Characteristics and treatment escalation of severe uncontrolled asthma patients in primary care in Sweden

<bold>Background:</bold> There is limited data exploring the outcomes of severe asthma patients in primary care in Sweden. <bold>Aim:</bold> To describe characteristics of severe asthma patients in primary care, stratified by asthma control, and to investigate treatment transitions and hospitalization in uncontrolled patients. <bold>Methods:</bold> This study included 29,760 primary care asthma patients ≥18 years with a recording in the Swedish National Airway Register between July 2017-February 2019 (index date). Data was linked to the drug registry to obtain treatment 12 months pre- and post-index date. Severe asthma was defined as GINA step 4-5, with a medication possession ratio ≥80%. Asthma Control Test ≤19 was defined as uncontrolled asthma. Hospitalization (ICD-10 J45/J46) and use of oral corticosteroids (OCS), defined as ≥2 pharmacy claims, were investigated. <bold>Results:</bold> Severe asthma was identified in 9.4% (<italic>n</italic>=2789). In patients with uncontrolled disease (<italic>n</italic>=1261), 91% were in step 4. Uncontrolled patients were more often women (66.5% vs 59.0%), had a higher BMI (28.9 vs 27.5), lower FEV1%pred (79.6 vs 82.9) and higher OCS usage (19.9% vs 11.9%) compared to well-controlled patients (all p<0.001). Hospitalization due to asthma in the uncontrolled group increased from 7.9% to 8.7% post-index, whereas hospitalization in the well-controlled group decreased from 4.0% to 3.7% post-index. In the uncontrolled group, 55% remained on the same treatment step, 40% stepped down and 5% escalated treatment during post-index. <bold>Conclusions:</bold> Our data highlights the unmet need of severe uncontrolled asthma patients in primary care. Only 5% escalated treatment despite high OCS usage and increased hospitalizations during follow-up.