Quality data for 2005/6 indicate that 1.7 per cent of the UK population has COPD.
But the true figure could be as high as 4 per cent, according to a study of 13,654 patients by the general practice research unit at the North West Lung Research Centre in Manchester.
A diagnosis of COPD, as indicated by spirometry results, was made in 552 of the participants, giving a COPD prevalence of 4 per cent for the total population.
The estimated prevalence was then calculated for different age groups, ranging from 30 to 80 years of age.
The findings reinforce previous calls to screen individuals over the age of 40 for COPD - prevalence was 9.6 per cent in those over the age of 40, and as high as 14.7 per cent in those aged 60-69.
Between 30 and 39 there was a COPD prevalence of just 0.5 per cent, however.
Lead researcher Dr Timothy Frank said a combination of factors was to blame for the under-diagnosis of COPD.
'Patients with COPD may not be visiting their GP because their symptoms are not causing them any problems,' he said.
'Those who do attend may be treated for coexisting or alternative medical complaints such as asthma and chest infections, so spirometry is not performed and a diagnosis is not made.'
Dr Frank said it was important that the research split its findings into age bands because previous prevalence estimates had related to the whole population, and failed to reveal how common the disease was in older age groups.
Dr Steve Holmes, a Somerset GP and chairman of the Gen-eral Practice Airways Group, said the research strengthened the view that cases of COPD were continuing to go undiagnosed.
'Evidence suggests 60-70 per cent of people with COPD are still being missed,' he said.
'We need a more robust system of screening and diagnosis to help pick up these cases.'
Dr Holmes suggested that differences in the way the quality framework diagnoses COPD, compared with the NICE and the Global Initiative for COPD (GOLD) methods of diagnosis, might have contributed to the lower levels of COPD prevalence recorded under the quality framework.What do you think? Comment below or email us at email@example.com