We aimed to evaluate asthmatic patients with fixed airways obstruction (FAO) and to verify the impact of follow-up in an asthma-dedicated outpatient clinic on symptoms control and spirometry compared to asthmatics without FAO. We enrolled 20 asthmatic FAO+ patients and 20 FAO- asthmatics at baseline (T0) and at a one-year follow-up visit (T1). FAO+ and FAO- groups were compared for anamnesis, FEV1, asthma control test (ACT) and their ΔT0-T1. FAO+ and FAO- groups did not differ for age, BMI, pack-years, allergy, T0 blood eosinophils, comorbidities or GINA therapy step at T0 and T1, whereas, in the FAO+ group, we found more patients with a delay >5 years between symptoms onset and correct asthma diagnosis (p < 0.05). ACT at T0 and ΔT0-T1, FEV1 at ΔT0-T1 and number of exacerbations at T0 and ΔT0-T1 did not differ between groups. Despite a widespread perception of FAO, per se, as a severity factor for asthma, we found similar severity profiles and amelioration after one year of treatment in the FAO+ and FAO- groups. The only factor linked to FAO development in our population was a delay in asthma diagnosis from respiratory symptoms onset, which may have led to airway remodeling. Physicians should characterize patients with FAO for avoiding misdiagnosis between asthma and other respiratory diseases and for establishing the appropriate therapy.
Keywords: airways obstruction; asthma; fixed obstruction; severe asthma.