Asthma: passive smoking increases the severity

Passive smoking appears to increase the severity of asthmatic disease and may even influence the risk of hospitalization, report U.S. scientists in the journal "Thorax".

To the extent that people with asthma have chronic airway inflammation, they are likely to have exacerbations after being found guilty of passive smoking, remind Dr. Mark Eisner of the University of California, San Francisco and its U.S. and Canadian colleagues.

So far, few studies have examined the link between adult asthma and passive smoking. In addition, most epidemiological studies already published on the subject have only relied on the statements of the participants' exposure to cigarette smoke.

To avoid this bias and more accurately assess the acute exposure of participants to passive smoking, the researchers of the team led a study of non-smoking adults with asthma.

They first assessed the impact of recent exposure to cigarette smoke. For this, 189 people had to wear seven days a "nicotine badge" means a device designed to trap ambient nicotine in a filter, whose contents can then be identified and analyzed by gas chromatography.

In addition, radio-immunoassays were performed to measure the concentration of nicotine and its major metabolite (cotinine) in hair samples from 138 participants in order to assess their level of exposure to cigarette smoke in During the previous three months.

These analyzes allowed the authors to identify a situation of passive smoking for most participants (between 60% and 83%, depending on when the analysis was carried out and the methodology used).

By comparing the data on the level of recent exposure to cigarette smoke obtained through "badges nicotine" and patient testimonials on the severity of their asthma collected during telephone interviews, the authors found that smoking most important recent liabilities associated with greater severity of illness, regardless of demographics and smoking history.

In addition, participants in which significant levels of nicotine exposure during the previous quarter were highlighted presented a prospective increased risk of hospitalization for asthma, the authors note.

This study highlights the existence of a link between passive smoking and poor asthma control, which, in terms of public health advocates banning smoking in public places, they conclude.

In France, Yves Bur UMP (Bas-Rhin) to the National Assembly a bill to ban smoking in all public places.