Long-term impact of COVID-19 on cardiac autonomic function and pulmonary function in hypertensive individuals: a cross-sectional study

Background Systemic arterial hypertension (SAH) may aggravate long-term cardiopulmonary consequences of COVID-19; however, persistent autonomic and pulmonary impairments after mild infection remain unclear. This study assessed the long-term impact of mild COVID-19 on cardiac autonomic function and pulmonary function in individuals with SAH. Methods This cross-sectional study included 52 adults with SAH allocated to 2 groups: those with SARS-CoV-2 infection 6–18 months earlier (G2+, n = 27) and those without (G1−, n = 25). Heart rate variability (HRV) was assessed by 24-hour Holter monitoring, pulmonary function by spirometry, and functional capacity by cardiopulmonary exercise testing (CPX). Linear and nonlinear HRV indices, spirometric variables, and CPX parameters were compared between groups, and correlations were examined between HRV, pulmonary function, and functional capacity. Results Pulmonary function was lower in G2+, with reduced forced expiratory volume in the first second (FEV 1 ) [2.3 (1.9, 2.6) vs. 2.5 (2.2, 3.0) L; P < .05] and Tiffeneau index [81.8 (77.5, 83.9) vs. 84.6 (80.8, 87.7); P < .05], and 30% of participants exhibited a restrictive pattern. No between-group differences were observed in cardiac autonomic control. Moderate correlations were found between peak oxygen uptake (V̇O 2 peak) and FEV 1 ( r = .50; P < .05) and between V̇O 2 peak and the 0 V% sympathetic marker ( r = − .55; P < .05) in G2+. Conclusions Mild COVID-19 was not associated with long-term alterations in cardiac autonomic control in hypertensive individuals. However, compared with hypertensive individuals without previous COVID-19, those with prior mild SARS-CoV-2 infection exhibited lower pulmonary function, predominantly characterized by a restrictive pattern, which was associated with reduced functional capacity.