Introduction and objectives COPD is the most common chronic lung disease in the developed world yet many patients do not present until they have advanced disease. Screening to identify those with early obstructive airways defects with spirometry may enable earlier treatment and enrolment in smoking cessation programs. Widespread spirometric screening for COPD in the general population is unlikely to be cost-effective. Cardiology inpatients often share similar risk factors to those with COPD; smoking in particular. We hypothesised that screening patients admitted to our coronary care unit would be an effective way of identifying patients at increased risk of developing COPD by using spirometry to detect early obstructive airways defects.
Methods Patients admitted to a coronary care unit at a district general hospital were selected for spirometric assessment. Medically unstable individuals, deemed as those with a modified early warning (MEWS) score of 2 or more were excluded. Forced volume capacity (FVC) and Forced expiratory volume in one second (FEV1) were calculated using a Vitalograph alpha spirometer. The GOLD (Global initiative for Chronic Obstructive Lung Disease) criteria were used to categorise patients according to COPD severity. Those who were found to have airway obstruction were offered repeat testing following discharge.
Results 20 patients were in the initial study population. Four patients were excluded—three because of poor technique and one who had pre-existing COPD. No other patients had any formal diagnosis of respiratory disease. Of the 16 patients, 10 (62.5%) had objective airways obstruction; 6 (37.5%) patients had GOLD stage I, 3 (18.8%) patients GOLD stage II and 1 (6.3%) patient had GOLD stage 3 disease. Of these 10 patients, seven were smokers or ex-smokers. Amongst patients with known ischaemic heart disease, 69.2% had a degree of airways obstruction, whilst 77.8% of patients with a history of smoking had an obstructive picture on spirometry.
Conclusion Coronary care unit inpatients represent an effective target population to screen for potential obstructive airways disease. Identifying patients with ischaemic heart disease and/or a smoking history will allow patients to be risk-stratified further and increase the sensitivity of spirometry. Our study compares favourably with other methods of identifying high risk groups for screening.