Marc N. Jarczok

The bio‐psycho‐social model highlights intra‐individual and inter‐individual interactions, including psychotherapy. The processing of these interactions within a person takes place, among others, in the central autonomic network (CAN). The CAN's autonomic output to the periphery can be indexed by heart rate variability (HRV), representing individual adaptive capacity. Further, the CAN influences the hypothalamus‐pituitary–adrenal axis with its product cortisol. The aim consisted in investigating HRV and cortisol as well as their relation to symptom course in response to short‐term psychotherapy. A single‐arm, uncontrolled, explorative study was conducted at an outpatient psychotherapeutic consultation in the workplace offered to employees with mental or psychosomatic complaints. Questionnaires included symptoms of depression, irritation and functional impairment. Circadian profile of HRV and salivary cortisol concentrations collected pre and post short‐term psychotherapeutic intervention (4–12 sessions) were assessed. Multilevel‐linear mixed regressions were calculated. Out of 29 participants (mean age 42; 72% female), 24% were on sick leave from work. Cortisol concentrations were neither affected by intervention nor by symptom course. The proportion of individuals showing a vagally mediated HRV in the range of the lowest quartile assessed for age‐ and sex‐matched healthy controls was reduced at follow‐up (pre 34%, post 22%; p = .017). Higher vagally mediated HRV at baseline predicted lower symptom burden at follow‐up. Thus, the results support the assumption that HRV reflects the capability of an organism to adapt and recover. Patients with reduced HRV might need additional psychotherapeutic sessions to achieve the same symptom improvements than patients with retained HRV.