Association of GLP-1-based therapy with asthma-related outcomes in patients with obesity: a propensity-matched retrospective cohort study.

BACKGROUND: Obesity worsens asthma morbidity, but observational associations between glucagon-like peptide-1 (GLP-1)-based therapy and respiratory outcomes may be confounded by treatment selection. RESEARCH DESIGN AND METHODS: We conducted an active-comparator retrospective cohort study in the TriNetX US Collaborative Network across 72 healthcare organizations. Adults with body mass index (BMI) ≥30 kg/m2, repeated asthma documentation, and subsequent GLP-1-based therapy were compared with patients receiving active non-GLP pharmacologic weight-management therapy. After 1:1 propensity-score matching, 2,423 patients remained per cohort. Outcomes were assessed from day 1 through day 365 after the treatment-aligned index event. RESULTS: Recorded asthma exacerbation occurred in 1.7% versus 4.0% (risk difference [RD], -2.2%; 95% confidence interval (CI), -3.2% to -1.3%; risk ratio [RR], 0.438; 95% CI, 0.306-0.626). GLP-1-based therapy was also associated with lower systemic glucocorticoid exposure (16.4% vs 23.1%; RR, 0.712), emergency department/critical-care utilization (7.1% vs 13.0%; RR, 0.541), and acute respiratory failure (0.7% vs 1.8%; RR, 0.364). BMI- and glycated hemoglobin (HbA1c)-restricted sensitivity analyses were generally directionally concordant. GLP-1-specific adverse events were not systematically assessed. CONCLUSIONS: GLP-1-based therapy was associated with fewer recorded one-year respiratory and utilization events than active non-GLP pharmacotherapy. Residual confounding, treatment-persistence uncertainty, and exposure/outcome misclassification preclude causal inference.