Overuse of reliever inhalers is associated with higher risks of developing and dying from cardiovascular disease, including heart failure, heart attack and ischemic stroke, in asthma and COPD patients, according to a study published today in ERJ Open Research.
These 'reliever' inhalers can help people breathe more easily when their symptoms are particularly bad. However, it is possible to overuse them if the patient's asthma or COPD is not being managed well by 'preventer' treatments.
Professor Lies Lahousse, a lead author of the study from Ghent University, Belgium and Erasmus MC Rotterdam, Netherlands, explains: "Short-acting bronchodilator overuse is common. We know that almost one out of five asthma patients and one out of three COPD patients are overusing these inhalers. In both asthma and COPD, we found that increased use of these inhalers was associated with higher risks of cardiovascular disease and death and the risk continued to rise the more inhalers patients used per year.
"Overuse of short-acting bronchodilator is usually the result of poor disease control, both COPD and uncontrolled asthma are linked to an increased risk of cardiovascular diseases and death."
The study assessed real-world data from primary and secondary care of over 280,000 COPD and asthma patients in Belgium who used either SABA (short-acting beta-agonist), SAMA (short-acting muscarinic antagonist), both, or no short-acting bronchodilators to manage their condition. Researchers took into account differences in age, sex, socio-economic status, smoking history, nursing home residency, disease severity, and other conditions or medications.
Both SABA and SAMA bronchodilators are often used as reliever therapies by asthma and COPD patients. SABA bronchodilators increased the risk of death by 12% and 14% in asthma and COPD patients respectively compared to no use, the risk of death from SAMA bronchodilators increased by 73% and 36% respectively. The researchers also assessed how the number of inhalers used per year affected cardiovascular health. They found that using three or more inhalers per year for either bronchodilator was associated with increased risk of death compared with two or fewer inhalers per year. Patients who did not have any prior history of cardiovascular disease were found to be more vulnerable to cardiovascular problems resulting from inhaler overuse.
Professor Lahousse added: "Overuse of short-acting bronchodilators is an alarm signal which indicates uncontrolled airway inflammation and requires a medical review of treatment. It should prompt patients to have their lungs checked and healthcare providers to check adherence and inhaler technique against treatment guidelines.
"Patients should be informed that short-acting bronchodilators only relax airway muscles briefly. Uncontrolled asthma and COPD are already linked to increased risk of cardiovascular disease and death. When this is combined with overuse of SABA and SAMA bronchodilators – which both cause faster, irregular heart rates as a side effect – these risks become even more pronounced. Over-reliance on this short relief may allow the underlying disease activity progress to go unchecked. Our research should draw clinicians' attention to the fact that overuse is common and may be associated with adverse effects, even in patients without cardiac history."
The team is now planning to investigate whether reliever overuse can be avoided by stricter adherence to maintenance treatment, and whether cardiovascular risk assessment or specific cardiovascular therapies might decrease the risks for patients. They also hope to investigate if short-acting bronchodilator overuse in primary care will trigger healthcare providers to check the lungs and monitor disease management more closely.
Dr Pavol Pobeha from the European Respiratory Society's expert group on monitoring airway diseases, based at the Pavol Jozef Šafárik University, Košice, Slovakia, who was not involved in the research, said: "There are no cures for asthma or COPD. As a result, the primary goal of clinicians and patients is to manage symptoms and prevent the conditions from worsening. Relief from bronchodilators plays a key role in this management, helping patients to take control of their own health and improve their quality of life, but it is important that they do not become reliant on these therapies.
"We need improved monitoring systems that give a warning signal when patients are overusing short-acting bronchodilators, enabling doctors to support their patients with the best treatment and care to manage symptoms. This will help patients and their healthcare providers to maximise the benefits of their medication whilst minimising risks."
