Clinical remission at two years post-diagnosis of asthma and its association with clinical outcomes: A retrospective cohort study in asthma patients with maintenance inhaler therapy

Abstract

Clinical remission (CR) has emerged as a potential therapeutic goal in patients with severe asthma eligible for biologic agents. However, its impact on long-term outcomes in asthma patients managed with maintenance inhaler therapy remains unclear. In this retrospective cohort study, we evaluated adult asthma patients on maintenance inhalers to investigate the long-term outcomes associated with achieving CR. CR was defined as at least one year without exacerbations, well-controlled symptoms, no use of systemic corticosteroids, and stable lung function, assessed two years after asthma diagnosis. We compared the trajectory of forced expiratory volume in 1 s (FEV₁) and the annual rate of exacerbations between CR and non-CR groups in a 1:1 propensity score-matched population. Among 549 patients followed for a median of 7 years, 88 (16 %) met the criteria for CR. After matching, 76 patients were included in each group. Compared to the non-CR group, the CR group showed a significantly lower proportion of patients with annual FEV₁ decline exceeding 60 mL (8.6 % vs. 25 %, P = 0.010). A linear mixed-effects model showed that the CR group had a significantly slower rate of FEV1 decline, with an annual difference of 32.7 mL (95 % CI 6.7 to 58.7; P = 0.014) compared with the non-CR group. The CR group also had a lower annual rate of moderate-to-severe exacerbations (0.17 events/year [IQR 0, 0.37] vs. 0.42 events/year [IQR 0, 1], P = 0.007). In conclusion, achieving CR in asthma patients receiving maintenance inhaler therapy was associated with a slower decline in lung function and fewer exacerbations. These findings support the potential role of CR as a long-term therapeutic goal.