The analysis of the different items in patient records showed that history data in some way supported diagnosis in 16.4% of patients with regard to occupational exposure; 37.8% with regard to familiarity for asthma, COPD, or allergy; and 13.3% and 10.2% with regard to previous diagnosis of seasonal or perennial allergy, respectively. Allergy was more frequently registered in asthma patients than in other groups, as expected (21.5% had seasonal and 13.1% had perennial allergy). The frequency of the different risk factors was not significantly different between the two arms of the randomized study. The comparison of respiratory symptoms showed a noteworthy difference between asthma and COPD only for expectoration and chest tightness (Table 4). As for comorbidities relevant to lung chronic obstructive disorders, the most prevalent were rhinitis (24.9% of all patients, 40.2% of asthma patients, 4.1% of COPD patients), sinusitis (9.8%, no significant difference between asthma and COPD), and gastroesophageal reflux (15.1% of patients, 17.5% with COPD vs 8.4% with asthma).
Physical examination of the thorax was normal in 33.8% of patients. Wheezes, ronchi, rales, and crackles were reported in 46.2%, 18.7%, 6.2%, and 6.2% of cases, respectively, without significant differences between the two intervention arms. Normal findings were more common in asthma (33.6%) than in COPD (11.3%) patients. so
In the global patient population, significant ORs (p = 0.02 at least) for diagnostic positive predictive power were found for age > 65 years (OR, 5.65; CI, 2.1 to 15.2), smoking (OR, 5.0; CI, 2.4 to 10.4), and dyspnea (OR, 2.3; CI, 1.1 to 4.6) in the case of COPD. In the differentiation of asthma from COPD, only wheezing (OR, 2.9; CI, 1.6 to 5.4) and allergy (OR, 3.2; CI, 1.6 to 6.6) made a significant positive contribution (p = 0.001 at least).
Considering only patients with concordant diagnosis between GP and specialist, age > 65 years, smoking, and occupational exposure oriented toward COPD with ORs of 11.6 (CI, 1.2 to 113.0), 16.6 (CI, 3.7 to 74.8), and 10.1 (CI, 1.4 to 72.3), respectively (p = 0.03 at least). Allergy and wheezing oriented toward asthma with ORs of 13.0 (CI, 1.7 to 99.2) and 8.7 (CI, 1.9 to 38.7), respectively (p = 0.01 at least).
Table 4—History of Respiratory Symptoms at Enrollment
|Symptoms||GlobalPopulation||Labeled as COPD||Labeled as Asthma|