Adverse childhood experiences (ACEs) affect autonomic cardiovascular regulation during orthostatic challenge in females but not males

Adverse childhood experiences (ACEs), defined as traumatic events that occur before the age of 18, are strongly associated with later cardiovascular disease (CVD), though more strongly among females compared to males. Biological sex differences in autonomic cardiovascular regulation have been well-documented. However, how ACEs affect autonomic cardiovascular regulation in females and males remains unclear. This study tested the hypothesis that ACEs affect autonomic cardiovascular regulation during head-up tilt (HUT; orthostatic challenge) in females and males. Forty-five (n=25 female; 23.1 ± 1.5 years (mean ± SD)) young adults from the Niagara Longitudinal Heart Study were analyzed. ACEs were assessed (Childhood Trust Event Survey 2.0) and participants were dichotomized into high (7-8 ACEs) and low (0-1 ACEs) exposure groups. Beat-by-beat mean arterial pressure (MAP; photoplethysmography) and heart rate (HR; electrocardiogram) were recorded during 10-mins of supine rest and 5-mins of 60° HUT. To examine whether ACEs affect autonomic cardiovascular regulation in females and males, the sample was stratified by sex and independent t-tests were conducted on the baseline, absolute, and rate of change in MAP and HR from supine baseline to hemodynamic stabilization during 60° HUT. At baseline, females with high ACEs exposure had a higher HR than females with low ACEs exposure (72 ± 12 vs. 62 ± 4 bpm, respectively; p = 0.002), but no difference in MAP (81 ± 12 vs. 79 ± 15 mmHg, respectively; p = 0.718). From supine to HUT, there was a larger increase in MAP in females with high ACEs exposure compared to females with low ACEs exposure (18 ± 7 vs. 6 ± 10 mmHg, respectively; p = 0.003). For HR, there was a smaller increase in females with high ACEs exposure compared to females with low ACEs exposure (7 ± 8 vs. 17 ± 11 bpm, respectively; p = 0.012). The rate of change in MAP from supine to HUT was faster in females with high ACEs exposure compared to females with low ACEs exposure (0.3 ± 0.2 vs. 0.1 ± 0.2 mmHg/s, respectively; p = 0.029). However, the rate of change in HR was slower in females with high ACEs compared to females with low ACEs (0.1 ± 0.1 vs. 0.2 ± 0.1 bpm/s, respectively; p = 0.031). In contrast, among males, there was no significant difference between high and low ACEs exposures for baseline HR (63 ± 14 vs. 59 ± 10 bpm, respectively; p = 0.514) or MAP (75 ± 11 vs. 83 ± 9 mmHg, respectively; p = 0.098). There were also no differences in males with high and low ACEs for changes in MAP (14 ± 7 vs. 11 ± 11 mmHg, respectively; p = 0.493) or HR (12 ± 13 vs. 10 ± 7 bpm, respectively; p = 0.788) from supine to HUT. As well, the rate of change in MAP and HR were similar in males with high and low ACEs exposure (rate of ΔMAP: 0.3 ± 0.3 vs. 0.2 ± 0.4 mmHg/s, respectively; p = 0.512 and rate of ΔHR: 0.1 ± 0.1 vs. 0.2 ± 0.2 bpm/s, respectively; p = 0.248). These data indicate that ACEs strongly affect autonomic cardiovascular regulation in females but not in males. Longitudinal studies are needed to determine whether these early changes in females are associated with increased risk of later CVD. This work was supported by the Canadian Institutes of Health Research (CIHR). This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.