Even before COVID-19, the healthcare workforce reported substantial burnout and mental health concerns (Mousavi et al., 2017; Shanafelt et al., 2012). Worse patient safety outcomes are one notable consequence of healthcare worker burnout (Cimiotti et al., 2012; Hall et al., 2016). Multiple empirical studies conducted during COVID-19 revealed that the pandemic severely intensified distress and burnout among healthcare workers (Barello et al., 2020; Sultana et al., 2020; Vizheh et al., 2020). Compared to their non-nursing healthcare counterparts, nurses were particularly prone to suffering from the psychological impact of the COVID-19 pandemic (Batra et al., 2020; Lai et al., 2020).
The nurse’s role as “care provider” is so central to the mental and physical health and well-being of others, we often fail to acknowledge the ways in which nurses tend to neglect their own self-care needs (Mullen, 2015, 2015). In fact, Logan and colleagues (2023) recently found work stress to be an important negative predictor of self-care among nurses. Most nurses report that the opportunity for breaks during the workday is very rare (Linton & Koonmen, 2020; Ross et al., 2019), making it difficult to engage in an important aspect of self-care—nourishing the body using attuned eating (Hotchkiss, 2018; Nahm et al., 2012). Consistent with these findings, several studies found healthcare professionals, and nurses in particular, to be at high-risk for disordered eating, especially when job-related stressors were high (King & Arthur, 2004; Marko et al., 2022; Nicholls et al., 2017). In fact, one study reported that nearly two-thirds of a sample of nurses (N=378) had significantly elevated scores on dietary restraint, emotional eating, and eating through external as opposed to internal cues (Wong et al., 2010).
Amidst COVID-19-related stressors such as staff shortages, overflowing intensive care units, and lack of adequate personal protective equipment (Emanuel et al., 2020; Livingston et al., 2020; Theorell, 2020), it became critical to study interventions to aid healthcare workers in coping with pandemic circumstances in effort to maximize resilience and prevent further exacerbation of burnout. A Cochrane review of interventions to improve the mental health and resilience of frontline healthcare workers during pandemics of the past two decades found no ‘high confidence’ interventions, underscoring a need for more research on this matter (Pollock et al., 2020).
To better understand predictors of resilience and well-being, multiple researchers have turned to examine ‘sense of coherence’ as a relevant construct during COVID-19 (Ruiz-Frutos et al., 2021; Szovák et al., 2020). Sense of coherence is defined as the capacity to see one’s life as meaningful, comprehensible, and manageable (Antonovsky, 1987); and it was developed as part of Antonovsky’s theory of ‘salutogenesis’ (Antonovsky, 1996)—i.e., the origins of health—or inquiry into the processes that enable one to stay well. Colomer-Pérez and colleagues (2022) used a salutogenic model of health in a sample of 921 students training to be nursing assistants and found sense of coherence to be positively associated with agency to engage in self-care. Decades of research demonstrating a robust relationship between sense of coherence, lower traumatic stress, and multiples markers of well-being, including burnout and job satisfaction among nurses (Eriksson & Lindström, 2006; Masanotti et al., 2020; Schäfer et al., 2019), creates a solid foundation from which to build a strengths-based, salutogenic intervention to promote health, especially warranted during times of acute distress like the COVID-19 pandemic (Schäfer et al., 2020).
A related psychophysiological model of resilience that has also been well-studied as a factor connected to psychosocial well-being, self-regulation, and autonomic nervous system functioning is known as cardiac coherence (McCraty & Zayas, 2014) or resonant frequency (Sevoz-Couche & Laborde, 2022). Resonant frequency is a temporal coherence between heart rate and breathing that could be understood as the physiological counterpart to Antonovsky’s psychological construct. The system underlying this physiological coherence, also known as resonance, is dynamic and based on complex neuro-cardiac communication pathways (Lehrer, 2013; Shaffer et al., 2014). In brief, resonance is something achieved when there is a harmonious and efficient synchronization between our physiological systems that allows for optimal modulation of emotional states, functional performance, and overall health (Bradley et al., 2010; McCraty & Zayas, 2014; Segerstrom & Nes, 2007). We measure resonance by examining the change and pattern in the beat-to-beat rhythm of the heart; the more the rhythm appears like a smooth sine wave, the more resonance or coherence one has (Sevoz-Couche & Laborde, 2022; Shaffer et al., 2014). These beat-to-beat changes in rhythm are known as heart rate variability (HRV), and for decades researchers have studied how they are associated with physical and emotional states (Lee et al., 2023; Thayer et al., 2009; Zhu et al., 2019).
Higher HRV is a predictor of health and longevity (Piccirillo et al., 2001; Ponikowski et al., 1997; Zulfiqar et al., 2010) and has even been used to detect COVID-19 cases among healthcare workers in the early part of the pandemic (Hasty et al., 2021). HRV biofeedback (HRVB) is a technique that uses audio and/or visual cues derived via signals generated from blood flow detected in the body to train people to become more attuned to the interplay of physiological markers such as the breath and heartbeat (Lehrer & Gevirtz, 2014). This mind-body connection supports people in achieving optimal HRV levels and has been found in meta-analyses to help with a wide variety of stress-related concerns, including anxiety, traumatic stress, anger, depression, athletic and artistic performance, chronic pain, and sleep problems (Goessl et al., 2017; Lehrer et al., 2020). In fact, Buchanan and Reilly (2019) successfully used HRVB to reduce distress in healthcare professionals.
While many have focused on the physiological mechanisms through which HRVB yields health benefits (Lehrer, 2013; Lehrer & Gevirtz, 2014; McCraty & Shaffer, 2015), a recent review of the literature suggests the positive effects of HRVB on emotions may occur by improving interoceptive sensibility (Pinna & Edwards, 2020). Interoceptive sensibility, better known as interoception, is defined as our conscious capacity to integrate and adaptively respond to body-related signals such as hunger, thirst, temperature, and pain; it is a crucial survival mechanism for maintaining homeostasis (Craig, 2002). Deficits in interoception are well known to be evident in individuals with mental health concerns, especially those with eating disorders (Füstös et al., 2013; Löffler et al., 2018; Martin et al., 2019). In fact, using HRVB for disordered eating has become a promising area of research warranting more attention (Godfrey et al., 2019; Meule et al., 2012; Scolnick et al., 2014).
Study Aims
Given the importance of enhancing healthcare worker well-being, the purpose of the present study is to report the acceptability, usability, and early signals of efficacy for HRVB with a commercially available smartphone app in healthcare professionals reporting elevated eating distress during the first year of the pandemic. Specifically, this mixed methods pilot feasibility trial primarily aimed to test study enrollment, intervention retention, engagement, acceptability and usability. Qualitative and quantitative data will be integrated to answer usability and intervention acceptability. The secondary aim involved testing preliminary efficacy through examining changes in disordered eating, perceived stress, resilience, interoceptive sensibility, and mindful self-care over the course of the intervention. In sum, the goal of the current study was to evaluate data gathered in preparation for developing a future definitive trial utilizing a mindfulness-based HRVB smartphone app in a mind-body intervention for eating distress.