Autonomic nervous system dysregulation in response to postural change in patients with pectus excavatum in Taiwan: a pilot study

Background: Pectus excavatum (PE) negatively impacts psychological function, but its effect on autonomic nervous system (ANS) function has not been investigated. We evaluated ANS function following postural changes in patients with PE. Methods: The participants were 14 healthy men (control group) and 20 men with PE (study group). Psychological function was assessed using the visual analog scale for pain, Brief Symptom Rating Scale-5, and Beck Depression Inventory-II. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). ANS regulation in response to postural change was measured in the supine position and immediately after sitting. All measurements were compared between the control and study groups at baseline and between the study groups before and after Nuss surgery. Results: At baseline, upon postural change, symptomatic activity increased in the control group (50.3-67.4%, p= 0.035) but not in the study group (55.0-54.9%, p= 0.654); parasympathetic activity decreased in the control group (49.7-32.6%, p= 0.035) but not in the study group (45.1-45.1%, p = 0.654); and overall ANS regulation increased in the control group (1.02-2.08, p=0.030) but not in the study group (1.22-1.22, p= 0.322). In response to postural change after Nuss surgery in the study group, sympathetic activity increased (48.7-70.2%, p = 0.005), parasympathetic activity decreased (51.3-29.8%, p= 0.005), and overall ANS regulation increased (0.95-2.36, p= 0.012). Conclusion: ANS function in response to postural change is dysregulated in patients with PE, which improved after Nuss surgery.