Over-prescription of short-acting β2-agonists is associated with poor asthma outcomes: results from the African cohort of the SABINA III study

Background The extent of short-acting β2-agonist (SABA) overuse in Africa remains poorly documented. As part of the SABA use IN Asthma (SABINA) III study, we assessed SABA prescriptions/clinical outcomes in 3 African countries. Methods Data on disease characteristics/asthma treatments were collected from patients (≥12 years) using electronic case report forms. Patients were classified by investigator-defined asthma severity (guided by the 2017 Global Initiative for Asthma) and practice type (primary/specialist care). Multivariable regression models analyzed associations between SABA prescriptions and outcomes. Results Data from 1778 patients (mean age, 43.7 years) were analyzed. Most patients were female (62.4%) and had moderate-to-severe asthma (63.3%), with 57.1 and 42.9% of patients treated in specialist and primary care, respectively. Asthma was partly controlled/uncontrolled in 66.2% of patients, with 57.9% experiencing ≥1 severe exacerbation in the previous 12 months. Overall, 46.5% of patients were prescribed ≥3 SABA canisters in the preceding 12 months (over-prescription); 26.2% were prescribed ≥10 canisters. SABAs were purchased over-the-counter by 32.6% of patients, of whom 79.3% had received SABA prescriptions; 71.9% and 40.1% for ≥3 and ≥10 canisters, respectively. Higher SABA prescriptions (vs. 1–2 canisters) were associated with increased incidence rate of severe exacerbations and lower odds of having at least partly controlled asthma (except 3–5 canisters). Conclusions Findings from this African cohort of the SABINA III study indicate that SABA over-prescription and SABA over-the-counter purchase are common and associated with poor asthma-related outcomes. This highlights the need for healthcare providers/policymakers to align clinical practices with the latest treatment recommendations

TRAV1-2⁺ CD8⁺ T-cells including oligoconal expansions of MAIT cells are enriched in the airways in human tuberculosis

Mucosal-associated invariant T (MAIT) cells typically express a TRAV1-2+ semi-invariant TCRα that enables recognition of bacterial, mycobacterial, and fungal riboflavin metabolites presented by MR1. MAIT cells are associated with immune control of bacterial and mycobacterial infections in murine models. Here, we report that a population of pro-inflammatory TRAV1-2+ CD8+ T cells are present in the airways and lungs of healthy individuals and are enriched in bronchoalveolar fluid of patients with active pulmonary tuberculosis (TB). High-throughput T cell receptor analysis reveals oligoclonal expansions of canonical and donor-unique TRAV1-2+ MAIT-consistent TCRα sequences within this population. Some of these cells demonstrate MR1-restricted mycobacterial reactivity and phenotypes suggestive of MAIT cell identity. These findings demonstrate enrichment of TRAV1-2+ CD8+ T cells with MAIT or MAIT-like features in the airways during active TB and suggest a role for these cells in the human pulmonary immune response to Mycobacterium tuberculosis