Patients may not respond well to lung medications if they are exposed to cigarette smoke and a type of flu virus, a new study found.
Cigarette smoking is the leading cause of chronic obstructive pulmonary disease (COPD). It may also disrupt the efficacy of the most common symptom-relieving lung drugs called β2-adrenoceptor agonists. Aside from cigarette smoking, infection with the influenza virus may prevent the drugs from working properly.
In a new study published online in the journal Clinical Science, researchers from the Royal Melbourne Institute of Technology (RMIT) in Melbourne, Australia found that the effectiveness of the most commonly used drug, salbutamol, to relieve specific symptoms of lung disease, could be reduced when the patient is exposed to influenza A infection and cigarette smoke.
COPD is a term used to refer to several lung diseases that cause blockage of airflow in the lungs, which results in shortness of breath and other breathing-related problems. Included in this collective disease term are emphysema, chronic bronchitis, and asthma.
One of the most important drugs used to relieve the symptoms of COPD is salbumatol, which is a β2-adrenoceptor agonist. It works as a bronchodilator, a drug used to dilate the airways to make it is easier for patients to breathe.
"By understanding the mechanisms responsible for reduced sensitivity to current bronchodilators, we can then design alternative, more efficacious agents to help treat people with COPD, especially during a viral exacerbation," Dr. Chantal Donovan from Monash University, said.
The team assessed the effects of salbutamol on the lungs of mice exposed to the virus and cigarette smoke. The results revealed that the lung tissue that has been exposed to these factors was less responsive to the effects of the drug.
If the influenza virus and cigarette smoke reduced the drug's efficacy, new treatment methods should be developed, according to researchers.
"There is a clear need for new therapies that can overcome the limitations of current drugs used to treat COPD and associated flare-ups. When combined with knowledge gained through clinical research, animal models utilizing cigarette smoke exposure are a valuable tool in the quest to identify new therapies for this life-changing condition," Dr. Ross Vlahos, lead author of the study and an associate professor at RMIT University, said in a statement.
Photo: Shannon Holman | Flickr
