Background This study evaluated the efficacy of a mindfulness training programme (mindfulness-based stress reduction (MBSR)) in improving asthma-related quality of life and lung function in patients with asthma.

Methods A randomised controlled trial compared an 8-week MBSR group-based programme (n=42) with an educational control programme (n=41) in adults with mild, moderate or severe persistent asthma recruited at a university hospital outpatient primary care and pulmonary care clinic. Primary outcomes were quality of life (Asthma Quality of Life Questionnaire) and lung function (change from baseline in 2-week average morning peak expiratory flow (PEF)). Secondary outcomes were asthma control assessed by 2007 National Institutes of Health/National Heart Lung and Blood Institute guidelines, and stress (Perceived Stress Scale (PSS)). Follow-up assessments were conducted at 10 weeks, 6 and 12 months.

Results At 12 months MBSR resulted in clinically significant improvements from baseline in quality of life (differential change in Asthma Quality of Life Questionnaire score for MBSR vs control: 0.66 (95% CI 0.30 to 1.03; p<0.001)) but not in lung function (morning PEF, PEF variability and forced expiratory volume in 1 s). MBSR also resulted in clinically significant improvements in perceived stress (differential change in PSS score for MBSR vs control: −4.5 (95% CI −7.1 to −1.9; p=0.001)). There was no significant difference (p=0.301) in percentage of patients in MBSR with well controlled asthma (7.3% at baseline to 19.4%) compared with the control condition (7.5% at baseline to 7.9%).

Conclusions MBSR produced lasting and clinically significant improvements in asthma-related quality of life and stress in patients with persistent asthma, without improvements in lung function.

Clinical Trial Registration Number Asthma and Mindfulness-Based Reduction (MBSR) Identifier: NCT00682669. clinicaltrials.gov.