Treatment Options in Asthma and Chronic Obstructive Pulmonary Diseases Overlap Syndrome
phenotypes and to specific pharmacological treatments, which limits the exploration of further potential treatment options.
Options and Strategies Smoking Cessation
The role of smoking cessation in obstructive lung diseases, including asthma and COPD overlap syndrome, cannot be overemphasised. Various studies, including the Lung Health Study, show that smoking cessation alters the natural course of both these diseases by slowing the rate of decline in lung function, improving response to corticosteroids, improving quality of life and reducing mortality (see Figure 2).15
Table 2: Available Therapeutic Options for Asthma, Chronic Obstructive Pulmonary Disease and Overlap Syndrome with Relative Efficacy
Smoking cessation Beta-2 agonists Anticholinergics
Inhaled corticosteroids Leukotriene inhibitors Oxygen
Smoking can contribute to misdiagnosis and can lead physicians to diagnose COPD rather than asthma or overlap syndrome, or to attribute symptoms to smoking rather than to asthma.16
The rates of current smoking in patients with COPD is astonishingly high, at about 30–40 %, and that in patients with asthma it is still high, at 20–30 %, but comparable to that of the general population. In a recent large cohort study from Canada, current smokers with either asthma or COPD were more likely to be women from lower socioeconomic strata. Although it has been demonstrated previously that a combination of behavioural and pharmacological therapy obtained better success rates, the same study showed that people with asthma or COPD receive no more counselling from their physicians about smoking cessation than do the non-smokers,17 which highlights the inadequacy of current smoking-cessation efforts. Traditional agents used for smoking cessation, which include nicotine-replacement therapy, bupropion and varenicline, have all been demonstrated to help smoking cessation. The use of varenicline has been associated with the highest sustained abstinence rate; nevertheless, recent reports suggest that this medication may be associated with an exacerbation of underlying psychiatric disorders and increased suicidal ideation.18
Also, a recent meta-analysis
suggested that its use may be associated with an almost twofold increase in serious cardiovascular side effects.19
These risks should be
considered by clinicians when they prescribe varenicline for older adults with a history of cardiovascular or psychiatric disorders.
Pharmacological Treatment
The available therapeutic options and relative efficacy for asthma, COPD and the overlap syndrome are shown in Table 2.
Bronchodilator Therapy
Bronchodilators produce smooth muscle relaxation, which results in improved airflow obstruction, reduction in symptoms, improved exercise tolerance and decreased frequency and severity of exacerbations. Despite these beneficial effects, bronchodilators do
Studies with head-to-head comparisons of long-acting bronchodilators are scant, but novel data from controlled trials in COPD with the once-daily beta-2 agonist indacaterol indicate a superior bronchodilation and clinical efficacy of indacaterol at recommended doses over twice-daily LABA, and at least equipotent bronchodilation compared with once-daily tiotropium bromide.22
EUROPEAN RESPIRATORY DISEASE
Long-acting beta-2 agonists (LABA) have a longer duration of action (>12 hours) and, compared to placebo, these agents are associated with a reduction in severe exacerbations of COPD.21
not affect the rate of decline in lung function (FEV1) or survival.20 Both GOLD and GINA guidelines recommend the use of short-acting beta-2 adrenergic agents for the symptomatic management of patients with COPD with all spectra of severity in COPD4 asthma.3
and
Pulmonary rehabilitation Vaccinations against
influenza and pneumococcus
The number of + signs indicates the strength of data on efficacy; a - sign indicates a lack of the same. COPD = chronic obstructive pulmonary disease.
Figure 2: Forced Expiratory Volume in One Second (ml) for Males, Corrected for Height, Weight and Age at First Survey
4,000
Asthma COPD Overlap Syndrome ++
+++ +/-
+++ ++ +/- ++ ++
+++ ++
+++ ++ –
++
+++ ++
+++ ++ ++ ++ +
++ ++ ++
3,000
2,000
1,000 20 30 40
Non-asthmatic non-smokers Asthmatic non-smokers
50 Age (5 years)
Asthmatic smokers Non-asthmatic smokers
Reprinted with permission of the American Thoracic Society. Copyright © American Thoracic Society.15
FEV1 = forced expiration volume in one second.
However, a large multicentre study that compared salmeterol to placebo in patients with asthma found a trend towards more asthma-related deaths and prompted a black-box warning issued by the US Food and Drug Administration that advised against the use of LABA as first-line therapy for asthma.23
As such, in patients with a
predominant asthmatic component the use of these beta-2 agonists as a single first-line agent should be cautious.
Clinically, anticholinergic agents became the treatment of choice for patients with COPD and beta-agonists for patients with asthma. It appears there might be a paradigm shift in the role of anticholinergics in the treatment of asthma and the overlap syndrome because recent studies showed that tiotropium may be as effective as LABAs in asthma.26
In patients with COPD, the use of 103
Furthermore, the use of such drugs was no more effective than that of inhaled beta-agonists in patients with asthma alone.25
The two anticholinergic agents commonly used include the short-acting ipratropium bromide and long-acting tiotropium bromide. Early studies of short-acting anticholinergic agents, such as ipratropium in heterogeneous groups of patients with both asthma and COPD, showed that adding such drugs to an inhaled beta-agonist alone did not result in significant improvement in lung function or in symptoms in asthmatics.24
60 70 80
FEV (ml)1
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