Heart Rate Variability as a Marker of Distress and Recovery: The Effect of Brief Supportive Expressive Group Therapy With Mindfulness in Cancer Patients.

These results suggest the effectiveness of this modified group-based program for distress reduction and also provide preliminary evidence for the use of HRV as a biomarker of distress and recovery. HF power from HRV variables may serve as a quantitative biomarker of the treatment response of distress management, including anger.