INTEREST IN BREATHING EXERCISES

One third of patients with asthma have tried some form of breathing exercises to help control symptoms. However, the evidence base for these treatments is limited. Cooper et al in this month’s Thorax evaluate two of these exercises in a placebo controlled trial—the Buteyko method which focuses on ventilation control and a device that mimics pranayama (a yoga breathing technique). Some improvement was seen in symptoms and bronchodilator use in patients using the Buteyko method, although the use of bronchodilators is actively discouraged with this technique. However, the Buteyko method had no effect on airway calibre, bronchial responsiveness, or exacerbations. As Thomas points out in the accompanying editorial, many asthmatic patients will want to try these treatments but more evidence is required to confirm their effectiveness and to clarify mechanisms. See pages 649 and 674

LESSONS FROM ISOLDE

COPD is a difficult condition—not only because of its clinical heterogeneity, but also because assessment has often been confusing. In this issue of Thorax we publish two further papers from the ISOLDE study of long term inhaled steroids in COPD. As Gross points out in the accompanying editorial to the papers, the availability of this large data set in a carefully executed trial allows the opportunity to evaluate other basic questions. These important papers examine the issues of reversibility to prednisolone and bronchodilators, topics that have caused much previous debate.

The protocol of the ISOLDE study included a 2 week prednisolone trial before randomisation and thus provided a unique opportunity to evaluate the effects of steroid trials in COPD in large patient numbers. Burge and colleagues showed that the steroid response was unimodally distributed, with no separation into responder and non-responder groups and, in addition, that the response had no effect on long term outcome. Calverley and colleagues found that an individual bronchodilator response did not predict future response. The important lesson is that we should not rely on steroid and bronchodilator responsiveness for disease assessment, and this should now be incorporated into COPD guidelines. Furthermore, as Gross points out, it is time to stop using bronchodilator response as an entry criterion into clinical trials. See pages 647, 654 and 659

LUNG FUNCTION AND CARDIOVASCULAR RISK

There is now evidence that a reduced FEV₁ may be a risk factor for cardiovascular disease, independent of the effects of smoking. Atherosclerosis is associated with systemic inflammation and thus leptin, a hormone produced by adipose tissue, may play a part in this inflammatory process. Leptin is proinflammatory and increases platelet activity. In this issue Sin and Man show a relationship between impaired lung function and raised serum leptin levels in a non-obese population, independent of other risk factors. The only drawback of the study is that patients with more severely impaired FEV₁ were not studied, and it is these patients who are most susceptible to the proinflammatory effects of leptin. See page 695

SUBOPTIMAL CARE FOR LUNG CANCER

Men in south west Sydney, New South Wales (NSW) have higher mortality from lung cancer than the NSW average. In this issue of Thorax Vinod and colleagues describe a study which examined patterns of care for lung cancer to see if the differences in mortality could be explained by deficiencies in care. A significant number of the patients never saw a specialist and 28% never received any active treatment. Rate of referral and treatment decreased with increasing patient age. The results of this study emphasise the importance of referral to specialist lung cancer units to improve management and outcome. See page 690