DUAL bronchodilators have long been used to treat people affected by chronic obstructive pulmonary disease (COPD), as well as patients with a history of smoking presenting with respiratory symptoms that do not fit the criteria for COPD. However, new research shows that these medications do not work for those who are not affected by the disease. It was always assumed dual bronchodilators, which relax the airways and ease breathing, would work for these patients. Often doctors assume a patient has COPD, or that the inhalers will improve smoking-related symptoms.
Principal investigator MeiLan K. Han, University of Michigan, Ann Arbor, USA, and her team conducted a 12-week, randomised, double-blind study, enrolling 535 adults with COPD symptoms. They used inhalers containing either a placebo or medication twice daily. The participants were assessed using the St. George’s Respiratory Questionnaire at the end of the trial. Some of the adults showed improvements; however, there was no significant difference between those who had received the placebo, and those who received medication (improvement in 59% of the placebo group versus 56% of the medication group).
The study showed that only patients with significant lung damage, which results in abnormal spirometry readings, benefit from bronchodilator therapy. First of all, this highlights that it is important to correctly diagnose lung conditions through spirometry, which Han stated is underutilised. At this time, spirometry readings are only used in approximately one third of COPD-related medical visits, and half of the patients who meet COPD criteria are not diagnosed. Second, these result highlight the importance of developing new therapies for these patients.
Han went on to say that we cannot continue to treat patients the way we have, and expect to see improvement. Any patient who shows signs of COPD, or has a history of smoking, should be tested using spirometry. Furthermore, future research should focus on developing targeted therapies for these patients. The researchers believe that treatments targeting mucus production in the airways may be effective for them; however, further studies should help identify treatments.
