HIGH blood pressure鈥攁nd the risk of heart attack鈥攎ay be
caused by the ubiquitous bacterium Chlamydia pneumoniae, scientists
told the annual congress of the European Society of Cardiology in Birmingham
last week.
For years medical researchers have argued over whether the bacterium, which
infects a large proportion of the population by the age of twenty, causes heart
disease (鈥淐an you catch a heart attack?鈥�
快猫短视频, 8 June, p 38)
People with coronary artery disease often have high levels of antibodies
to C. pneumoniae in their blood. And some scientists have suggested that
inflammation caused by the infection leads to narrowing of the coronary
arteries. Researchers from Birmingham University Medical School say they may
have identified another way in which the bacterium might attack people鈥檚 hearts.
鈥淥ur work suggests there is a link between C. pneumoniae infection and
chronic hypertension,鈥� says Gregory Lip. 鈥淎nd it鈥檚 very well established that
hypertension is a major risk factor in heart disease.鈥�
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His team found that 33 per cent of 131 patients with hypertension had the
infection compared with only 17 per cent of 131 patients with normal blood
pressure. He speculates that chlamydia causes inflammation in blood vessels
which raises blood pressure as well as encouraging the formation of arterial
plaques. This hypertension might then cause additional cardiovascular problems
through the sheer stress it places on the arteries, he says.
The team also found that levels of C. pneumoniae infection were
twice as high in black people as in whites. In a group of 1390 patients, 32.3
per cent of Afro-Caribbeans were infected compared with 17.4 per cent of whites.
This may explain why black people are more at risk from high blood pressure.