A Biological Approach to Building Resilience and Wellness Capacity Among Police Exposed to Posttraumatic Stress Injuries: Protocol for a Randomized Controlled Trial

Background Law enforcement officers are routinely exposed to hazardous, disturbing events that can impose severe stress and long-term psychological trauma. As a result, police and other public safety personnel (PSP) are at increased risk of developing posttraumatic stress injuries (PTSIs) and disruptions to the autonomic nervous system (ANS). ANS functioning can be objectively and noninvasively measured by heart rate (HR), heart rate variability (HRV), and respiratory sinus arrhythmia (RSA). Traditional interventions aimed at building resilience among PSP have not adequately addressed the physiological ANS dysregulations that lead to mental and physical health conditions, as well as burnout and fatigue following potential psychological trauma. Objective In this study, we will investigate the efficacy of a web-based Autonomic Modulation Training (AMT) intervention on the following outcomes: (1) reducing self-reported symptoms of PTSI, (2) strengthening ANS physiological resilience and wellness capacity, and (3) exploring how sex and gender are related to baseline differences in psychological and biological PTSI symptoms and response to the AMT intervention. Methods The study is comprised of 2 phases. Phase 1 involves the development of the web-based AMT intervention, which includes 1 session of baseline survey measures, 6 weekly sessions that integrate HRV biofeedback (HRVBF) training with meta-cognitive skill practice, and 1 session of follow-up survey measures. Phase 2 will use a cluster randomized control design to test the effectiveness of AMT on the following prepost outcomes: (1) self-report symptoms of PTSI and other wellness measures; (2) physiological indicators of health and resilience including resting HR, HRV, and RSA; and (3) the influence of sex and gender on other outcomes. Participants will be recruited for an 8-week study across Canada in rolling cohorts. Results The study received grant funding in March 2020 and ethics approval in February 2021. Due to delays related to COVID-19, phase 1 was completed in December 2022, and phase 2 pilot testing began in February 2023. Cohorts of 10 participants in the experimental (AMT) and control (prepost assessment only) groups will continue until a total of 250 participants are tested. Data collection from all phases is expected to conclude in December 2025 but may be extended until the intended sample size is reached. Quantitative analyses of psychological and physiological data will be conducted in conjunction with expert coinvestigators. Conclusions There is an urgent need to provide police and PSP with effective training that improves physical and psychological functioning. Given that help-seeking for PTSI is reduced among these occupational groups, AMT is a promising intervention that can be completed in the privacy of one’s home. Importantly, AMT is a novel program that uniquely addresses the underlying physiological mechanisms that support resilience and wellness promotion and is tailored to the occupational demands of PSP. Trial Registration ClinicalTrials.gov NCT05521360; https://clinicaltrials.gov/ct2/show/NCT05521360 International Registered Report Identifier (IRRID) PRR1-10.2196/33492

On behalf of the Canadian Institutes of Health Research (CIHR) we are pleased to inform you that your recent application submitted to the Team Grant: Mental Wellness in Public Safety Team Grants -Funding Pool Police, entitled "Autonomic Modulation Training: A Biological Approach to Building Resilience and Wellness Capacity Among Police Exposed to Post-Traumatic Stress Injuries (PTSI)." has been approved for funding.
Documentation pertaining to the review of your application can be found through ResearchNet. Please note that your Authorization for Funding will follow electronically.
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Should you require additional information, please contact the CIHR Contact Centre at support-soutien@cihr-irsc.gc.ca. Please do not contact the officers or members of the peer review committee.
Congratulations on your success in this competition. This proposal aims to evaluate the efficacy of a web-based autonomic modulation training intervention (i.e., real-time biological heart-rate-variability biofeedback) to mitigate mental health symptoms of PTSI in police officers. The researchers contend that traditional interventions typically focus on cognitive, emotional, and behavioral aspects of PTGI and do not address neurological/physiological mechanisms such as autonomic nervous system regulation.
Overall, the application is well-written and the aims are well-developed and justified.
Below, this reviewer provides comments according to the evaluation criteria for this review.

Impact of the Research
The proposed research has the potential to provide new knowledge regarding the potential efficacy of a within-subjects autonomic modulation training intervention in police officers with PTGI. This approach is unique in its focus on "bottom up" autonomic dysregulation of PTGI instead of "top down" cognitive, emotional, and behavioral mechanisms that typify the focus of contemporary CBT approaches. The proposed aims are systematic and integrative, and follow established methods in the field.
The proposal integrates sex and gender, and will employ a gender-sensitive approach at all phases of the study. The research team provides a detailed background on sex and gender considerations related to their core measures of HRV and RSA, which provides a clear demonstration of their grasp of the importance of sex as a potential effect moderator.
The potential net result of the proposed research is a scalable intervention that targets autonomic nervous system dysregulation in police officers and related occupational groups with PTSI. Given issues of mental health stigma in this population, the proposed research, with its focus on a biological mechanism underlying PTSI, has the potential to be taken up more readily than interventions focused on "softer" mechanisms, such as emotions, cognition, and behaviors. Further, this intervention can be deployed as a primary or adjunctive treatment by mental health clinicians working with police officers and other occupational groups affected by PTSI.
The research team has established relationships with several police forces across Canada, which is a notable strength of the proposed study. If found to be effective, their proposed intervention has the potential to be disseminated quite broadly, thus helping to mitigating symptoms of PTSI and bolster resilience and wellness in the broader population of police officers in Canada.

Approach
Assessment/Évaluation: The proposed design of the study is appropriate and will employ state-of-the-art methods to evaluate study aims. The literature review is complete and up-to-date, and demonstrates the team's in-depth understanding of the broader scientific literature on the role of autonomic nervous system dysregulation in PTGI, and biofeedback intervention approaches that may help mitigate this dysregulation. The roles and responsibilities of the Sex and Gender Champion identified adhere to the best practices outlined by the Institute of Gender and Health. The research team clearly articulated the limitations of their proposed study, as well as approaches to address them, most notably to address issues related to mental health stigma, which is among the most salient challenges to working with mental health issues in correctional workers.
The most notable limitation of the proposed study is the lack of an active control (or even a TAU or wait-list control) condition, which will ultimately make it impossible to determine the relative efficacy of the proposed intervention. Given the large-scale nature of the proposed study, the research team may consider potentially including such a condition, which would provide a more rigorous test of the efficacy of this intervention approach in treating PTSI.
Another potential limitation is the extent to which the police officers who will be recruited into the study are representative of the broader population of police officers. Given issues of mental health stigma, do the researchers anticipate recruiting a healthier/sicker sample? How might this impact generalizability of results? What measures are in place to ensure broader generalizability of study results? Related to this point, do the inclusion/exclusion criteria allow for recruitment of a sample that is representative of the target population?
Given the potential for police officers to be exposed to traumatic and stressful events as part of their work, what procedures are in place to assess these exposures over the course of the study, most notably between pre-and postassessments, which may influence autonomic measures and mental health symptoms?
Has the research team considered the potential effects of sleep, recreational drug use, and medical conditions (e.g., cardiovascular disease) on study outcomes?
Minor comment: How will participation in other treatment(s), most notably those affecting autonomic nervous system function (e.g., beta blockers), be monitored and managed in the research strategy/data analysis?
It is unclear why analyses will be stratified by sex/gender. Why not incorporate sex/gender as a potential main effect and moderating variable?
The research team does not describe any anticipated difficulties and how they plan to address them.
Budget is appropriate and justified in relation to the proposed activities. Assessment/Évaluation:

Originality of the Proposal
The proposed study is unique in its focus on autonomic nervous system dysregulation instead of a more traditional focus on cognitions, emotions, and behaviors related to PTSI. The proposal articulates a systematic approach to developing and testing the AMT intervention. The use of wearable technology, real-time app-based visualized biofeedback tailored to individuals' unique biorhythms is also novel. The research team is also sensitive to populationspecific needs of police officers, as well as issues of mental health stigma in this occupational group. They have also established relationships with several police forces across Canada, which will help increase generalizability of study results. Of note, the proposed study will also provide new insight into the role of sex/gender as autonomic markers of PTSI and resilience, which has been largely ignored in this literature.

Applicant(s)
The research team has a long track record of excellence in the proposed area. The team exemplifies a team grant by including experts covering all of the relevant areas for this multidisciplinary project. There is clear complementarity of expertise and synergistic potential to carry out the proposed aims. The team is productive in their research area and have made numerous contributions on AMT and related topics to the scientific literature.

Open Science and Knowledge Translation Plan
The researchers outline a detailed knowledge translation, open science, and data management plan that embraces open science principles and practices over the duration of the proposed study. Of note, the research team's relationships with police services should help with recruitment efforts and if found to be efficacious, to more broadly disseminate the intervention to help improve mental health symptoms in the broader community of police officers in Canada.
What is somewhat unclear, however, is the availability of the intervention will be made known to the broader how community of police officers. And how can police officers trust the intervention such that their sensitive mental health data will not be shared with others, most notably their employer? 1.

Impact of Research
Dr. Anderson et al's research proposal has significant potential to enhance our understanding of sex and gender differences in the body's objective physiological response to acute and cumulative stress and trauma exposure. Wearable technology to measure real-time biofeedback for first responders will enhance an individual's self awareness of their ANS reflexes, using a convenient method that is realistic to implement and easy to grasp within stoic workplace cultures. If successfully adopted by test subjects, the indirect impact of this study could lead to significant interest and buy-in from the colleagues of test subjects given the tight-knit culture of many PSP workplaces.

Approach
The approach of using HRVB technology to increase self-awareness of the individual stress response represents an exciting new addition to conventional talk therapy approaches to addressing acute and chronic stress reactions. This approach as outlined by Dr. Anderson et al.'s research proposal is a welcome addition to conventional (ie talk therapy) approaches as noted by this quote " research and clinical practice have shown that directing patients to apply effortful, consciously deployed strategies like reappraisal are not helpful when either subcortical circuitry (e.g., brainstem) or peripheral (e.g., nervous system) physiology is Upstream prevention with a focus on health, wellness and resiliency is an important tone to dysregulated." countering mental health stigma in the PSP workplace.
Web-based delivery of an online platform intended for psychoeducational training for police officers requires a high level of motivation and engagement by frontline staff. Buy-in to actively engage and complete this style of training may be a limitation of this study's approach.

Originality of the Proposal
Addressing the physiological underpinnings of the stress response utilizing wearable technology for frontline first responders is a new chapter in assisting police officers in understanding and potentially rewiring ANS reflexes. The proposal also recognizes the most current findings on existing limitations to current resiliency programs for preventing and treating PSP PTSI's.

Track record
Navigating the complexities of a large public safety organization is no easy task and Dr. Anderson's proven track record as demonstrated in her biography, will enhance buy-in from various levels, most notably, the Overall, the movement beyond a disorder-based approach and towards one that normalizes the acquisition of stress injuries is a novel contribution. This research method and tone is consistent with various provincial (notably BC and Saskatchewan's) anti-stigma awareness campaigns and will be a significant contribution to open science upon published findings.

Criterion #1: Research Approach This application was well laid out, easy to understand, with clear goals and objectives. However, it was not apparent, the intended application of the online AMT post-study. Included in the application was an educational component that physical and psychological factors do not happen independently of each other. There was a good explanation of the psychophysiological process of how the Sympathetic Nervous System (SNS) and Parasympathetic Nervous System (PNS) are interconnected to the physical body. The visual aids and the figures that included explanations of the various measurements and questionnaires were very helpful. This proposal took great care in explaining Heart Rate Variability Biofeedback (HRVB), and why it is needed and how it is applied to this research. The bottom up
approach was refreshing, however, there is concern that it is only individual focused.
Careful consideration was given to knowledge transfer including publications, partnerships, face to face meetings, although it appears there is room to reach a broader audience, such as, conference presentations etc.
Research supports that AMT in clinical and non-clinical setting are effective, hence, I am a little confused for the need of this study to be so robust. It is understood that it specifically addresses police officers and it will address the sex and gender to baseline biological differences in PTSI symptoms and the effectiveness of AMT intervention, however, I am unsure if the requested funding amount is fiscally responsible with the anticipated outcome(s).
In addition to the AMT, the proposal also intends to integrate psychoeducational modules focused on developing meta-cognitive skills. In addition, participants will receive further training on effective coping skills and emotional regulation. I do not understand how it will be separated in the postmeasure analysis, as to whether the AMT solely affected the outcome of lowering PTSI symptoms and increased their resilience and wellness capacity or if these other additional online modules and training also had an affect on the post measurements. The proposal states that the "reduction of PTSI symptoms and improvement in resilience are uniquely accounted for by the AMT intervention", but what does this mean? For example, is it taken into account additional "treatments" (medicinal or nonmedicinal) while participating in the study?
The proposal indicates that self regulation by conditioning the HRV and RSA with the proposed online AMT has short-term and long-term benefits, however, the post measurements stops after the 6 weeks of implementing the AMT. This would only indicate the immediate outcome and will not measure any long-term benefits as indicated. Are the benefits of AMT only short-term while being Having said that, having access to an AMT easily accessible (especially for rural and remote PSPs), having autonomy and easy to use would be welcomed, but again, in my experience, it would not be utilized as much as one would hope in the "real world". Understanding why this is, how to improve 'buy-in" and understanding the challenges would be important, therefore, digging deeper into engagement and adherence would be recommended.
Highlighted was a knowledge gap in current research of how sex and gender may affect receptivity and treatment effects of HRVB. It is also worthy to note the originality looking in depth the organizational and occupational stresses taken into consideration, specifically for female officers. It is also welcomed to see the flexibility and effort put into the analysis to prominent emerging themes.
Criterion #3: Applicant(s) There appears to be a concerted effort to form a multi-disciplinary team with a wide range of expertise and some activities that garnished user-informed insights. Although it wasn't immediately apparent, it was found in the budget proposal there is intentions to utilize Postdoctoral fellows, graduate and summer students.
As a knowledge-user peer reviewer, it is difficult to comment beyond the above observations. Criterion #4: Environment for the Research I think there is a good plan laid out to advertise for recruitment, however, I am concerned of the small margin that is accounted for with attrition. Given the workload demand, unpredictable nature of the work, shift work, I think it will be a challenge recruiting police officers that can commit to the study and maintaining high attrition. For example, committing to 1 hour each week at the same time each time, will be difficult, and this is only one of the many commitments required for the study. I think this attrition is going to be more of an issue than is accounted for in the study. Having said that, there is a small financial incentive that may assist with follow through.
I do like the forethought into those PSPs that self-assess as severe and on the high end of the cut off career ending and/or limiting, possible machoism. Their PTSD PSPs may not disclose until there is such a significant deviation of baseline behavior that draws attention to themselves, thus, surmising that they are on the moderate-severe spectrum of PTSD and its related symptomatology. Again, I pose the question: given the heightened state of the PSP with symptomatology, how many would embark in an AMT on their own and what are the challenges associated with it?
5. It is also concerning the application after the study may be too expensive for PSP to utilize. Will PSPs be able to afford the hardware needed (ie/ Fitbit, Apple iWatch) and the software costs , if it is not covered with health benefits? This can be very costly.

Summary:
This application does a great job of explaining the psychophysiological and the biomechanics of HRV. Previous research has indicated that physiological functioning has shown success in building resilience and wellness capacity, however, there is concern of how realistic this would be in the "real world" with PSP engagement and adherence to an online AMT. This is not to say that the AMT would not be beneficial, however, it would only be beneficial if it is being utilized. Additionally, it is concerning that this study may have some duplication, it is individual-focused and is not expected to have high impact.