Early studies

Treatment of COPD with ICS has until recently not been evidence-based, no matter how that term is defined. This is reflected in findings from literature searches on the topic, with more editorials and comments being published than original papers. It is worth bearing in mind that there can be several reasons for choosing to treat COPD with ICS. Crudely, one can simply aim to relieve symptoms in COPD, or one can have the more ambitious goal of altering the future course of the disease. This may seem too simplistic, but the aim of treatment must be made clear. Whereas ICS, by diminishing acute inflammatory changes in the airways, can reduce cough, mucus hypersecretion, and perhaps even dyspnoea, the more ambitious long-term aim would be to alter the course of the disease, and most often this would imply reducing the excess decline in forced expiratory volume in 1s (FEVj), which is the hallmark of COPD. It would be fair, however, to state that a marked effect on other aspects of the disease — e.g. the number of exacerbations requiring medical treatment—would be beneficial and could be said to affect the course of the disease, although exacerbations are not traditionally considered significant in the natural history of the disease [2]. Recent analyses in the Lung Health Study [3] have shown that exacerbations result in an excess decline in FEV1 that is not recovered later, and similar findings have been reported in abstract form by a British group [4].

Regarding the relief of symptoms, the data are not impressive. Data on the effect of ICS on FEV1 decline are also limited, and leave much room for different interpretations. The most important studies will be briefly mentioned below.

Very often the early findings of Postma et al. [5,6] are quoted. These were uncontrolled studies of long-term treatment with low/moderate doses of systemic corticosteroids. The studies were not trials of medication, but observational studies from an ongoing epidemiological panel study in the towns of Vlagtwedde and Vlaardingen in the Netherlands, and no placebo-controlled long-term studies of oral corticosteroids exist. Few controlled long-term studies of inhaled corticosteroids in COPD have been conducted until recently. Kerstjens et al. [7] showed an effect on both FEV1 and exacerbations. From today's point of view, the study is limited, because the Dutch at the time when the study was initiated seemed to make less distinction between asthma and COPD than is generally considered correct, judging from recent guidelines on asthma and COPD. This distinction between asthma and COPD was more obvious in the smaller study by Renkema et al. [8] from 1996. Their study showed some effect of inhaled corticosteroids on FEV1, but the power of the study was limited. Recently, a meta-analysis [9] of the studies by Kerstjens et al. [7] and Renkema et al. [8], together with a study published as an abstract only [10] has appeared. The meta-analysis, by van Grunsven et al., showed an estimated 2-year difference in prebronchodilator FEV1 between subjects treated with inhaled corticosteroids and placebo of 34mL/year; this was statistically significant, in spite of the fact that approximately one-third of the patients originally included were excluded from the meta-analysis. The effect on postbronchodilator FEV1 was less impressive, and the time course of FEV1 did not fit in with our general understanding of the time course of the decline of FEV1 in COPD. In a smaller Canadian study of 77 COPD patients irreversible

Table 10.1 Recent controlled trials of inhaled corticosteroids in chronic obstructive pulmonary disease.

Study

Ref.

Total number

Disease severity

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