The diagnostic accuracies of chronic obstructive pulmonary disease (COPD) in general practice: the results of the MAGIC (Manchester Airways Group Identifying COPD) study

Abstract

Although it is generally accepted that chronic obstructive pulmonary disease (COPD) is underdiagnosed, there is little objective information concerning the size of the problem in the UK. Patients from two general practices were offered spirometry if they were aged 30 or older, had reported ever smoking in one of four postal respiratory surveys (1993-2001), and/or reported four or more symptoms or risk factors in 2001 indicating likely obstructive airways disease. Of 2646 subjects invited, 871 attended and 825 had adequate spirometry results for analysis. In all, 163 patients had spirometrically-confirmed COPD; 103 of these (63.2%) had no recorded COPD in their practice records, including 14 out of 31 (45.2%) whose spirometry results classified them as having severe or very severe COPD. This study found a considerable under-recording of COPD in two general practices. This may be due to a combination of administrative and diagnostic problems (including the under-use of spirometers), and a reluctance of patients to present with their symptoms. These results have important implications in terms of unmet need and resource utilisation.