The Salmeterol Multicenter Asthma Research Trial (SMART) has been published by Chest. This study led to additional warnings being added to Long-Acting Beta-2 Agonists (LABAs) in America, as reported here. The study is available online as abstract and PDF.
The full publication of the study may raise awareness of these warnings again. There are some key points from the study that can assist in allaying patients' fears.
This study was:
- expected to run for 12 years, recruit 60,000 patients and examine 238 primary outcomes. In fact it ran for 8 years, recruited 26,355 patients and identified 97 primary endpoints.
- designed in the early 1990s and did not demand that patients were also on inhaled corticosteroids (ICS). Use of ICS is now accepted as good practice and is Step 2 of the British Thoracic Society Guidelines.
- not statistically significant for the primary outcome and the warnings are based on a secondary outcome. This may not be a statistically valid process.
Despite all of these potential confounders clinicians should be aware that the study might have identified a trend to harm. The MHRA issued advice to inform clinicians as follows:
The MHRA remind prescribers that:
- patients given salmeterol or formoterol should always be prescribed an inhaled corticosteroid
- patients with acutely deteriorating asthma should not be initiated on salmeterol or formoterol
- patients should be monitored closely during the first 3 months of treatment
Action: Clinicians involved in the treatment of asthma should ensure that the MHRA advice is being followed.