A Systematic Review on Exploring the Role of MicroRNAs as Diagnostic and Prognostic Biomarkers in Elderly-Onset Asthma

MicroRNAs (miRNAs) are small, non-coding RNA molecules that function as significant post-transcriptional regulators of gene expression, influencing a wide range of biological processes, including immune modulation, inflammation, and cellular remodeling. Their dysregulation has been implicated in diverse chronic diseases, including asthma. Elderly-onset asthma (EOA) presents substantial clinical challenges due to its distinct immunopathophysiology, heterogeneous phenotypic presentations, and differential response to standard therapies. Emerging evidence underscores the integral role of miRNAs in asthma pathogenesis, modulating inflammatory cascades, immune dysregulation, and airway remodeling. This systematic review explores the significance of miRNAs as diagnostic and prognostic biomarkers in EOA, emphasizing their differential expression profiles and involvement in disease progression. Key regulatory miRNAs, including miR-21, miR-155, miR-140-3p, and miR-221, modulate molecular pathways implicated in Th2-driven inflammation, epithelial-to-mesenchymal transition, and immune homeostasis. Dysregulated expression of miRNAs correlates with disease severity, therapeutic responsiveness, and long-term pulmonary outcomes, highlighting their clinical relevance in precision medicine. However, the translational applicability of miRNA-based biomarkers is constrained by methodological inconsistencies in miRNA profiling, including sample variability and the need for standardized protocols. Despite these challenges, the non-invasive nature and diseasespecific expression patterns of miRNAs present a compelling case for their integration into biomarker-driven diagnostics and personalized treatment strategies. Future research should prioritize the validation of miRNA markers in diverse cohorts and explore their functional implications in EOA. By developing the regulatory networks governed by miRNAs, this review sets the stage for molecular asthma diagnostics and therapeutics, underscoring the potential of miRNA-targeted interventions in optimizing disease management and clinical outcomes in elderly populations.