Biofeedback-Enhanced Cognitive–Behavioral Therapy Delivered Virtually to Youth With Inflammatory Bowel Disease: A Randomized Controlled Trial

Abstract

Background

Inflammatory bowel diseases (IBDs) are increasingly recognized as products of the brain–gut axis associated with dysfunctions of the chronic stress response systems. The objectives of this study were to evaluate the feasibility, acceptability, and preliminary efficacy of a virtual, group-based heart rate variability (HRV) biofeedback-enhanced coping skills intervention for youth with IBD. Treatment targets included symptoms of anxiety, depression, gastrointestinal (GI) symptoms, and perceived stress.

Methods

Youth with IBD (ages 13-18) and their caregivers were randomized to either immediate treatment or waitlist control groups. The intervention consisted of 6 virtually delivered, weekly group sessions combining cognitive–behavioral therapy (CBT) with HRV biofeedback training. Outcomes included measures of anxiety, depression, GI symptoms, perceived stress, and HRV parameters. Assessments were conducted at baseline and post-intervention.

Results

Of the 53 youth randomized, 50 participated in their assigned group. The intervention demonstrated strong feasibility with 84% of participants attending at least 4 of 6 sessions. Both adolescents and parents reported strong satisfaction. Following treatment, parents reported significant decreases in adolescent depressive symptoms, anxiety symptoms, and GI symptoms compared to controls. Adolescents reported reductions in GI symptoms and perceived stress compared to controls and reductions in symptoms of anxiety within the treatment group. No changes were observed in HRV parameters.

Conclusions

This pilot study supports the feasibility and acceptability of a virtual, group-based HRV biofeedback-enhanced coping skills intervention for youth with IBD. Preliminary efficacy was demonstrated for reducing psychological and physical symptoms. Future research should evaluate efficacy in a larger, more diverse sample with elevated baseline psychological symptoms.

Inflammatory bowel diseases (IBDs), including Crohn’s disease, ulcerative colitis, and indeterminate colitis, are chronic diseases characterized by progressive and damaging inflammation of the gastrointestinal (GI) tract.¹ The course of IBD is increasingly recognized as a product of the brain–gut axis, referring to the bidirectional communications between the central nervous system, the autonomic nervous system (ANS), and the gut.²

Consistent with a brain–gut axis model, individuals with IBD, compared to healthy controls, demonstrate dysfunction of the ANS indicative of a chronic stress response which is characterized by increased sympathetic nervous system (SNS) activity and reduced parasympathetic nervous system (PNS) activity.^3,4 Though dysfunction in the stress response systems has been observed in patients with IBD, the extent to which changes in these systems affect disease and mental health symptoms is poorly understood. Dysfunction in the stress response systems has been hypothesized as contributing to GI clinical outcomes as well as elevated symptoms of anxiety, depression, and stress.⁵ It is well recognized that youth with IBD are at increased risk for developing chronic anxiety and depression.^6,7 Recent studies estimate that nearly one-quarter of adolescents with IBD experience clinically significant depressive symptoms impacting school performance, social development, and quality of life.^8–10

Heart rate variability (HRV) is a noninvasive, easy way to ascertain the measure of ANS functioning suitable for pediatrics¹¹ that has been studied in the setting of IBD.^12–14 HRV, which refers to the fluctuation in the interval between consecutive heartbeats, reflects the activating SNS and the inhibitory PNS. Low resting HRV reflects reduced parasympathetic cardiac activity and is indicative of ANS rigidity and increased emotional reactivity to stress whereas high HRV is more adaptive, reflecting flexibility within the ANS and emotional responsivity.¹⁵ Pediatric IBD studies have shown that youth with IBD have lower HRV than their healthy peers, have lower HRV when they have active disease, and that lower resting HRV predicts future disease exacerbation.^12,16 With research demonstrating lower HRV in children with IBD, and the potential negative health complications of autonomic dysfunction, clinical trials are needed to evaluate HRV-targeted interventions.

Low HRV or autonomic dysfunction can be directly targeted through biofeedback treatments.¹⁷ Biofeedback consists of real-time training in controlling one’s physiological functioning in which patients are given visual and/or auditory “feedback” on recorded physiological functioning to develop voluntary control over internal processes.¹⁸ Biofeedback has long been used to target muscle relaxation, with more recent and promising applications to HRV to treat autonomic dysfunction.^18,19 A recent meta-analysis found that HRV biofeedback is effective for decreasing self-reported ratings of stress and anxiety, including stress originating from chronic medical conditions,¹⁹ suggesting that treatments specifically targeting stress processing may be effective for reducing psychological distress as well as physical symptoms in patients with chronic GI disease.

For medically complex youth experiencing symptoms of depression and anxiety (eg, youth with cancer or chronic GI illnesses), existing evidence supports administering HRV biofeedback as an adjunctive therapy along with complementary evidence-based components from cognitive–behavioral therapy (CBT).^20–22 Two trials examining the efficacy of CBT for psychosocial concerns in youth with IBD found positive initial and follow-up outcomes related to mood, quality of life, and school attendance.^23–25 In a recent trial of CBT and mindfulness-based stress reduction for 55 adults with Crohn’s disease compared to 61 waitlist controls, treatment led to increased quality of life, decreased psychological symptoms, reduced fatigue, and increased mindfulness.²⁶ Further, those completing treatment experienced significantly reduced disease activity per patient-reported symptoms and improvements in inflammatory markers including CRP and fecal calprotectin levels. Taken together, findings demonstrate that CBT-based treatment for youth and adults with IBD may have benefits not only for psychological distress and quality of life but also for reducing clinical symptoms and improving inflammatory markers.

Promising findings from HRV biofeedback studies led us to develop a virtual, group-based HRV biofeedback-enhanced coping skills treatment protocol based on evidence-based CBT principles for treating symptoms of anxiety, depression, and stress processing in youth with IBD. The current study presents the initial outcome data from a pilot proof-of-concept trial to evaluate the feasibility, acceptability, and preliminary efficacy of the intervention. Feasibility was evaluated with regard to recruitment (goal: 40 adolescents and their parents), retention, and attendance at sessions. Acceptability was assessed via adolescent and parent-reported program satisfaction ratings. Treatment targets included symptoms of anxiety, depression, GI symptoms, and perceived stress. Regarding findings on preliminary efficacy, we expected both adolescents and parents to report reductions in symptoms of stress, depression, and anxiety. We also expected to see changes in HRV consistent with more adaptive stress processing, including increases in time-domain measures of HRV.

Methods

Participants

Participants included 51 adolescents diagnosed with IBD and their parents. Inclusion criteria were (1) diagnosis with biopsy-confirmed IBD, (2) adolescent ages 13-18 years, (3) English language proficiency, (4) home internet access and a device capable of running Zoom, and (5) enrolling with 1 parent who was willing to participate by completing questionnaires. Exclusion criteria included (1) a documented history or parent report of a developmental disorder or nonverbal presentation that would impede completion of questionnaires, and (2) a chronic illness diagnosis in addition to IBD that could reasonably contribute to greater distress or functional disability.

Procedures

All study procedures were approved by the Institutional Review Board. Participants were recruited by (1) placing study flyers in pediatric gastroenterology exam rooms at our 2 sites of recruitment in Atlanta, GA, and (2) emailing the study flyer to listservs of current IBD patients developed for research and quality improvement initiatives. Interested families were screened by research staff for inclusion and exclusion criteria and then scheduled for an informed consent discussion via Zoom. Electronic informed consent and assent were obtained for all agreeing participants via REDCap. Consenting patients were then randomized to the treatment or waitlist groups and mailed an Inner Balance sensor for study and research purposes. The Inner Balance sensor was selected for this study because it is available for retail purchase, compatible with iPhone and Android devices using a downloadable biofeedback app, portable, and has been validated in past pediatrics research.²⁷ Recruitment and randomization were rolling, with groups formed once at least 6 participants had been assigned to a treatment and waitlist group. Participants were recruited between February 25, 2022, and July 14, 2023, and 3 rounds of treatment and paired waitlist groups were held. Within 1 week of a treatment group starting, participants in that cohort completed study questionnaires via REDCap and were scheduled for a baseline HRV assessment using the Inner Balance sensor. For the 5-minute baseline assessment, participants met with a research coordinator via Zoom and were instructed to sit quietly without unnecessary movements and minimize distractions while wearing the sensor. Each participant had a 60-second habituation period prior to the 5-minute baseline recording. Participant’s data captured using the Inner Balance sensor were stored in the HeartCloud, a cloud technology available to HeartMath technology product researchers, for later download and processing.

For participants randomized to the treatment group, clinical assessments consisting of study questionnaires and the HRV assessment occurred at baseline within 1 week prior to starting treatment (Baseline, T1), at treatment end or 6 weeks after baseline (Post, T2), and at 14 weeks after baseline to capture 2-month follow-up after treatment. Participants randomized to the waitlist control group completed the same assessment protocol at the time of randomization (Baseline) and again 6 weeks later. They were then invited to begin treatment and repeated the assessments at post-test and 2-month follow-up. The current study does not include 2-month follow-up data. Participants were compensated for their time completing study assessments and attending each treatment group up to a potential maximum of $230.

Intervention development and content

The 6-week treatment protocol was based on evidence-based cognitive–behavioral therapies (CBTs) for symptoms of anxiety, depression, and stress processing. HRV biofeedback training was included as an adjunctive therapy to complement CBT coping skills. The treatment protocol was tailored to the needs of adolescents with IBD based on clinical expertise, patient feedback, and clinical evidence base such that skills were taught for general application as well as within the context of having IBD. Youth learned adaptive coping skills for managing symptoms of anxiety, depression, and symptoms of IBD including relaxation of one’s mind and body (eg, progressive muscle relaxation, guided imagery, square breathing), thought identification and modification, problem-solving, and reducing avoidance of feared situations all within a peer-supportive, group context. Each of the 6 sessions lasted 50-60 minutes. We designed the intervention to be delivered via groups to increase access to evidence-based care and so that participants could have an opportunity to give and receive peer support. Many youth with IBD have no friends or peers who are also diagnosed, and so we sought to create an environment in which learning coping skills would be enhanced through peer support.

Intervention delivery

Sessions included brief, daily homework to facilitate mastery of skills taught in the treatment program including instruction to practice HRV biofeedback for at least 5 minutes daily using the relaxation strategies taught during each session. Practice recommendations were based on past research demonstrating that a minimum of 5 minutes of HRV biofeedback training led to improved self-regulation, emotional control, and autonomic regulation.²⁸ We used multiple strategies to encourage adherence to the recommended 5 minutes of daily practice during the treatment including biweekly email reminders to participants and their parents and biweekly text message reminders occurring on alternating days. At the beginning of each group session, we problem-solved any barriers to biofeedback home practice. Participants retained their Inner Balance sensors after the 6-week treatment program to continue home practice.

Measures

Demographic and medical information

Demographic information for youth and families was collected using a standard parent-completed demographic questionnaire. Medical/disease information including diagnosis, medications prescribed, and Physician Global Assessment (PGA) of disease severity at the most recent physician visit prior to enrollment was collected via chart review. PGA is a global measure of disease severity routinely completed by the treating pediatric gastroenterologist at each medical appointment as part of the recruitment site’s participation in ImproveCareNow.²⁹ Participants are assigned a rating of quiescent, mild, moderate, or severe disease activity based on clinical symptoms, physical exam, and laboratory tests.

Treatment feasibility and acceptability

Treatment feasibility was evaluated regarding (1) meeting or surpassing recruitment goal of 40 adolescents and their parents, (2) percentage of adolescents retained throughout the course of the program, and (3) adolescent attendance rates at sessions.

Treatment acceptability was assessed via adolescent and parent-reported program satisfaction ratings using the Client Satisfaction Questionnaire (CSQ-8).³⁰ Adolescents and parents completed this 8-item survey on a 4-point scale, such that total scores ranged from 8 to 32, with higher scores indicating greater satisfaction.

Treatment outcomes

All treatment outcomes, with the exception of HRV, were assessed via both adolescent- and parent-report measures as detailed subsequently.

Depressive symptoms

Parent report of depressive symptoms was assessed using the 13-item Depression subscale of the Behavior Assessment System for Children, third edition (BASC-3).³¹ Adolescent report of depressive symptoms was assessed via the 28-item Children’s Depression Inventory, second edition (CDI-2).³² Total scores were summed and T-scores calculated using established norms for standardization. Parent and adolescent reports of depressive symptoms achieved acceptable reliability in the present sample, as assessed via Cronbach’s alpha (α range: .88-.93).

Anxiety symptoms

Parent report of anxiety symptoms was assessed using the 13-item Anxiety subscale of the BASC-3,³¹ as well as the parent report of the Screen for Child Anxiety Related Disorders measure (SCARED).³³ Adolescent report of anxiety symptoms was assessed via the 41-item SCARED.³³ Total scores were summed and T-scores calculated for parent report on BASC-3 using established norms. Parent and adolescent reports of anxiety symptoms achieved acceptable reliability in the present sample, as assessed via Cronbach’s alpha (α range: .93-.96).

Physical symptoms

Parent report of physical symptoms was assessed using the 10-item Somatization subscale of the BASC-3³¹ as well as the Children’s Somatic Symptoms Inventory (CSSI) 7-item GI Subscale.³⁴ Adolescent self-report of physical symptoms was assessed via the self-report version of the CSSI 7-item GI Subscale.³⁴ On the CSSI GI Subscale, parents and adolescents rated the extent to which the adolescent was bothered by symptoms including stomach aches, constipation, diarrhea, nausea, vomiting, feeling bloated, and food causing sickness over the past 2 weeks. Total scores were summed and T-scores calculated for parent report on BASC-3 using established norms. Parent and adolescent reports of physical symptoms achieved acceptable reliability in the present sample, as assessed via Cronbach’s alpha (α range: .89-.94).

Coping and stress responses

Stress response and coping were assessed via adolescent report on the Response to Stress Questionnaire (RSQ), IBD version.³⁵ Five factors of coping responses were assessed and proportion scores were calculated across domains: primary control engagement coping (eg, problem-solving), secondary control engagement coping (eg, cognitive restructuring), disengagement coping (eg, avoidance), involuntary engagement (eg, physiological arousal), and involuntary disengagement (eg, emotional numbing). Given scoring is based on proportions, there are no normative or standardization scores for the RSQ.

Heart rate variability

Adolescent HRV was captured via InnerBalance sensor data during pretreatment assessment (T1) and post-treatment (T2). The RR interval is the time between detected heartbeats in an interval while the NN is the normalized time between 2 detected heartbeats, factoring in potential noise or artifacts. The standard deviation (SD) of NN intervals (SDNN) and root mean square of successive RR interval differences (RMSSD) are time-domain HRV measurements calculated from these intervals. For both SDNN and RMSSD, higher values are considered more adaptive.³⁶

Data management and analytic plan

All InnerBalance HRV sensor data were accessed via HeartCloud and stored on a local computer using the emWave Pro software. Raw assessment data were processed using the Kubios HRV software, a full-featured HRV analysis software for scientific research compatible with InnerBalance devices and emWave Pro software. Kubios software processes raw HRV data files to provide all relevant HRV parameters including time and frequency-domain measures, respiration rate, and heart rate.

Continuous variables are shown as means and SDs while categorical variables are shown as counts and proportions. We evaluated the longitudinal difference between treatment and control groups through mixed effect models where subjects acted as random effects and baseline value of the outcome, treatment group, time, and interaction between treatment group and time acted as fixed effects. A compound symmetry structure was used for analysis. The difference between baseline (T1) and post (T2) timepoints for treatment and control groups was evaluated within groups, and the difference between treatment and control groups at post T2 was also evaluated through least square mean differences, 95% confidence intervals, and P-values. Effect sizes were calculated as the difference in means divided by the pooled SD of the outcome at baseline to coincide with Cohen’s d where an effect size of 0.2 is considered small, 0.5 moderate, and 0.8 as large. All analyses were conducted in SAS 9.4. A P-value below .05 was considered significant and all tests were 2-sided.

Results

Participant Demographics

See Table 1 for full demographic details. Adolescent participants were on average 15 years old (SD = 1.46) and the majority were female (n = 31; 61%). Most caregivers were biological mothers (n = 46; 94%), with an estimated family income above $150 000 (n = 21; 43%). Crohn’s disease was the most prevalent IBD diagnosis (n = 36; 71%), with an average time since diagnosis of 3.22 years (SD = 2.69).

Feasibility

Recruitment

Given the virtual delivery of the intervention, youths were recruited from across the entire geographical catchment area served by the sites of recruitment, with 1 participant living over 300 miles from the medical center. See Figure 1 for a consort diagram of progress through the phases of this randomized, waitlist control trial. Seventy-three youths were contacted for interest after being referred by their medical team or responding to advertisements. Of these, 14 declined further interest once contacted, and 59 were screened for eligibility. Following screening, 7 were excluded for not meeting inclusion criteria. Fifty-three youths consented and were randomized, with 2 youths deciding to discontinue participation prior to completing baseline assessments, leaving 51 youths who completed the baseline assessments. Of those, 50 participated in their assigned treatment groups (n = 26 in treatment group and n = 27 in waitlist group); 3 did not receive the allocated intervention for various reasons as shown in Figure 1. All randomized participants were included in the analysis, including those who did not complete treatment. No adverse events were reported. Study enrollment ended after recruitment goals were met.

Retention

Of the 50 participants who began their assigned intervention groups, 84% attended at least 4 of the 6 training sessions. Throughout the course of the intervention groups, 2 participants discontinued attending and were lost to follow-up despite multiple attempts to reengage the youth and family in treatment.

Intervention fidelity

Strategies to maximize intervention treatment fidelity were implemented across all stages of trial design and implementation. Each session of the intervention was manualized to include the aims of each session and detailed, scripted language for introducing each of the skills learned. Each session’s scripted language had an accompanying slide presentation that a group leader used to present skills and encourage participant engagement. Each group was led by a licensed psychologist paired with a doctoral-level psychology trainee who met with the same cohort for each of the 6 sessions. All group leaders, regardless of training level, met with the intervention creator (final author) to receive training in each of the 6 sessions. Each week of the 6-session intervention, the leader dyads met to go over that week’s session plan and review skills to be taught in session. At the beginning of each session after the first, leaders asked AYA participants to verbally review the skills learned in the previous session and to ask questions. If the absence of a group leader was required, a group leader who had received training in leading the sessions substituted.

Acceptability

Adolescents and parents individually reported their satisfaction with the intervention using the CSQ-8, and they noted similar mean scores (Table 2). On item 7, adolescents (M = 3.53, SD = 0.67) and parents (M = 3.63, SD = 0.49) reported their overall satisfaction with scores averaging close to the highest score, 4. When looking at total scores, for adolescents, their scores ranged from 18 to 32 (M = 28.02, SD = 2.90), and for parents, their scores ranged from 20 to 32 (M = 28.73, SD = 3.18). For both reports, 32 is the highest possible score, indicating the highest level of satisfaction.

Treatment Outcomes

Depressive symptoms

See Table 3 for full details of treatment outcomes and Table S1 for means and SDs. At baseline assessment, 29% of participants and 31% of parents endorsed clinically elevated levels of depressive symptoms. Parent report of adolescent depressive symptoms decreased over time (T1 to T2) within the treatment group (Mean difference: −3.64, 95% CI −7.21, −0.07, P < .05) and was significantly lower for the treatment group compared to the control group at post-T2 (Mean difference: −3.45, 95% CI −6.77, −0.12, P < .05), suggesting improvements in parent report of adolescent depressive symptoms over the course of participation in intervention. Conversely, adolescent self-report of depressive symptoms did not differ over time for the treatment group (Mean difference: −1.99, 95% CI −4.44, 0.47) and there were no group differences between treatment and control in self-reported depressive symptoms at post-T2 (−1.99, 95% CI −4.38, 0.41).

Anxiety symptoms

At baseline assessment, 61% of youth and 47% of parents endorsed clinically elevated levels of anxiety symptoms. Parent report of adolescent anxiety symptoms decreased over time (T1 to T2) within the treatment group (Mean difference: −3.21, 95% CI −5.64, −0.78, P < .05) and was significantly lower for the treatment group compared to the control group at post-T2 (Mean difference: −3.50, 95% CI −5.94, −1.07 P < .05), indicating improvements in parent report of adolescent anxiety symptoms over the course of participation in intervention. Adolescent self-report of anxiety symptoms decreased over time following participation in the intervention (T1 to T2) within the treatment group (Mean difference: −5.05, 95% CI –9.69, −0.4, P < .05). Treatment group self-reported anxiety symptoms were not statistically significantly lower than the control group at post-T2 (Mean difference: −4.29, 95% CI –8.7, 0.12, P = .06); however, this result did indicate a small effect size (d = 0.27), suggesting possible clinical significance in difference across groups after treatment group participation in intervention.

Physical symptoms

Both parent and adolescent reports of physical symptoms were significantly lower in the treatment group when compared to the control group at post T2 (Parent CSSI GI Subscale mean difference: −2.58, 95% CI −4.28, −0.88, P < .05; Adolescent CSSI GI Subscale mean difference: −1.82, 95% CI −3.39, −0.25, P < .05). Further, parent report of somatization symptoms decreased significantly over time (T1 to T2) within the treatment group (Mean difference: −3.17, 95% CI –6.22, −0.12, P < .05).

Coping and stress response

Adolescent-reported perceived stress decreased over time within the treatment group with a moderate effect (Mean difference: −0.45, 95% CI –0.67, −0.23, P < .001; d = 0.63) and was significantly lower for the treatment group compared to the control group at post-T2 with a moderate effect (Mean difference: −0.45, 95% CI –0.65, −0.24, P < .001; d = 0.63). There were no statistically significant differences over time among treatment groups nor differences in treatment and control group reported proportions of coping strategies in response to stress. However, there were small effects in an increased proportion of use of primary control engagement coping (d = 0.33) and involuntary disengagement coping (d = 0.30) for the treatment group at post-T2 compared to control group.

Heart rate variability

There were no statistically significant differences in SDNN over time for the treatment group (Mean difference: 15.6, 95% CI −2.12, 33.32); however, there was a small effect size such that the level of HRV as assessed via SDNN increased for the treatment group from T1 to T2 at a clinically significant level (d = 0.43). However, the control group also had an increase in SDNN (Mean difference: 16.74, 95% CI 0.99, 32.49) over time. There was no difference between the treatment and control groups at post-T2 (Mean difference: 4.9, 95% CI −13.12, 22.92). RMSSD did not change over time for the treatment (Mean difference: −4.09, 95% CI −27.64, 19.47) or control group (Mean difference: 16.02, 95% CI −4.86, 36.91) and there was no difference between the treatment and control groups at post-T2 (Mean difference: −14.75, 95% CI −38.98, 9.48).

Discussion

This study evaluated pilot data from a proof-of-concept trial for a virtual, group-based HRV biofeedback-enhanced coping skills intervention for youth with IBD. The goal was to evaluate the feasibility, acceptability, and preliminary efficacy of the trial. Analyses demonstrated the trial was feasible, with high rates of participant retention, and was executed with fidelity. Additionally, both adolescent participants and their parents reported they were highly satisfied with the intervention. Regarding intervention efficacy, psychological symptoms, physical symptoms, coping and response to stress, and HRV were examined with mixed findings.

For adolescents who completed the intervention, parents reported their adolescents had fewer depressive symptoms, anxiety symptoms, and GI-specific physical symptoms after they received the intervention. From the adolescents’ report, they had fewer anxiety symptoms, physical symptoms, and less perceived stress after receiving the intervention. The decrease in parent and patient-reported GI-specific physical symptoms is especially promising with regards to clinical utility and compliments previous research in adults who demonstrated improvements in disease symptoms following CBT intervention.²⁶ No change was demonstrated in adolescent-reported depressive symptoms. Additionally, although adolescents reported fewer anxiety symptoms after completing the intervention, this was not significantly different from the control group’s anxiety scores at this time point. However, there was a small effect size, which may indicate a lack of power to accurately examine this difference. Alternatively, the lack of significant treatment effects may be due to a restricted range of possible improvement since relatively low levels of symptoms were reported. Discrepant parent and youth reports of mental health symptoms are not uncommon,³⁷ with each piece of information providing valuable context. The discrepancies may also be partially accounted for by using different measures for youth and parent reports. In addition to internalizing symptoms, it was important to examine whether the skills taught during the intervention translated to changes in adolescents’ reports of coping strategies.

There were no statistically significant differences in reported proportions of coping strategies in response to stress. However, there were small effect sizes observed when comparing the treatment group to the control group at post-T2 suggesting an increase in the use of adaptive coping strategies (primary control engagement coping) and a decrease in the use of maladaptive, avoidant coping strategies (involuntary disengagement coping). Given this was a pilot study, it will be important to examine the impact of the intervention on coping strategies for a larger sample to determine if effect sizes are reproducible and whether a small sample size limited the ability to detect change.

Regarding HRV outcomes, there were no differences in SDNN and RMSSD for those who participated in the intervention and those who were in the control group at post-T2. There was a small effect size, demonstrating an increase in SDNN after intervention completion, but the control group also had an increase in SDNN over time. Adherence data on whether participants practiced their biofeedback was not collected and would be important to better understand whether these findings are at least partially attributable to lack of biofeedback engagement. Evidence has shown that several classes of medications can affect HRV including antidepressants, antiarrhythmics, beta-blockers, calcium-channel blockers, and sedatives/anesthetics. In the current literature, it remains unclear whether drugs used by pediatric patients with IBD may have an impact on HRV. The effect of anti-TNF treatment on the sympathetic and PNS, and hence on HRV, remains unclear.³⁸ In future, larger trials, it will be important to characterize all drugs taken by patients and evaluate with regards to HRV response and outcomes.

Compared to previous psychological interventions designed for youth with IBD, the current intervention was unique in its use of HRV biofeedback as an adjunct skill to CBT. Some of the first studies testing CBT among youth with IBD focused on symptoms of depression and therefore included depressive symptoms as an inclusion criterion.²³ As would be anticipated from nonchronic illness samples, improvements in both child- and parent-reported depressive symptoms were observed³⁹ and maintained at 1 year.²⁴ In a previous trial of 185 youths with IBD, those randomized to 3 individual and parent sessions of CBT reported improvements in child-reported quality of life and parent-reported coping strategies.²⁵ No differences were observed in symptoms of anxiety or depression between those receiving CBT compared to the control condition, though the sample reported low levels of symptoms on average. Compared to this trial, our intervention included 6 sessions, was group-based, and focused more heavily on individual skills including HRV biofeedback for managing stress-related symptoms. Future research will be needed to determine which components of CBT-based interventions are responsible for a change in specific outcomes (eg, anxiety and depression compared to coping skills).

This CBT-based pilot intervention taught the adolescents new skills each week, including multiple relaxation techniques, thought identification and restructuring, HRV biofeedback, and pleasant activity scheduling. Additionally, the interventionists noticed that the context in which this was delivered, a supportive peer environment, appeared to provide a valuable space for validation and support of common medical experiences. Further research is needed to examine specific mechanisms of change for the observed findings, but some hypotheses are described. The relaxation techniques and cognitive restructuring could have provided the adolescents with strategies for coping with challenging emotions or situations contributing to the changes and effect sizes in perceived stress and primary control engagement coping. Pleasant activity scheduling distraction techniques learned may account for the small effect noticed in adolescents using more involuntary disengagement coping. It will be important for future studies to examine whether there is a positive impact of a group-delivered intervention on variables such as isolation and social support.

This study is not without limitations, which highlights future research directions. As this was a pilot trial, the current sample was small and recruited from 1 geographical region in the Southeastern United States. Further, the current sample was predominantly White and high income with low baseline levels of psychological distress, on average. In future trials, we aim to recruit a more sociodemographically diverse sample of youth with IBD and to include a positive screen for symptoms of anxiety and depression as an inclusion criterion. Future research should also track engagement with and adherence to the biofeedback training outside of the session to determine the extent to which any observed change is associated with the dosage of practice. Additionally, the current study design is unable to compare the biofeedback-enhanced treatment to the coping skills group treatment alone or delivered individually. Regarding effectiveness, biweekly email and text reminders to engage in skills practice may not be generalized outside of a clinical trial.

In conclusion, the current study supports the feasibility and acceptability of a virtual, group-based HRV biofeedback-enhanced coping skills intervention for youth with IBD. The use of a virtual format allowed youth from across our geographically large clinical catchment area to access weekly evidence-based therapy in addition to peer support. Adjunctive HRV biofeedback was acceptable to families and delivered using mobile hardware with cloud-based software for data acquisition. Preliminary efficacy was demonstrated with regard to adolescent-reported symptoms of anxiety, physical GI symptoms, and stress. Parents reported improvements in adolescents’ depressive and anxiety symptoms as well as physical GI symptoms. Findings support a larger clinical trial to evaluate efficacy in a fully powered sample reporting elevated symptoms of anxiety and depression.

Funding

This research was supported by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the National Institutes of Health under Award Number K23DK122115.

Conflicts of Interest

None declared.

References