Autonomic Nervous System Response to Psychosocial Stress in Anorexia Nervosa: A Cross-Sectional and Controlled Study

Ileana Schmalbach; Benedict Herhaus; Sebastian Pässler; Sarah Runst; Hendrik Berth; Silvia Wolff; Bjarne Schmalbach; Katja Petrowski

doi:10.3389/fpsyg.2021.649848

Autonomic Nervous System Response to Psychosocial Stress in Anorexia Nervosa: A Cross-Sectional and Controlled Study

Front Psychol. 2021 Mar 17:12:649848. doi: 10.3389/fpsyg.2021.649848. eCollection 2021.

Authors

Ileana Schmalbach^{1

2}, Benedict Herhaus¹, Sebastian Pässler³, Sarah Runst³, Hendrik Berth², Silvia Wolff³, Bjarne Schmalbach¹, Katja Petrowski^{1

4}

Affiliations

¹ Department of Medical Psychology and Medical Sociology, University Medical Center of the Johannes-Gutenberg University Mainz, Mainz, Germany.
² Division of Psychological and Social Medicine and Developmental Neurosciences, Research Group Applied Medical Psychology and Medical Sociology, Carl Gustav Carus Faculty of Medicine, Technische Universität Dresden, Dresden, Germany.
³ Department of Psychotherapy and Psychosomatic Medicine, University Hospital Carl Gustav Carus Dresden, Dresden, Germany.
⁴ Abteilung für Innere Medizin III, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden, Dresden, Germany.

Abstract

To foster understanding in the psychopathology of patients with anorexia nervosa (P_AN) at the psychological and physiological level, standardized experimental studies on reliable biomarkers are needed, especially due to the lack of disorder-specific samples. To this end, the autonomic nervous system (ANS) response to a psychosocial stressor was investigated in n = 19 P_AN (BMI: 18.7 ± 3.3 kg/m²), age, and gender-matched to n = 19 healthy controls (HC; BMI: 24.23 ± 3.0 kg/m²). For this purpose, heart rate (HR) and heart rate variability (HRV) parameters were assessed in a cross-sectional study design under two experimental conditions: (1) rest and (2) stress (Trier Social Stress Test). In addition, psychological indicators of stress were assessed. An 2 × 2 × 8 ANOVA demonstrated similar HR and HRV patterns (except LF-HRV) between P_AN and HC at rest. Under stress, P_AN (vs. HC) demonstrated a blunted HR [condition^*time^*group: F _{(2.91, 104.98)} = 9.326, p = 0.000, η² = 0.206] and an attenuated HRV response (reduced SNS/PNS reactivity). Significant effects of stress appraisal (SA) and BMI on HRV-reactivity were revealed. SA on SDNN = Condition^*time^*SA = F _{(4.12, 140.15)} = 2.676, p = 0.033, η² = 0.073. BMI on LF/HF-Ratio = Condition^*time^*BMI = F _{(3.53, 60.16)} = 3.339, p = 0.019, η² = 0.164. Psychological indices suggested higher levels of chronic and appraised stress in P_AN relative to HC. Additional analyses demonstrated that ED-symptoms are highly correlated with the latter constructs, as well as with psychological burden, but not with weight. Further, it was shown that abnormalities in reactivity persisted despite normalized ANS activity. Overall, we suggested that besides weight recovery, improvement in stress appraisal could be beneficial for cardiac health. In this light, a combination of therapy (e.g., development and activation of coping skills, cognitive reappraisal) and biofeedback training may improve treatment outcomes and regulate stress reactivity.

Keywords: HRV in AN; anorexia nervosa; eating disorders; heart rate variability; laboratory stress induction; trier social stress test.