Patients with clinical features of both asthma and COPD should be generally be treated with both inhaled corticosteroids and bronchodilators even though there is sparse evidence to guide optimal therapy and continuing debate about the validity of the ‘asthma-COPD overlap syndrome’ (ACOS), according to a recent review.
The review, in Lancet Respiratory Medicine, was co-authored by Associate Professor Helen Reddel from the University of Sydney, who is chair of the Global Initiative for Asthma (GINA) Science Committee.
Professor Reddel told the limbic that ACOS is a ‘hot topic’, evidenced by an increasing number of review articles, but there is a continuing scarcity of reliable data.
“Much of the current evidence is from highly selected populations and is not necessarily generalisable to patients seen in clinical practice,” she says.
“It’s likely to take several years before firm evidence-based treatment recommendations can be made. In the meantime, recommendations are largely based on safety considerations.”
The review highlights the joint GINA-GOLD guidelines on ACOS recommending that initial treatment “default towards treating for severe asthma”, specifically avoiding monotherapy with a long-acting bronchodilator.
In clinical practice, Professor Reddel says that if patients with long-standing asthma eventually develop irreversible airflow limitation, it is vital that a current diagnosis of asthma stays in their health record and they continue to be treated with ICS.
Deaths have been identified in patients in whom the diagnosis was changed from asthma to COPD and ICS ceased.
The review stresses that ACOS is not a disease entity, but simply a term applied to patients with clinical features of both conditions.
“Some commentators have attacked the concept of ACOS, but this problem appears to have largely arisen from different usage of the word ‘syndrome’,” Professor Reddel says.
“We consider a syndrome to represent a cluster of similar clinical features, but others consider it to represent clinical features due to the same underlying disease process.”
Current Australian guidelines tend to support the concept of asthma and COPD as two single diseases that may occur in the same patient, but both asthma and COPD are in fact heterogeneous conditions, sometimes with the same underlying mechanisms.
“Ageing is a further contributor,” she says. “As patients with asthma grow older, their clinical features tend to resemble many of those of COPD.”
For patients with features consistent with both asthma and COPD, referral to a specialist is recommended, as these patients have more difficult clinical problems and worse outcomes than those with either asthma or COPD alone.
“If in doubt, treat with ICS/LABA while awaiting referral for confirmation of the diagnosis,” she says.
ACOS creates the potential for confusion with the multiple new respiratory medications being launched.
In addition to ICS and bronchodilator therapy, guided by the separate treatment recommendations for each disease, problem-based management is helpful in patients who have features of both asthma and COPD, Professor Reddel says.
This includes exercise training or pulmonary rehabilitation to avoid the vicious cycle of deconditioning and obesity that occurs once patients have shortness of breath on exertion.