Chest tightness as the sole presenting symptom of asthma is easy to dismiss — no wheeze, no cough, no classic alarm bells. Yet this atypical presentation may mask meaningful airway dysfunction, and identifying its physiological signature and risk profile in children carries real clinical weight for earlier, more accurate diagnosis.
This retrospective case-control study compared 39 children diagnosed with chest tightness variant asthma (CTVA) against 50 healthy controls. Fractional exhaled nitric oxide (FeNO) was significantly elevated in the CTVA group (p = 0.016), indicating active eosinophilic airway inflammation. Crucially, while total forced expiratory volume (FEV1) and forced vital capacity (FVC) appeared preserved, more sensitive small-airway flow metrics — including peak expiratory flow (PEF) and forced expiratory flows at 25%, 50%, and 75% of FVC (FEF25, FEF50, FEF75) — were all significantly reduced. Univariate analysis identified obesity, inhalant allergen sensitization, allergic rhinitis, atopic dermatitis, recurrent respiratory infections, and family history as associated risk factors for CTVA.
The finding that conventional spirometric ratios (FEV1/FVC) were abnormal while absolute FEV1 and FVC were not is consistent with early small-airway disease — a pattern increasingly recognized as underdiagnosed in atypical asthma phenotypes. FeNO elevation aligns with established biomarker thresholds for type-2 airway inflammation, reinforcing that CTVA shares a biologically plausible pathway with classic asthma despite its clinical distinctiveness. The robust atopic risk factor profile mirrors broader pediatric asthma epidemiology, but the CTVA-specific contribution of obesity is noteworthy given emerging evidence linking adipose-driven systemic inflammation to airway hyperresponsiveness. The study's limitations are significant: 39 cases precluded multivariable modeling, the retrospective design limits causal inference, and the single-center outpatient cohort may not generalize broadly. This is incremental but directionally valuable evidence — it argues for incorporating small-airway flow indices and FeNO measurement when evaluating children with unexplained chest tightness, rather than relying on normal FEV1 and FVC alone.