Clinical predictors of airway obstruction in primary care

Introduction: Primary care is the frontline for diagnosis and treatment of chronic obstructive pulmonary disease. Airway obstruction (AO) may not be diagnosed, although airflow obstruction is present on spirometry. Thus, a proportion of subject is underdiagnosed. Aims To identify clinical predictors that can induce General Practitioners (GPs) to assess patient's respiratory function through spirometry. Methods: 259 adults (148 M, aged 40-88) attending the GPs' office for a generic consultation, January-June 2014, performed spirometry, IMCA questionnaire. Comorbidities were assessed. We evaluated reported respiratory diagnoses: asthma (A), chronic obstructive pulmonary disease (COPD), asthma plus chronic obstructive pulmonary disease (ACOS). Non respiratory diagnosis (NRD) were subjects not reporting any respiratory diagnosis. For screening purpose a cut-off of FEV1/FVC<70% was considered as marker of AO. AO severity was defined according to ATS criteria. A+COPD+ACOS were considered Respiratory Disease Group. Wheezing, dyspnea, cough or sputum were analyzed. Results: We found: A-8%; COPD-12%; ACOS-4%; NRD-76%. 16% showed AO: 26% in A; 30% in COPD; 43% in ACOS; 10% in NRD. Among NRD 56% reported at least one respiratory symptom. 82% among obstructed NRD. AO severity was: 33% Level 1, 51% Level 2, 16% Level 3. None in Level 4. 69% showed comorbidities. 40% showed cardiovascular diseases. In a logistic multiple regression model, wheezing, male gender, and age >65, were predictors of AO in the NRD, when adjusted for smoking habit (OR=2.76; 3.12; 2.97 respectively). Conclusions In a sample of adults in a primary care setting, wheezing, male gender, and age>65 are predictors of AO. This should suggest to GPs to prescribe spirometry.