Background: The last decade has seen a new era of classifications of asthma pathophysiology which have changed the treatment options available.
Objectives: To update the figures of prevalence of T2 asthma, comorbidities, biomarker characterization and costs of severe asthma in patients≥12-years-old adapted to this new situation.
Methods: Retroprospective, observational, nationwide study using a top-down approach. Data were obtained from the BIG-PAC®, an electronic medical record database of 1.7 million patients in Spain. Patients≥12-years-old who had received medical care during the period 2016-2017 and diagnosed with asthma at least one year prior to the index date were included and followed for one year.
Results: Prevalence of asthma was 5.5%. Of these patients, asthma was severe in 3.031 (7.7%), 81.2% of whom presented T2 asthma. Among severe asthma patients, 64·1% were uncontrolled, 31.2% were Oral corticosteroids-dependent (37% in the uncontrolled severe asthma group) and only 3.8% were on biologics. The most common T2 comorbidities were allergic rhinitis (66·1%), atopic dermatitis (29·1%) and chronic rhinositis with nasal polyps (14.6%). Mortality rates in the total and the uncontrolled severe asthma groups were 4.2% and 5.5% respectively. The total annual costs per patient with severe asthma were 5.890€ (uncontrolled) and 2.841€ (controlled).
Conclusions: In the era of biologics, most severe asthma patients present T2 asthma. Despite the availability of new treatments, the rates of uncontrolled and oral corticosteroids-dependent patients with severe asthma remain high, but biologics still underused. The costs of uncontrolled severe asthma are twice as high as those of controlled severe asthma.

Key words: Asthma prevalence, Asthma comorbidities, Asthma costs, Severe asthma, Type 2 asthma, Uncontrolled asthma