FRIDAY, Jan. 28, 2005 (HealthDayNews) -- Here's one more study that shows smoking is bad not only for the health of people who light up but also for those around them -- specifically, for children who breathe in their parents' secondhand smoke.
This research comes from Europe, and it finds that children exposed to secondhand smoke on a daily basis have more than triple the risk of lung cancer and an increased risk of other respiratory problems later in life than those who grew up in a smoke-free environment.
The report appears in the Jan. 28 online issue of the British Medical Journal.
While a number of previous studies have shown the same sort of risk, this one is different because "it is one of the few prospective studies in which information about exposure has been collected before information about the outcome," said study author Dr. Paolo Vineis, a professor of environmental epidemiology at Imperial College London.
It also included a large number of people, more than 123,000 in 10 European countries, who provided information on exposure to secondhand smoke and were followed for an average of seven years.
During that time, 97 people in the study had newly diagnosed lung cancer, 20 had cancers of the upper respiratory tract and 14 died of chronic obstructive lung disease or emphysema.
The increased lung cancer risk was the most striking -- 3.6 times greater for those whose parents smoked. That might seem a large number but, Vineis said, "most of these people are nonsmokers, and you have to put together a lot of people to detect a relatively small number of lung cancers."
Overall, the risk of all lung diseases was 30 percent higher for those exposed to secondhand smoke in childhood, the study found. Predictably, the risk was "consistently higher in former smokers than in those who never smoked," the report said.
The finding adds to the damage that secondhand smoke is known to inflict on children. The U.S. Environmental Protection Agency estimates that secondhand smoke is responsible for 15,000 to 300,000 lower respiratory tract infections in children each year, causing 7,500 to 15,000 hospitalizations. The EPA also blames secondhand smoke for as many as 1 million asthma attacks in children annually.
And secondhand smoke can be more immediately fatal to children. It is blamed for an estimated 1,900 to 2,700 cases of sudden infant death syndrome in the United States each year.
"Most countries are introducing laws about secondhand smoke exposure," Vineis said. Most recently, Italy has banned smoking in all public places, including bars and restaurants. New York and other cities in the United States have similar bans.
Smoking at home cannot be banned. But "parents should avoid smoking at all times in the presence of their children," Vineis advised.
Dr. Norman Edelman, a consultant on scientific affairs for the American Lung Association, goes further. "If you must smoke, don't smoke in an indoor area that is shared by anyone else," he said.
One important finding of the new study is that the harmful effect of secondhand smoke is much greater in former smokers than nonsmokers, Edelman said.
"It gives credence to the idea that total exposure to smoke is a major determinant of damage," he said. "Basically, cigarette smoke is bad no matter how you take it in."
The dangers of secondhand smoke are described by the U.S. Environmental Protection Agency.