Only half hour of passive smoking 'damages heart'

Passive smoking for just 30 minutes can damage the heart, according to a study which immediately prompted new calls for more California-style restrictions to stop non-smokers being exposed to fumes.
Japanese doctors said they had evidence that the coronary circulation of healthy non-smokers was affected so badly by short exposure to fumes that parts of their hearts looked no different from that of smokers.

The team from Osaka city university medical school, reporting in the Journal of the American Medical Association, used ultrasound imaging to check chambers, valves and other parts of the hearts of 15 non-smokers and 15 "healthy" smokers, with an average age of 27, before and after exposing them to 30 minutes of passive smoking.

They measured the so-called coronary flow velocity reserve (CFVR), which indicates how well cells that line cavities of the heart and blood vessels perform.

"Our data revealed that temporary passive smoking abruptly reduced CFVR in non-smokers but did not affect CFVR in active smokers. This provides direct evidence of a harmful effect of passive smoking on the coronary circulation in non-smokers."

The authors admitted however that the study did not allow them to assess the long-term effects of passive smoking, or for how long the CFVR was reduced in non-smokers. "These effects may be worth testing in a long term trial."

The American Heart Association has suggested that risk of death from heart disease might be increased by 30% among those exposed to smoke from other people's tobacco at home and by more in those who endure "secondhand" smoke at work.

An editorial accompanying the Japanese study said the findings "add to the evidence that everyone should be protected from even short term exposure to toxins in secondhand smoke".

One of the editorial's authors, Stanton Glantz, of the University of California will tomorrow be the first witness at an inquiry into smoking in public places by the Greater London assembly.

Action on Smoking and Health said: "If something as hazardous as cigarette smoke was leaking from a pipe in a factory, inspectors would close it down, yet there are still 3m non-smokers in Britain that are frequently or continuously exposed to tobacco smoke at work."

The Department of Health said a survey this summer would review how many restuarants, pubs and other licensed premises were following voluntary codes on providing more non-smoking areas.