Abstract / Summary
Abstract Background Electronic cigarettes (e-cigarettes) are widely promoted as safer alternatives to combustible tobacco, yet growing evidence suggests that they may induce early respiratory dysfunction, particularly among young adults. Objective clinical and radiological assessments of exclusive e-cigarette users in low- and middle-income countries remain limited. Objective To evaluate respiratory symptoms, pulmonary function, functional exercise capacity, and high-resolution computed tomography (HRCT) abnormalities among exclusive e-cigarette users, and to examine whether risk perception aligns with measurable health outcomes. Methods In this analytic cross-sectional study, 104 young adults were enrolled (52 exclusive e-cigarette users and 52 non-smoking control group). All participants underwent clinical evaluation, spirometry (FEV₁, FVC, FEV₁/FVC, MEF₂₅–₇₅), six-minute walk test (6MWT), pulse oximetry, Borg dyspnoea scoring, and low-dose HRCT. Perception scores were assessed using a validated questionnaire. Between-group comparisons and multivariable regression analyses were performed. Results E-cigarette users exhibited a markedly higher symptom burden, including dyspnea, cough, wheeze, and prior respiratory infections (all p < 0.001). Functional capacity was significantly impaired, with reduced 6MWT distance (484.35 ± 117.20 versus 557.38 ± 94.58 m; p < 0.001) and greater exertional desaturation (p < 0.001). Spirometric parameters did not differ significantly between groups, although e-cigarette users showed numerically lower values across the assessed indices. HRCT abnormalities—including air trapping (30.8% vs 3.8%) and reticulation (26.9% vs 3.8%)—were observed in e-cigarette users versus controls (p < 0.001), moderate-to-severe radiological involvement occurred exclusively in this group. Higher cumulative exposure correlated with worse spirometric, functional, and radiological outcomes. Perception scores did not differ between groups ( p = 0.67). Conclusion Exclusive e-cigarette use among young adults was associated with increased respiratory symptom burden, reduced exercise capacity, and structural abnormalities on HRCT, despite the absence of significant between-group differences in conventional spirometric parameters. These findings challenge the perception of e-cigarettes as harmless alternatives and underscore the need for early detection and regulatory action. Trial registration ClinicalTrials.gov identifier NCT07422415s.