Those 236 GPs who after run-in continued to use the spirometer for purposes of the observational study enrolled 2,055 patients (mean, 8.7 ± 2.6 patients per GP; median, 10; range, 1 to 19; 54% male; mean age, 51.4 years [range, 7 to 95 years]; 31% smokers; 16% former smokers of whom 45% without a known diagnosis [3% missing data]). Of the 52% with a known diagnosis, 34.4% had COPD and 37.5% had asthma. Median time for instruction of patients was 5 min (range, 1 to 60 min), and time for performance was 6 min (range, 1 to 50 min). The enrollment trend is shown in Figure 2. After 5 months, when 74% of patients had been recruited, the rate of enrollment began to decrease sharply and reached a minimal number of 16 patients (0.8% of total) in the last month of the study. The final questionnaire on the usefulness of office spirometry gave the following results: 57.1% very useful, 15% moderately useful, 0.3% useless, and 27.6% no reply. As compared to the same questionnaire administered immediately after the run-in phase (see above), there was a sharp decrease in the number of “very useful” responses, with an abstention rate of 27.6% not registered in the earlier questionnaire. read
Subjects with chronic respiratory disorders frequently have delayed access to diagnostic evaluation and treatment, in many cases because patients themselves minimize their symptoms and do not consult their GP. An ongoing debate in respiratory medicine focuses on whether the performance of spirometry by the GP may help in identifying asthma or COPD patients earlier, offering them a correct treatment even though specialist assessment is not readily available. The aim of our study was to verify on a large scale whether the performance of spirometry in the GP’s office is feasible and constitutes a better mode for reaching a correct diagnosis of asthma or COPD than a conventional evaluation (including a thorough case history and physical examination) alone. The type of agreement with GPs and the resources allowed for this study did not allow to carry out a case-finding study; therefore, only patients with one or more respiratory symptoms were included in the study, although it is well known that adult current or former smokers who do not report any respiratory symptoms (at least on a questionnaire) still have a 15 to 30% risk of COPD (depending on age and gender).
Figure 2. Enrollment trend (number of patients per month) during the 9 months of the observational study.