不良研究所

Not everything new is better than the old, according to a researcher at the Research Institute of the 不良研究所 Health Centre (MUHC). Her study recently published in the British Medical Journal, shows that the traditional drugs used to treat asthma, known as corticosteroids, still work better than the newer ones.

"Inhaled corticosteroids have been the cornerstone of asthma management because of their efficacy, tolerance and rapid action compared with other drugs," says Dr. Francine Ducharme, epidemiologist and pediatrician at the Montreal Children's Hospital of the MUHC. "This study suggests that corticosteroids should remain the gold standard of asthma treatment."

Asthma, a chronic lung disease that affects approximately three million Canadians of all ages, is characterized by disrupted breathing, periodic attacks, and may be fatal. Although there is no cure, with proper management and drug intervention the overwhelming majority of asthmatics can lead a normal and active life.

Data from 13 clinical trials, involving children and adults with asthma, was analyzed. The frequency of asthma attacks was compared between patients who received the standard corticosteroid treatment and those who were given corticosteroids in combination with the newer drugs, anti-leukotrienes. The addition of the anti-leukotrienes to the corticosteroid preparation did not significantly decrease the number of asthma attacks in comparison with corticosteroids alone but it may modestly improve asthma symptoms. There is not sufficient data to tell whether adding anti-leukotrienes to corticosteroids is any better than increasing the dose of corticosteroids. "The data also indicate that the anti-leukotrienes in combination with corticosteroids do not permit a significant reduction in the dose of inhaled corticosteroids; however there is some indication that asthma control may be slightly better with the combination therapy. Anti-leukotrienes at usual doses are safe but use of the anti-leukotrienes above their recommended dosage may have serious adverse side affects," says Ducharme.

"Physicians are interested in using these anti-leukotrienes because they are new to the market and some clinical trials have shown positive results. A thorough analysis of the data from all clinical trials, however indicates that, until further evidence is available, we should not switch our asthma control strategy, " she says.

Of the 376 clinical trials reviewed by Ducharme for this study, only 13 met her rigorous criteria of study design, patient selection and treatment comparison. " Drug treatment can make a huge difference in the quality of life of asthma patients but we need to be absolutely sure that we are providing the best possible therapy. Before we change our practice guidelines it is important to critically evaluate all the data; in this case, we definitively need more relevant trials to better assess the place of anti-leukotrienes in asthma therapy," she said.