An Investigation of the Physiological Effects of Animal-Assisted Therapy on Stress and Well-Being in End-Stage Cancer Patients: Examination of Brain Hormone Promotion

Hiroko Fujisawa¹* and Takayuki Kumasaka²

¹Department of Nursing, Faculty of Health Sciences, Nihon Institute of Medical Science, Japan
²Department of Nursing, School of Health Sciences, Tokoha University, Japan

*Corresponding Author: Hiroko Fujisawa, Department of Nursing, Faculty of Health Sciences, Nihon Institute of Medical Science, Japan.

Received: September 01, 2025; Published: October 31, 2025

Abstract

The present study investigated the physiological effects of animal-assisted therapy (AAT) on stress reduction and well-being of terminal cancer patients, focusing on the autonomic nervous system activity and brain hormone promotion. With the global increase in cancer incidence and mortality, especially among the elderly, palliative care with emphasis on the patients’ quality of life (QOL) is essential. AAT, involving trained therapy dogs, reportedly promotes relaxation, reduces stress, and improves mental health, but objective evidence in terminal patients remains limited.

In this cross-sectional study conducted at a hospice from April 2022 to February 2023, 35 terminal cancer patients who liked dogs participated. A heart rate variability (HRV) analysis was performed to assess the autonomic nervous system changes, measuring the low frequency (LF)/high frequency (HF) ratio and HFnu as indicators of sympathetic and parasympathetic activities, respectively. Salivary cortisol levels, a stress marker, and subjective measures, including visual analog scale (VAS) scores, were also recorded before and after the 10-minute AAT sessions. The therapy involved interaction with trained therapy dogs, with the patients freely engaging through touching, talking, or simply being near the animals.

Our results showed significant decreases in the LF/HF ratio and salivary cortisol levels, alongside increases in HFnu, indicating enhanced parasympathetic activity and relaxation. Subjectively, patients reported reduced stress and improved mood post-AAT. These findings suggest that AAT stimulates the release of happiness-related neuropeptides, including endorphins and oxytocin, which contribute to stress alleviation and emotional well-being. The activation of the reward pathways and reduction of stress hormones support the physiological basis for AAT’s benefits in terminal care.

In conclusion, dog-assisted therapy effectively promotes relaxation and reduces stress in terminal cancer patients by modulating autonomic function and neurohormone secretion. Repeated animal interactions may sustain these benefits, improving the patients’ QOL during end-of-life care. Further research with larger samples and control groups is needed to confirm its long-term effects and optimize the therapeutic protocols.

 Keywords: Alternative Therapy; Palliative Care; End of Life; Cancer Patients; Animal Assisted Therapy

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Citation

Citation: Hiroko Fujisawa and Takayuki Kumasaka. “An Investigation of the Physiological Effects of Animal-Assisted Therapy on Stress and Well-Being in End-Stage Cancer Patients: Examination of Brain Hormone Promotion”.Acta Scientific Medical Sciences 9.11 (2025): 89-98.

Copyright

Copyright: © 2025 Hiroko Fujisawa and Takayuki Kumasaka. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.