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Chronic Obstructive Pulmonary Disease – A Contemporary View
Failure to comply with the recommendation for LABD may be one of the systemic corticosteroids, antibiotics, and non-invasive positive
most common treatment errors by primary care practitioners. We are pressure ventilation (NPPV). Systemic corticosteroids reduce treatment
frequently dismayed to care for patients re-admitted to the intensive failures in both in- and outpatient settings, while antibiotics appear
care unit (ICU) after a recent exacerbation of COPD who were more effective in patients requiring hospitalisation. NPPV should be
discharged home from hospital with only an SABD. The fear of LABAs considered for carefully selected patients who demonstrate arterial
may account for this problem. All LABDs appear to be safe in COPD in respiratory acidosis.” The dose of a systemic corticosteroid used for
the absence of ICS. This differs from the treatment of asthma, where treating AECOPDs is controversial. The most commonly cited study of
LABAs (not tiotropium) are approved only in combination with an ICS severe exacerbations used a high dose – 125mg of methylprednisolone
and are recommended only after ICS have been found to inadequately every six hours for three days followed by a tapering course.
18
Other
control symptoms. A systematic review of the safety of LABAs in stable studies have used a lower dose. We usually recommend 1–2mg/kg/day
COPD concluded that they showed a 19% reduction in all-cause in divided doses, with a tapering course over two weeks. Antibiotic
mortality associated with the use of single-agent salmeterol (p=0.004).
14
choice often includes a fluoroquinolone or a macrolide, but choices are
We suspect that the US Food and Drug Administration’s (FDA) decision complex and vary depending on local patterns of resistance and
in late 2008 to remove the asthma indication for single-agent LABAs has patient-specific risk factors for treatment failure.
the effect of preventing physicians from appropriately using LABAs in
COPD. In contrast, it may further increase the use of combined Should We Screen for Chronic
LABA–ICS products and thus enhance the observed tendency of ICS Obstructive Pulmonary Disease?
overuse in COPD.
15
The Lung Health Study
2
(LHS) randomised current smokers with mild to
moderate COPD to a smoking cessation programme or usual care.
The Understanding Potential Long-Term Impacts on Function with Approximately 60,000 persons were tested in order to randomise about
Tiotropium (UPLIFT) trial assessed the effects over four years of the long- 6,000 participants. After five years of study, about 40% of the ‘special
acting anticholinergic tiotropium in nearly 6,000 persons with moderate intervention’ group had quit smoking. Twenty-two per cent had quit and
to very severe COPD. While tiotropium failed to meet the study’s primary remained quitters at each annual visit for five years. In the ‘usual care’
end-point of reducing the overall rate of FEV
1
decline, it showed group, only 7% were sustained quitters. Analysis of lung function data
significant improvements in post-bronchodilator FEV
1
and rate and showed that randomisation to the smoking cessation group was
frequency of acute exacerbations. More interestingly, the addition of associated with improved lung function at the end of the study. Among
tiotropium led to an early and sustained improvement of FEV
1
and FVC in those who quit smoking, lung function improved slightly in the first year
the 50–100ml range compared with the placebo group throughout the and then stabilised to a normal rate of decline (approximately 30ml
study period. This suggests an additive effect of tiotropium on LABA or decrease in FEV
1
per year). In comparison, those who continued
LABA–ICS therapy. Previously expressed concerns for an increased risk of smoking had no improvement in lung function in the first year, and their
strokes and cardiovascular events were not substantiated by the trial.
16
lung function declined at twice the normal rate (60ml per year) in
subsequent years. Interestingly, the benefits of smoking cessation were
We would point out that there is little evidence to justify the use of broadly distributed among those who quit, so that advanced age, lower
LABD for FEV
1
>65% predicted. Below that level of lung function, lung function, more reactive airways and heavier smoking did not
the evidence is excellent and there are several studies currently preclude the benefits of smoking cessation. Common excuses for not
active to address the milder condition. quitting (e.g. ‘I’m too old’, ‘I smoked too much’ and ‘My lungs are shot’)
turned out to be invalid.
19
Severe COPD (stage III, FEV
1
<50% predicted) is present in about 10%
of those with COPD, and accounts for the bulk of morbidity and Spirometry at 11-year follow-up testing showed that the rates of
mortality from the disease (although the risk of lung cancer and heart decline observed among continuing smokers and sustained quitters
disease does not scale with the severity of COPD). In severe COPD, persisted unchanged. Of greater interest, the development of severe
AECOPDs are more common, and symptoms and quality of life are COPD (FEV
1
<50% predicted) occurred in 18% of continuing smokers
more severely affected. If post-bronchodilator FEV
1
is found to be compared with only 3% of sustained quitters, a six-fold reduction in this
<50%, arterial blood gas (ABG) levels should be assessed, as chronic highly morbid outcome.
20
Long-term survival was tracked in the LHS
hypoxic or hypercapnic respiratory failure may have already cohort for 17 years. After 14 years it was shown that randomisation to
developed. An FEV
1
<50% also warrants consideration of a referral to the special intervention group was associated with a significant
a pulmonary specialist to help guide management. improvement in survival. Of perhaps greater interest, the comparison of
sustained quitters versus continuing smokers showed that all-cause
Very severe COPD (stage IV, FEV
1
<30% predicted or any reduction in mortality in the sustained quitters was 7.4 versus 12.6% in the
FEV
1
and the presence of chronic respiratory failure on ABG) requires continuing smokers – a 41% reduction. Based on these data, it is
assessing the patient for the need for supplemental oxygen. Oxygen legitimate to tell a current smoker with mild to moderate COPD that by
therapy improves survival of persons with chronic hypoxia. quitting smoking he or she can expect to reduce the risk of death over
Supplemental oxygen is recommended if pressure of oxygen in arterial 14 years by over 40%.
21
blood (PaO
2
) is <55mHg or oxygen saturation is <88% at rest. The goal of
oxygen supplementation is to achieve PaO
2
of >60mmHg and/or oxygen Based on the results of the LHS, the National Lung Health Education
saturation >90%. Surgical options such as lung reduction surgery, Program made the recommendation that smokers or ex-smokers >45
bullectomy, or lung transplantation may be considered at this stage. years of age should be screened for airway obstruction with
spirometry.
22
The problem with that recommendation, other than the
The treatment of AECOPDs was recently reviewed critically by Quon et cost of screening several million people in the US alone, is that it is not
al.,
17
who stated that: “AECOPDs may be treated effectively with clear exactly what benefit would be achieved. Screening could
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