with high blood pressure and cocaine is not a widely recognised risk factor for the problem, they say.

However, the researchers from the University of California and San Francisco General Hospital say that in urban hospitals serving uninsured patients acute aortic dissection is commonly associated with a history of cocaine use.

The drug causes an increase in stress hormones that can cause blood pressure to rise rapidly. This may tear the lining of the vessel allowing blood to enter and rip it even further, says Dr Priscilla Hsue, primary researcher. The dissection may stop blood from reaching critical organs or even cause the aorta to rupture, she points out.

The study looked at 38 cases of aortic dissection between 1981 and 2001. The researchers found that 37 per cent of cases occurred in cocaine users, who were all smokers, tended to be African-American and had an average age of 41, compared to 59 years in non-users of the drug.

Hypertension had been diagnosed in 79 per cent of the cocaine users, 71 per cent had documented left thickening of the heart wall and at least 64 per cent were not taking their prescribed anti-hypertensive medication.

Twenty-nine per cent of the drug users died in the hospital, nearly twice the rate of the non-cocaine users.

“In urban settings, aortic dissection should be considered when young people come to the emergency room with severe chest pain, especially if they have other risk factors like high blood pressure and smoking,” says Dr Hsue.

Source: Circulation - Journal of the American Heart Association, March 2002