Evaluating the Feasibility, Acceptability, and Preliminary Outcomes of Heart Rate Variability Biofeedback for Individuals With Opioid Use Disorder.

The goal of this clinical trial is to evaluate the feasibility, acceptability, and preliminary outcomes of a heart rate variability biofeedback (HRVB) intervention among adults with opioid use disorder (OUD) receiving residential treatment. The study aims to learn whether HRVB can be implemented successfully in this setting and whether it may help participants manage stress, emotional regulation, and cravings.

The main questions this study aims to answer are:

Is HRVB feasible and acceptable for adults with OUD in a residential treatment program, as indicated by recruitment, retention, adherence, and participant satisfaction?

Do participants show preliminary improvements in stress, affect, emotional regulation, self-efficacy, and cravings following participation in the HRVB intervention?

Participants will be adults with OUD enrolled in a residential treatment program.

Participants will:

1. Complete baseline and post-intervention questionnaires assessing stress, affect, emotional regulation, social support, self-efficacy, and cravings
2. Participate in daily HRVB practice using a portable biofeedback device for approximately 3 weeks
3. Complete brief daily diary assessments related to mood, stress, and cravings

This is a single-arm pilot study designed to inform the feasibility and future refinement of HRVB as an adjunct intervention for individuals with OUD in residential treatment settings.

Study Overview

• Status: Completed
• Conditions: Stress; Recovery; Opioid Use Disorder; Emotional Regulation; Autonomic Nervous System Imbalance; Opioid Craving; Biofeedback; Positive and Negative Affect; Breathing Techniques; Heart Rate Variability (HRV)
• Intervention / Treatment: Behavioral: Heart rate variability biofeedback

• Study Type: Interventional
• Enrollment (Actual): 32
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Phoenix, Arizona, United States, 85004
      • Arizona State University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Eligible participants are

  1. adults aged 18 to 65,
  2. currently admitted to a transitional living program for opioid use and within the first 30 days of admission
  3. voluntarily agree to participate and demonstrate adequate decision-making capacity as determined by the study team during informed consent
  4. able to read and speak English,
  5. have a clinical diagnosis of OUD at any severity level, whether mild, moderate, or severe,
  6. identify opioids as their primary drug of choice
  7. should have access to smartphones for daily individual practice of the intervention.
  8. must reside at the treatment program for the duration of the study

Exclusion Criteria:

1. inability to provide informed consent,
2. inability to demonstrate adequate decision-making capacity
3. currently having suicidal thoughts or psychotic symptoms
4. history of receiving previous HRVB training,
5. have a serious cardiac condition such as having pacemaker, heart failure or cardiac arrhythmia),
6. a known self-reported diagnosis of dementia, a severe brain injury, or a serious neurological condition(e.g., Parkinson's disease)
7. currently enrolled in any other biofeedback program simultaneously
8. currently taking medications such as MAOIs and alpha/beta blockers or benzodiazepines.

Participant recruitment will be conducted at the recruitment site. Individuals younger than 18 or older than 65 years are excluded from participation primarily due to age-related differences in autonomic function and heart rate variability (HRV) regulation. Restricting the sample to adults aged 18-65 allows for more accurate measurement and interpretation of HRV data, thereby reducing potential confounding effects related to age-related physiological differences.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: HRVB Intervention group

Behavioral: Heart rate variability biofeedback; Participants non-randomized to the single intervention arm will receive a standardized HRV sensor and accompanying smartphone application, along with a 30-45-minute HRVB training session focused on using biofeedback signals to generate a resonant frequency pattern of HRV (coherence) following baseline data collection. Participants will be asked to practice their HRVB skills at home for 10 minutes per day over a 3-week period.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Recruitment Rate (Feasibility)	Recruitment feasibility will be assessed as the proportion of eligible individuals who enroll in the HRVB intervention during the recruitment period in the transitional residential treatment setting. Metric: Number of participants enrolled ÷ number of eligible individuals Unit of Measure: Percentage (%) of eligible individuals enrolled Benchmark: ≥ 60% enrollment of eligible individuals	From study launch through completion of recruitment
Retention Rate (Feasibility)	Description: Retention feasibility will be assessed as the proportion of enrolled participants who complete post-intervention (T2) assessments at the end of the 3-week HRVB intervention. Metric: Number of participants completing T2 ÷ number of participants enrolled Unit of Measure: Percentage (%) of enrolled participants completing T2 Benchmark: ≥ 80% completion of post-intervention assessments	Time Frame: From enrollment through completion of the 3-week intervention
HRVB Practice Adherence (Feasibility)	Description: Adherence feasibility will be assessed as the proportion of participants who engage in consistent daily HRVB practice across the intervention period. Self-reported adherence will be corroborated using HeartCloud device data. Metric: Number of participants practicing on ≥70% of intervention days ÷ total number of participants Unit of Measure: Percentage (%) of participants meeting adherence threshold Benchmark: ≥ 70% of participants practice on ≥70% of intervention days	From enrollment through completion of the 3-week intervention
Daily Diary Compliance (Feasibility)	Description: Daily diary compliance will be assessed as the proportion of expected ecological momentary assessment (EMA) diary entries completed during the intervention period. Metric: Number of completed diary entries ÷ number of expected diary entries Unit of Measure: Percentage (%) of expected diary entries completed Benchmark: ≥ 80% of daily diary entries completed	From enrollment through completion of the 3-week intervention
Intervention Acceptability Rating (Acceptability)	Acceptability will be assessed at post-intervention (T2) using a structured 7-item survey evaluating perceived relevance, helpfulness, usability, satisfaction, and likelihood of recommending the intervention. Items are rated on a 5-point Likert scale (1 = strongly disagree/not helpful to 5 = strongly agree/very helpful). Metric: Number of participants rating items as 4 or 5 ÷ total number of respondents Unit of Measure: Percentage (%) of participants endorsing the acceptability threshold Benchmark: ≥ 80% of participants rate the intervention as helpful or very helpful (scores 4-5).	At the post-intervention assessment (T2), immediately following completion of the intervention
Qualitative Acceptability Feedback (Acceptability)	Qualitative acceptability will be assessed using open-ended questions examining perceived benefits, challenges, and recommendations for improvement of the HRVB intervention. Metric: Thematic saturation and frequency of key themes Unit of Measure: Narrative themes categorized as benefits, barriers, and recommendations Benchmark: Identification of actionable themes supporting feasibility and refinement of implementation.	At the post-intervention assessment (T2), immediately following completion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Perceived Sress	Perceived stress will be measured using the 10-item Perceived Stress Scale (PSS-10), a validated self-report questionnaire that assesses the degree to which individuals perceive their lives as unpredictable, uncontrollable, and overwhelming during the past month. Higher scores indicate greater perceived stress.	Baseline (T1) and 3 weeks after baseline (T2)
Perceived Affect	Affect will be measured using the Positive and Negative Affect Schedule (PANAS-SF, 20 items), a validated self-report measure that assesses the extent of positive affect (e.g., enthusiasm, alertness) and negative affect (e.g., distress, irritability) experienced over a specified time period. Higher scores indicate greater levels of the respective affective state. In addition, affect will be assessed through a brief daily diary using 12 PANAS-derived items to capture day-to-day fluctuations in positive and negative affect, providing a more nuanced understanding of affect over the 3-week study period.	Baseline (T1) and 3 weeks after baseline (T2)
Perceived difficulties in emotional regulation	Perceived difficulties in emotional regulation will be measured using the Difficulties in Emotion Regulation Scale-Short Form (DERS-16), which is a validated self-report instrument that assesses global impairments in emotion regulation across multiple domains. It evaluates the frequency with which individuals experience problems such as heightened emotional reactivity, nonacceptance of emotional responses, difficulties maintaining goal-directed behavior when distressed, challenges controlling impulses during negative affect, and limited perceived access to effective emotion regulation strategies. Higher total scores reflect greater overall difficulty in regulating emotions.	Baseline (T1) and 3 weeks after baseline (T2)
Craving for illicit opioids	Cravings for illicit opioids will be measured using the Obsessive Compulsive Drug Use Scale (OCDUS). This tool will be used to assess craving severity, capturing obsessive thoughts about substance use, compulsive urges, and perceived control over craving-related cognitions and behaviors. Higher scores indicate greater craving intensity and preoccupation with drug use. In addition, craving will be monitored through a brief daily diary item assessing subjective craving severity, allowing examination of day-to-day fluctuations and temporal patterns in craving experiences across the study period.	Baseline (T1) and 3 weeks after baseline (T2)
Perceived social support	Perceived social support will be measured using The Multidimensional Scale of Perceived Social Support (MSPSS), which is a validated self-report instrument that assesses perceived adequacy of social support from three primary sources: family, friends, and significant others. It evaluates individuals' subjective sense of being valued, understood, and supported emotionally and practically by their social networks. Higher scores indicate greater perceived availability and quality of social support across these domains.	Baseline (T1) and 3 weeks after baseline (T2)
Self-efficacy to resist substance use	The Drug-Taking Confidence Questionnaire-8 (DTCQ-8) is a brief, validated self-report measure of self-efficacy to resist substance use across high-risk situations. It assesses an individual's perceived confidence in their ability to refrain from using drugs when experiencing common triggers such as negative emotions, social pressure, craving, or interpersonal conflict. Higher scores indicate greater confidence in resisting drug use and a lower likelihood of relapse in these situations.	Baseline (T1) and 3 weeks after baseline (T2)
Autonomic regulation	Heart rate variability (HRV) metrics, including SDNN, RMSSD, mean heart rate, mean interbeat interval (IBI), total power, LF, HF, and LF/HF ratio, will be used as objective indicators of autonomic nervous system functioning, reflecting overall variability, parasympathetic activity, and sympathetic-parasympathetic balance. In addition, normalized coherence scores from daily HeartMath Inner Balance practice will assess the degree of physiological synchronization and autonomic efficiency. Together, these measures provide complementary indices of autonomic regulation, stress resilience, and emotional regulation capacity, with higher variability and coherence generally indicating healthier autonomic functioning.	Baseline (T1) and 3 weeks after baseline (T2)

Collaborators and Investigators

• Sponsor: Arizona State University

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2025
• Primary Completion (Actual): February 1, 2026
• Study Completion (Actual): February 1, 2026

Study Registration Dates

• First Submitted: December 20, 2025
• First Submitted That Met QC Criteria: January 15, 2026
• First Posted (Actual): January 23, 2026

Study Record Updates

• Last Update Posted (Actual): May 15, 2026
• Last Update Submitted That Met QC Criteria: May 13, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: opioid use disorder; heart rate variability biofeedback; daily diary; adjunct intervention; app based intervention; opioid cravings
• Additional Relevant MeSH Terms: Narcotic-Related Disorders; Mental Disorders; Substance-Related Disorders; Chemically-Induced Disorders; Behavior; Social Behavior; Self-Control; Opioid-Related Disorders; Emotional Regulation
• Other Study ID Numbers: STUDY00022883

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No