Severe asthma care trajectories: the French RAMSES cohort.

Background: The French RAMSES study is an observational prospective multicentre real-life cohort including severe asthmatic subjects. The objective of the study was to compare the characteristics of patients, in terms of phenotype and asthma care trajectories, between those managed by tertiary referral centres (TRCs) or secondary care centres (SCCs). Methods: Patients were prospectively recruited and enrolled for a 5-year follow-up. Patients' characteristics were analysed at inclusion and compared between TRCs and SCCs. Results: 52 centres (24 TRCs and 28 SCCs) included 2046 patients: 1502 (73.4%) were included by a TRC and 544 (26.6%) by a SCC. Patients were mainly women (62%), 53±15 years old, 67% with Asthma Control Test <20; at inclusion, 14% received oral corticosteroids (OCS) and 66% biologics. Compared with the SCC group, the TRC group had more frequent comorbidities and lower blood eosinophil counts (262 versus 340 mm-3; p=0.0036). OCS and biologics use did not differ between groups, but patients in the TRC group benefited more frequently from an educational programme (26% versus 18%; p=0.0008) and received more frequently two or more sequential lines of biologics (33% versus 24%; p=0.0105). In-depth investigations were more frequently performed in the TRC group (allergy tests: 74% versus 62%; p<0.0001; exhaled nitric oxide fraction: 56% versus 21%; p<0.0001; induced sputum: 6% versus 3%; p=0.0390). Conclusions: Phenotypes and care trajectories differed in the RAMSES cohort between SCCs and TRCs, probably related to different levels of asthma severity and differences in medical resources and practices among centres. This highlights the need for standardisation of severe asthma care.