Validity of spirometry performed in the primary care setting

Background: Spirometry is a valuable diagnostic tool in the identification of patients with Chronic Obstructive Pulmonary Disease (COPD) in the community.In the primary care setting, low acceptability of spirometric manoeuvres has been reported which may affect the interpretation of results and clinical decision making. T R Schermer et al had demonstrated in the Netherlands that spirometric indices performed by trained general practice staff were marginally but statistically significantly higher than those measured in pulmonary function laboratories. He concluded laboratory and general practice values should not be used interchangeably. Aims: To evaluate the validity of spirometric testing performed in the community. Methods: Retrospective study of 405 patients found to have abnormal screening spirometry performed in the community. Screening criteria included adults with a history of smoking. This was followed by repeat spirometry in the hospital pulmonary function laboratory. Data was analyses using SPSS. Results: N=405, mean age 54 years (range 22 to 78), 46 % (187) and 41% (165) were current and ex-smoker respectively. 78% (318) were using short-acting beta agonist 60% (242) were already on inhaled steroids.0.7% (3) were on oral steroids. 82% (331) had obstructive spirometry. Majority (45%) of them had moderate COPD. 32% and 11% were found to have severe and very severe COPD respectively. The Mean FEV1 in the community (1.52 liters) was slightly higher than the pulmonary function laboratory (1.49 liters).Paired t test study showed the results to be in concordance to the results demonstrated by T R Schermer et al. Conclusions: This study validates the results published in the Netherlands by T R Schermer et al.