By Daniel Cressey
GPs are to gain a valuable new tool in the diagnosis of COPD
after an international team
of researchers validated a new scoring system for primary care.
The system uses two simple questionnaires to identify smokers likely to have COPD and facilitate their diagnosis. Both have good sensitivity and specificity for the disease, a study in the latest issue of Chest reports.
The questionnaires, whose development was reported by Pulse in January, have been added to the International Primary Care Airways Group's chronic respiratory disease guideline and are next likely to be considered by NICE.
Professor David Price, one of the researchers on the new study and professor of primary care respiratory medicine at the University of Aberdeen, said: 'We see at least two potential applications – improving the efficiency of COPD diagnosis in smokers who present with respiratory symptoms but no prior diagnosis, and assisting in early detection of COPD in smokers outside clinical settings.'
Fellow researcher Dr Ronald Halbert, adjunct associate professor in the department of community health sciences at the University of California, US, said: 'These are the most scientifically rigorous COPD diagnostic questionnaires available, and the only ones developed specifically for use by GPs.'
The researchers assessed the first, case-finding, questionnaire in 818 patients, using cut-off scores of 16.5 and 19.5 to demarcate patients at low, intermediate and high risk. The cut-offs gave sensitivities of 58.7 and 80.4 per cent and specificities of 77.0 and 57.5 per cent (see box).
The differential diagnosis questionnaire in 597 patients, using cut-offs of 19.5 and 24.5, gave sensitivities of 53.8 and 82.1 per cent, and specificities of 88.2 and 63.7 per cent.
Dr Steve Holmes, chair of General Practice Airways Group and a GP in Shepton Mallet, Somerset, said: 'It would be useful. We know we are grossly underdiagnosing COPD.'
Question Items Score
Age group, yr
40-49 (reference) 0
Body mass index, kg/m2
Smoking intensity, pack-yr
0-14 (reference) 0
Weather affects cough 3
Phlegm without a cold 3
No phlegm in the morning 3
Wheeze frequency (any) 4
Have or had any allergies 3 (no)
< 16.5="" low="">
>19.5 high risk