The Specialist Forum May 2017 | Page 10

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PULMONOLOGY
Regular treatment with inhaled corticosteroids improves symptoms , lung function , and quality of life , and reduces the frequency of exacerbations in COPD patients with an FEV1 < 60 % predicted .
occur within the therapeutic range of serum theophylline .
These medications also have significant interactions with commonly used medications such as digitalis , coumadin , etc . Unlike the other bronchodilator classes , xanthine derivatives may involve a risk of overdose ( either intentional or accidental ).
Combination bronchodilator therapy
Combining bronchodilators with different mechanisms and durations of action may increase the degree of bronchodilation for equivalent or lesser side effects . For example , a combination of a short-acting beta 2
-agonist and an anticholinergic produces greater and more sustained improvements in FEV1 than either drug alone and does not produce evidence of tachyphylaxis over 90 days of treatment .
The combination of a beta 2
- agonist , an anticholinergic , and / or theophylline may produce additional improvements in lung function and health status . Short-term combination therapy using formoterol and tiotropium has been shown to have a bigger impact on FEV1 than the single components . Combinations of shortacting beta 2
-agonists and anticholinergics are also superior compared to either medication alone in improving FEV1 and symptoms . Combinations of a long-acting beta 2
-agonist and a long-acting anticholinergic have shown a significant increase in lung function whereas the impact on patient reported outcomes is still limited .
There is still too little evidence to determine if a combination of long-acting bronchodilators is more effective than a longacting anticholinergic alone for preventing exacerbations .
Corticosteriods Inhaled corticosteroids
The dose-response relationships and long-term safety of inhaled corticosteroids in COPD are
not known . Only moderate to high doses have been used in long-term clinical trials . The efficacy and side effects of inhaled corticosteroids in asthma are dependent on the dose and type of corticosteroid , but whether this is also the case in COPD is unclear . The effects of corticosteroids on pulmonary and systemic inflammation in patients with COPD are controversial , and their role in the management of stable COPD is limited to specific indications .
Regular treatment with inhaled corticosteroids improves symptoms , lung function , and quality of life , and reduces the frequency of exacerbations in COPD patients with an FEV1 < 60 % predicted .
Withdrawal from treatment with inhaled corticosteroids may lead to exacerbations in some patients , although in another study with severe and very severe COPD patients , inhaled corticosteroids could be gradually withdrawn over a three- month period without increasing the medium term risk of exacerbations , although lung function deteriorated significantly .
Withdrawal of inhaled corticosteroids , in COPD patients at low risk of exacerbation , can be safe provided that patients are left on maintenance treatment with long-acting bronchodilators . Regular treatment with inhaled corticosteroids does not modify the long-term decline of FEV1 nor mortality in patients with COPD .
Combination inhaled corticosteroid / bronchodilator therapy
An inhaled corticosteroid combined with a long- acting
beta 2
-agonist is more effective than the individual components in improving lung function and health status and reducing exacerbations in patients with moderate to very severe COPD .
An inhaled corticosteroid / longacting beta 2
-agonist combination given once daily does not show
relevant differences regarding efficacy compared to twice daily . A large prospective clinical trial failed to demonstrate a statistically significant effect of combination therapy on mortality , but a subsequent meta-analysis found that combination therapy may reduce mortality with a number needed to treat ( NNT ) of 36 254 .
Combination therapy is associated with an increased risk of pneumonia , but no other significant side effect . The addition of a long-acting beta 2
- agonist / inhaled corticosteroid combination to tiotropium improves lung function and quality of life and may further reduce exacerbations , but more studies of triple therapy are needed .
Oral corticosteroids
Oral corticosteroids have numerous side effects . An important side effect of longterm treatment of COPD with systemic corticosteroids is steroid myopathy , which contributes to muscle weakness , decreased functionality , and respiratory failure in subjects with very severe COPD .
In view of the well-known toxicity of long-term treatment with oral corticosteroids , prospective studies on the long-term effects of these drugs in COPD are limited . However , systemic corticosteroids for treating acute exacerbations have been shown to improve symptoms , lung function , reduce rate of treatment failure , and shorten length of hospital stay .
The effect of preventing a subsequent exacerbation has been shown in a pooled data analysis and it was demonstrated that systemic corticosteroids when being used to treat acute exacerbations can reduce 30- day readmission rates due to recurrent exacerbations .
Phosphodiesterase-4 inhibitors
The principal action of
10 | May 2017
The Specialist Forum | Vol . 17 No . 4