Page 67 - Comprehensive treatment of patients with glucocorticoid-dependent severe asthma

perception of asthma symptoms or even more severe airway inflammation [41], which may the cause of failure to control asthma with inhaled medications alone or to discontinue oral corticosteroids after an acute exacerbation.
Finally, psychosocial stress could be the consequence of chronic severe asthma itself. The experience of frequent asthma attacks and/or chronic impairment in social functioning might obviously result in anxiety and depression [42]. However, our results show an association with prednisone dependent asthma and not with severe non-prednisone dependent asthma. Therefore, this explanation is the least likely.
Although this study was performed in a well-defined group of patients and was adequately powered, it might have some limitations. The design of the present study is cross-sectional; therefore, we cannot be certain that the results are consistent over time. Asthma as well as anxiety and depression are conditions with variable degrees of symptoms, and consistency over time in these patients has never been investigated. Nevertheless, the HADS has been well validated in the general population, in general practice and in psychiatric patients [26]. In addition, the HADS has proven to be adequate for repeated assessment of probable anxiety and depression at subsequent visits for follow- up [26].
Second, patients had to use prednisone on a daily basis for at least one month. It could be speculated that, if anxiety and depression are adverse effects of oral corticosteroids, this period may be too short. However, at least one study showed that anxiety and depression can develop within 5 days after starting oral corticosteroids [19]. In addition, the vast majority of our patients used chronic oral prednisone for many years. Therefore, we do not think this influenced the results of the present study.
The results of the present study have clinical and research implications. Physicians should be aware that oral corticosteroids may induce psychiatric adverse effects, such as anxiety and depression which may in turn influence asthma severity and control. Therefore, it might be worth to screen patients with severe prednisone-dependent asthma for anxiety and depression symptoms. In short-term intervention studies promising effects of pharmaceutical or
Anxiety and depression in asthma
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