Effect of handholding on heart rate variability in both patients with cancer and their family caregivers: a randomized crossover study

Sakuma et al. BioPsychoSocial Medicine (2021) 15:14 https://doi.org/10.1186/s13030-021-00217-y RESEARCH Open Access Effect of handholding on heart rate variability in both patients with cancer and their family caregivers: a randomized crossover study Hiroko Sakuma, Hideaki Hasuo* and Mikihiko Fukunaga Abstract Background: Many family caregivers of patients with cancer feel guilty about self-care. A meaningful relationship with patients reduces such negative feelings and functions as self-care for family caregivers. Moreover, handholding improves autonomic functions in non-cancer patients. However, the effects of handholding on both patients with cancer and family caregivers remain unknown. Methods: We evaluated the effects of handholding on heart rate variability (HRV) in patients with cancer and their family caregivers. This randomized crossover study divided patients with cancer and their family caregivers into two trial groups: Handholding trial (the family caregiver holds the patient’s hand for five minutes) and Beside trial (the family caregiver stays beside the patient without holding their hand). The study included 37 pairs of patients with cancer who received treatment in the cancer department of a university hospital in Japan and their family caregivers (n = 74). The primary end-point was the change in HRV before and during the intervention. Results: The median performance status of the patients was 3. An interaction was observed between trials in the standard deviation of the normal-to-normal interval (SDNN) of HRV for family caregivers (F = 7.669; p = 0.006), and a significant difference in time course was observed between the trials (before p = 0.351; during p = 0.003). No interaction was observed between trials in the SDNN for patients (F = 0.331; p = 0.566). Only a main effect in time course (F = 6.254; p = 0.014) was observed. SDNN increased significantly during the intervention in both trials (Handholding trial: p = 0.002, Beside trial: p = 0.049). Conclusions: Handholding improves autonomic functions of family caregivers and may function as self-care for family caregivers. Trial registration: UMIN000020557. Registered on January 15, 2016. Keywords: Handholding, Family caregivers, Heart rate variability, Self-care, Autonomic functions * Correspondence: Department of Psychosomatic Medicine, Kansai Medical University, Shinmachi 2-5-1, Osaka 573-1090 Hirakata, Japan © The Author(s). 2021 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Sakuma et al. BioPsychoSocial Medicine (2021) 15:14 Background Family caregivers are less motivated to engage in selfcare because they feel guilty about not effectively being involved in patient care or of taking care of themselves [1]. For example, in a study that introduced mindfulness-based stress reduction to family caregivers of lung cancer patients, the family caregivers prioritized the patients’ well-being, and their distress was not reduced [2]. Family caregivers who do not spend time engaging in self-care because of their sense of responsibility for patient care feel a greater burden [3], which results in unsuccessful psychological and emotional management for themselves [4]. Previous literature has suggested that there is an association between a heavy patient care burden and an increased mortality rate for family caregivers [5]. The importance of self-care support for both family caregivers and patients with cancer has been recognized [6]. There are two types of self-care support. One type is direct intervention, which directly introduces self-care techniques such as relaxation. Several studies have reported that educating family caregivers about the benefits of relaxation is effective in improving their self-care practice [7, 8]. The other type is indirect intervention, which provides skill training for family caregivers to become better involved in patient care [9]. Moreover, effective interaction with patients has been reported as a form of self-care for family caregivers [1]. A family caregiver holding a patient’s hand is one of the most common actions in daily life. Many previous studies suggest the usefulness of touching or massage as complementary and alternative forms of medicine [10, 11]. However, to our knowledge, only two studies have evaluated the effectiveness of handholding by family caregivers. One study evaluated the effects of handholding by family caregivers on gastric motor function using extracorporeal ultrasound in patients with cognitive impairment [12]. The other study evaluated the gastric motor function of patients with decreased levels of consciousness using extracorporeal ultrasound while family caregivers were holding their hand in a relaxed state [13]. In both studies, the patients’ gastric motor function and autonomic function were significantly increased during handholding. However, the previous studies were limited by the high invasiveness of the gastric motor function measurement with extracorporeal ultrasound and the lack of evaluation of autonomic function in family caregivers. A study using a less invasive procedure for measuring autonomic function and evaluating the effects on both patients and family caregivers is necessary. Heart rate variability (HRV) is an indicator of autonomic function that can be measured less invasively and simultaneously in both patients and family caregivers. Page 2 of 7 This study aimed to evaluate the effect of family caregivers holding the hands of their family members with incurable cancer (patient) by measuring the HRV of both caregivers and patients. We hypothesized that handholding serves as a direct intervention for family caregivers’ self-care support by improving the HRV of family caregivers and as an indirect intervention by improving the HRV of patients. Methods Study participants In this study, we defined family caregivers as family members who directly provided care to a relative with cancer including spouses; patients were defin (...truncated)