Study of Affect Induction for Lab Induced Pain in Healthy Undergraduates

Feasibility and Efficacy of a Mindfulness-enhanced Positive Affect Induction for Experimentally Induced Pain

The goal of this clinical trial is to test if a mindfulness-enhanced positive affect induction (MPAI) works well to reduce pain intensity and pain unpleasantness from a cold water pain test in undergraduate college students who do not endorse ongoing medical or mental health diagnoses. The main questions it aims to answer are:

• Is the MPAI a feasible and acceptable psychological technique for managing brief pain?
• Does the MPAI work well to reduce pain intensity and unpleasantness from experimentally induced brief pain, compared to those using a breathing meditation or those instructed to respond naturally.
• Does using the MPAI work well to improve confidence in self-managing brief pain?

Participants will be asked to complete questionnaires about their sleep, pain beliefs, and emotions after consenting to participate and at the end of the study session. They will then be randomized to either:

• Use the MPAI for managing pain induced by a cold water test (placing their hand in a container of cold water kept at approximately 5 degrees Celsius).
• Use a breathing meditation for managing pain induced by a cold water test (placing their hand in a container of cold water kept at approximately 5 degrees Celsius).
• Respond naturally to pain induced by a cold water test (placing their hand in a container of cold water kept at approximately 5 degrees Celsius).

Researchers will compare the MPAI group to the breathing meditation and natural response groups to see if the MPAI group reports less pain from the cold water test and

The purpose of the study is to assess the following aims:

Aim 1: Examine the feasibility and acceptability of a mindfulness-enhanced positive affect induction (MPAI) for improving the experience of experimentally-induced pain.

Aim 2: Examine the efficacy of the MPAI in reducing pain intensity and increasing pain tolerance.

Aim 3: Examine change in self-efficacy in pain management from before and after using the MPAI.

Recruitment:

Participants will be recruited via the University of Colorado (CU) Denver Psychology Participant Pool website (Sona system), a resource for undergraduate Psychology students to participate in research projects. Interested participants will be provided inclusion/exclusion criteria and instructed to register for a study session only if they meet those criteria. Inclusion/exclusion criteria will be confirmed by study research assistants (RAs) during the informed consent process. Participants will receive course credit for participation in the study. If students do not wish to participate in the study, an alternative assignment will be available for equal credit.

The target population will consist of a convenience sample of healthy undergraduate students at CU Denver. While this population does not generalize to populations with chronic pain, as this is the first study of this particular affect induction for pain, the primary goal is to assess general feasibility and efficacy, which may influence future research specific to chronic pain populations. The population will be randomized into three experimental groups: MPAI, breathing meditation (BM), and natural response (NR). The BM and NR groups will serve active comparison and control groups respectively. Each group will consist of 46 participants (N=138) based on power analyses accounting for medium effects found in similar studies. Final power analyses were conducted for planned ANCOVAs with f = 0.27, alpha = 0.05, and power = 0.80.

Phone screening will occur in instances in which participants contact study personnel via methods other than CU Denver's Sona system (e.g., via phone or email). Screening questions will not go beyond inclusion criteria listed on an approved study advertisement. No information will be recorded on specific inclusion/exclusion criteria met. Additionally, participants do not provide specific medical details during the consent process. Participants only indicate if they do or do not meet all inclusion/exclusion criteria.

Study Procedures:

Participants will come into the laboratory, provide informed consent, be randomized to one of three groups (natural response, breathing meditation, or positive affect induction) and will complete forms and questionnaires on demographics, sleep quality, positive and negative affect, present-moment affect, pain catastrophizing, mood states (e.g., anger and fatigue), present-moment anxiety, and self-efficacy of pain management. Participants will then receive instructions and practice for their randomized group assignment (e.g., on how to use the positive affect induction). Participants will then complete a cold pressor task (CPT) while using the strategy they were instructed to use (i.e., naturally responding, using breathing meditation, or using the positive affect induction). Importantly, participants will be instructed to begin with their strategy 5 minutes prior to beginning the CPT, to ensure the strategy may have an effect during the CPT, which has a maximum duration of 5 minutes. Participants will then complete a final brief questionnaire rating their pain intensity, pain unpleasantness, present moment affect, self-efficacy of pain management, and feasibility and acceptability of the strategy used.

The CPT is an acute pain task wherein participants put their hand in a cold-water bath. Ice packs will be used within the water bucket to maintain a temperature no greater than 41.0 degrees Fahrenheit (5 degrees Celsius), and participants will have their hand in the water for no greater than five minutes (a maximum time limit of five minutes will be set to prevent any adverse, hypothermic effects from the cold water). The participant will provide both subjective (self-report pain intensity and unpleasantness) and objective (observation of/timed contact with water) measures from the acute pain task. Self-report measures will be taken directly following the CPT. Pain tolerance will be measured via timing when participants remove their hand from the water. The participants will be timed for how long they keep their hand in the water (observation of contact).

Data Collection & Management:

Electronic case report forms and study data management will be performed using the REDCap Study Data Management System through the Colorado Clinical and Translational Sciences Institute (CCTSI) Informatics Core. REDCap is a HIPAA-compliant research data management system developed at Vanderbilt University and deployed at over 1500 institutions. At CU Denver-Anschutz, REDCap is supported by the Office of Information Technology's Development and Informatics Service Center (DISC) and the CCTSI Informatics Core. The CU Denver REDCap installation has passed a rigorous 6-week security threat analysis performed by the CU Denver-Anschutz HIPAA Security Officer. All study data are stored on a secure database server which is separate from the web-facing server -- a best-practices for internet-based security. All user access requires unique user accounts and passwords. All user actions are recorded in a secure audit log. The database server is routinely backed-up. All security patches and application updates are applied immediately upon release by DISC.

Unanticipated Problems/Adverse Events Reporting:

Unanticipated problems and adverse events will be reported to the Colorado Multiple Institutional Review Board within 5 days of an event.

Statistical Analysis Plan:

Data quality checks will be performed to ensure data included in analyses are interpretable, consistent, and within range.

Manipulation Checks:

To assess whether the affect induction and breathing meditation increase positive affect, paired t-tests will be conducted on present-moment affect measures from baseline and post-CPT questionnaires.

Aim 1 To assess feasibility, a one-way ANOVA will be run between groups as a manipulation check for MPAI efficacy. Means, standard deviations, and percentages will additionally be calculated for feasibility and acceptability items. Good feasibility and acceptability will be considered by an a priori threshold of high participant mean ratings (≥80%) for each item.

Aim 2 To assess efficacy of the MPAI on pain from the CPT, one-way ANCOVAs will be calculated to analyze omnibus between-group effects for each pain measure (i.e., for CPT pain tolerance, intensity, and unpleasantness). Post-hoc comparisons will then be calculated to determine specific group differences (e.g., PA vs BM, PA vs NR, and BM vs NR). Correlation analyses will be run on all covariates, to assess for multicollinearity prior to inclusion in ANCOVA analyses. Covariates to be analyzed include: Patient Reported Outcomes Measurement Information System (PROMIS) sleep disturbance (past seven days), PANAS (positive and negative affect past seven days), baseline present-moment affect, pain catastrophizing, present-moment anxiety, baseline PBQ (self-efficacy of pain management), gender, and meditation experience.

Aim 3 To assess for change in self-efficacy in pain management, a paired t-test will be calculated between baseline and post-CPT PBQ scores. A linear mixed model will additionally be calculated to assess change differences between groups; however, as the primary goal of Aim 3 is not to assess between group changes in pain management self-efficacy, this will be an exploratory analysis.

Study Hypotheses:

Aim1. Hypothesis 1. It is hypothesized that the mindfulness-enhanced positive affect induction will have good feasibility and acceptability for improving the experience of experimentally induced pain, based on an a priori threshold of ≥80% mean ratings on related measures.

Aim 2. Hypothesis 1. Compared to the BM and NR groups, the MPAI will result in significantly greater pain tolerance, less pain intensity, and less pain unpleasantness in relation to the experimentally induced pain.

Aim 3. Hypothesis 1. Self-efficacy in pain management will significantly increase from baseline to post-CPT, for the MPAI and BM groups.

Hypothesis 2. A repeated measures ANOVA will show increased PBQ scores for the MPAI and BM groups; however, no changes in PBQ

Inclusion Criteria:

• University of Colorado Students
• Age 18-65
• Fluent in written and spoken English

Exclusion Criteria:

• Presence of an untreated mood or psychiatric disorder
• Presence of a current chronic pain condition
• Presence or history of Reynaud's syndrome, peripheral neuropathy, or unstable heart condition (including myocardial infarction, abnormal heart rhythms, or hypertension)
• Current use of prescription pain medication, high-dose anti-psychotics, selective serotonin re-uptake inhibitors (SSRIs), benzodiazepines, or gabapentin
• Day-of over the counter pain medication use
• Marijuana, Cannabidiol (CBD), or psilocybin use within three days of study participation (recency of use assessed via self-report)
• Food, caffeine, and nicotine are not to be had within 30 minutes of cold pressor test (nicotine patch not exclusionary due to stable/consistent state).