The Italian severe/uncontrolled asthma registry (RItA): a 12-month clinical follow-up

Background: follow-up studies on registries of severe/uncontrolled asthma (SUA) patients are scanty. Objective: to analyze baseline and follow-up characteristics of SUA patients and their longitudinal patterns. Methods: 180 adult patients (age >=15 yrs) were investigated at baseline and 12-month follow-up through the Italian SUA registry (RItA). Latent transition analysis (LTA) was performed to detect cross-sectional SUA phenotypes and longitudinal patterns. Risk factors for longitudinal patterns were assessed through logistic regression. Results: a significant/borderline improvement of asthma control outcomes in the last 2-4 weeks emerged at follow-up with respect to baseline for: daily activities limitations (? - 16%), frequent diurnal symptoms (?- 25%), uncontrolled asthma symptoms according to ACT (? - 26%). Last 12-month use of oral corticosteroids was less frequent at follow-up than at baseline (? - 25%). Health status improvement was confirmed by lung function test results. Through LTA, two longitudinal patterns were detected considering last 12-month control outcomes: "persistence/worsening" (53.9%), "under control/improvement" (46.1%). A lower likelihood of having "persistence/ worsening" SUA was exhibited by patients under anti-IgE (OR 0.38, 95% CI 0.17-0.84) and inhaled corticosteroids-bronchodilator association treatment (OR 0.13, 95% CI 0.01-1.26, borderline value), while a higher likelihood was shown by older age at first asthma diagnosis (OR 1.04, 95% CI 1.01-1.07). Conclusion: the implementation of a SUA registry, the availability of patient-level data and the application of an innovative longitudinal analysis allowed to observe a general improvement in asthma control, one year after baseline, and a lower risk of SUA "persistence/worsening" in patients under anti-IgE and regular ICSbronchodilator association use.