Pulmonary Function, Walking Capacity, and Balance in Patients with Chronic Ischemic Stroke: A Cross-Sectional Study

Background: Respiratory dysfunction is common after stroke, but its relationship with chronic phase walking capacity and balance is unclear. We explored associations between spirometry and walking and balance performance. Methods: In this exploratory cross-sectional study, 27 outpatients with chronic ischemic stroke underwent spirometry, including peak expiratory flow (PEF); six-minute walk test (6MWT) and Berg Balance Scale (BBS) data were available for 25. We used Spearman correlations (Bonferroni α = 0.005), rank-based partial correlations, and linear regression. Results: PEF correlated with 6MWT distance (ρ = 0.568, 95% confidence interval [0.21, 0.82], p = 0.003; B = 23.92 m per L/s, R2 = 0.297). The association persisted after adjustment for age, body mass index, and time since stroke (partial r = 0.558, p = 0.007), although adjusted analyses did not meet the Bonferroni threshold. In 13 participants with high-quality spirometry, the correlation was similar in size but not significant (ρ = 0.360, p = 0.226). No other parameter correlated with 6MWT distance, and none with BBS scores. Conclusions: Higher PEF was associated with longer walking distance in this small exploratory sample, but effort-dependent measurement error and confounding by motor impairment cannot be excluded. PEF should not replace functional assessment; larger studies are needed.