Page 34 - Comprehensive treatment of patients with glucocorticoid-dependent severe asthma

Chapter 2
disease (COPD), alpha-1 antitrypsin deficiency, cystic fibrosis, cardiomyopathy, obliterative bronchiolitis, dysfunctional breathing and vocal cord dysfunction [5]. Another study showed that such additional diagnoses could even be detected in more than half of the patients with therapy resistant asthma [6]. Therefore, every patient with asthma who does not seem to respond to high- intensity asthma treatment should undergo objective tests to exclude other diseases and confirm the diagnosis of asthma.
Non-adherence to therapy
Adherence to anti-inflammatory treatment is low in patients with chronic diseases such as asthma [7-10], and is an important cause for loss of asthma control [10]. In a recent pragmatic trial evaluating the real-world effectiveness of a leukotriene-receptor antagonist in uncontrolled moderately severe asthma, the median adherence of patients to the use of inhaled steroids was as low as 40% [11]. Non-adherence is also a major issue in patients at the more severe spectrum of the disease. In a study by Robinson and colleagues, 50% of subjects with 15 mg prednisolone prescribed per day had either non- detectable serum prednisolone or normal cortisol levels [5], and a study by Gamble and colleagues showed that 45% of patients with prescribed oral steroids were found to be non-adherent using objective measures [8].
Adherence to asthma medication can be improved. Self-reporting is usually unreliable and it has been described that patients only admitted low adherence when confronted with objective measurements such as medication adherence questionnaires (Medication Adherence Rating Scale (MARS) [12], assessment of prescription refill record [8;13] or measurement of serum or urinary cortisol levels [5;8;14]. Confronting the problem in a medical concordance interview can lead to sustained behavioral changes as has been shown in a randomized controlled pilot study in patients referred to a specialized centre with low adherence as the primary cause of difficult-to control asthma [15]. Since many patients do not take their medication because they perceive it to be unnecessary or because they are concerned about potential adverse effects [16;17], these issues should be addressed systematically in every patient with severe asthma.
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