Perceived Social Support, Heart Rate Variability, and Hopelessness in Patients With Ischemic Heart Disease
Condition: Ischemic Heart Disease
MeSH terms: Heart Diseases; Myocardial Ischemia; Coronary Artery Disease; Ischemia
Study type: Observational

Summary: 
      Cardiovascular disease is the leading cause of death worldwide, with ischemic heart disease
      (IHD) the leading cause of cardiovascular mortality. Persons with IHD suffering from
      psychological distress, including hopelessness, are more likely to die from IHD. Following a
      stressful event, the vagus nerve enables activation of either a sympathetic (fight/flight) or
      parasympathetic (rest/digest) response. Heart rate variability (HRV), the beat-to-beat
      variability between normal successive heart beats, is a biomarker of both adaptive and
      maladaptive reactions to stress. Decreased HRV predicts greater risk for morbidity and
      mortality and is associated with poor mental health outcomes in persons with IHD. As stated
      by polyvagal theory, HRV may be influenced by social support. Decreased perceived social
      support (PSS), a social determinant of cardiovascular risk, is predictive of increased
      morbidity and mortality in persons with IHD. Decreased PSS has been associated with
      hopelessness in patients with cancer, but this relationship has not been studied in IHD
      beyond the applicant's small pilot study of patients with hopelessness. Hopelessness, a
      negative outlook and sense of helplessness about the future, is present in 27-52% of patients
      with IHD. This is of grave concern, because hopelessness is associated with a 3.4 times
      increased risk of mortality and nonfatal myocardial infarction in patients with IHD,
      independent of depression. This research focuses on understanding the biological (HRV) and
      social (PSS) aspects of hopelessness, with the long-term goal of developing and testing novel
      interventions to reduce the adverse effects of hopelessness and improve health outcomes in
      patients with IHD. Participants for this cross-sectional study will be recruited while
      hospitalized for an IHD event. Participants will include patients who report moderate to
      severe hopelessness from the sponsor's NIH-funded study (n = 225); additional patients with
      minimal to no hopelessness will be recruited and enrolled by the applicant (n = 45). Data
      collection will take place remotely two weeks after hospital discharge. Specific aims
      include: Aim 1) Evaluate the relationship between HRV and hopelessness in patients with IHD;
      Aim 2) Determine the relationship between PSS and hopelessness in patients with IHD; and Aim
      3) Explore the possible mediating effect of HRV on the relationship between PSS and
      hopelessness in patients with IHD.
    

Detailed description: 
      Design, Sample, and Setting. A cross-sectional design will be used to address study aims.
      Data will be collected 2 weeks after hospital discharge for an IHD event. Patients who
      provide written-informed consent and enroll will be sent a package with study materials to
      their home and complete a phone visit 2 weeks after hospital discharge. Comorbidities and
      clinical characteristics will be abstracted from the medical record. Recruitment and
      enrollment of all patients will take place during patients' hospitalization for an IHD event
      at a large teaching hospital in the Midwestern United States. The applicant will analyze data
      from Dr. Dunn's NIH-funded study (R01NR017649) of 225 patients with IHD who report moderate
      to severe hopelessness and will additionally recruit 45 sex and age matched patients with IHD
      who report minimal to no hopelessness.

      Recruitment, Screening and Consent. Study enrollers, employed by the recruiting hospital,
      will determine eligibility for hopelessness screening by reviewing the patient's medical
      record. Eligible hospitalized IHD patients will be called by enrollers and invited to screen
      for hopelessness over the phone. Enrollers will use a script to introduce the screening
      portion of the study, explaining that eligibility for Dr. Dunn's study (enrolling those who
      report moderate to severe hopelessness) and the applicant's study (enrolling those with
      minimal or no hopelessness) will depend on screening results. Interested patients will
      provide consent for the hopelessness screening, including a HIPAA waiver. Patients who
      provide consent will be screened for hopelessness using the 10-item state subscale of the
      23-item State-Trait Hopelessness Scale (STHS). Based on published cut-point criteria, a
      criterion of ≥ 1.8 will be used for classification of moderate to severe hopelessness levels.
      Patients who score ≥ 1.8 during screening will be asked to participate in Dr. Dunn's study,
      and the applicant will have access to this data. Patients who score < 1.8 on the STHS will be
      asked by the applicant to participate in the proposed research. To mitigate potential
      exposure to COVID-19, the only in-person contact with participants throughout the course of
      the proposed study will be during the enrollment process. During enrollment, the applicant
      will explain the study, risks, benefits, voluntary nature of participation, and the patient's
      right to discontinue participation at any time without consequences. Written consent will be
      obtained.

      Data Collection Procedures. Study participants will receive the study package by USPS mail
      two weeks after hospital discharge and will also receive a phone visit at Week 2. Study
      package materials will include a Polar H7 heart rate monitor, ActiGraph wGT3X-BT (to link to
      the Polar monitor for HRV data collection), written instructions for HRV measurement, hard
      copies of questionnaires (to view during the data collection phone call), instructions to
      return the monitors, and a prepaid return envelope. Participants will also be sent a secure
      link via text or email to an instructional video depicting verbal and visual demonstration of
      proper HRV measurement. The applicant will call the participant once a mail delivery notice
      has been received to instruct and confirm proper placement of the monitors used to measure
      HRV and answer any questions. All data collection will occur at Week 2.

      HRV Procedures. At Week 2, participants will be instructed to place the Polar H7 heart rate
      monitor around the center of their chest, in contact with the skin, and the ActiGraph
      wGT3X-BT around their waist, according to directions outlined in the written instructions
      provided and as demonstrated in the instructional video and practiced with the applicant over
      the phone. Participants will be informed that the monitors are used to gather data about
      their body at rest. The Polar H7 heart rate monitor connects to the ActiGraph with Bluetooth®
      wireless technology so that the interval between normal to normal (RR) heart beats can be
      transferred to csv files for analysis. The Polar H7 has demonstrated strong correlation with
      ECG for measuring HRV (r=0.99). The HRV protocol will take place during a 10-minute time
      period on two consecutive days, to ensure at least one timeframe of usable data. Participants
      will be instructed to place the monitors first thing in the morning after they wake up and
      empty their bladder. Once the monitors are placed, participants will be instructed to lay
      supine, still, and quiet for 10 minutes. The standardized HRV protocol enhances reliability
      of the HRV measurement because control of extraneous variables is maintained. Respirations
      will not be controlled because this can artificially increase HF HRV. The gold standard
      amount of time for a short-term HRV recording is 5 minutes. The intermediate 5 minutes of the
      recording will be used for analysis, so that the initial minutes of lying flat and the final
      minutes will be removed. After the participant completes the two HRV measurements, they will
      be asked to return the monitors in a prepaid envelope that will be picked up from their
      mailbox by USPS, mitigating any exposure to COVID-19.

      Phone Visit to Complete Questionnaires. After completion of the HRV measurement instructional
      phone visit, participants will receive their Week 2 data collection visit. Participants in
      Dr. Dunn's study will receive their phone visit from a trained data collector prior to the
      RCT's intervention. Participants in the applicant's study will receive their phone visit from
      the applicant. The data collectors/applicant will follow identical scripts for data
      collection. During the phone visit, the data collector/applicant will first ask how HRV
      measurement went that morning and remind participants to complete the measurement the
      following morning. Participants will then complete four questionnaires. Deidentified HRV data
      will be uploaded into Box, a secure cloud-based storage service, by the applicant. All
      questionnaire and electronic medical record data will be logged directly into REDCap using a
      secure electronic tablet.

      Measures. The following questionnaires will be completed during the data collection phone
      visit. Demographic Questionnaire: Demographics are being collected to describe the sample and
      determine if these variables are confounders. State-Trait Hopelessness Scale (STHS): The STHS
      measures state and trait hopelessness. The scale uses a 4-point Likert-type scale ranging
      from 1 (strongly disagree) to 4 (strongly agree). Item scores are added and divided by the
      number of items to provide a total score for each subscale, ranging in a final score from 1-4
      with higher scores indicating greater levels of hopelessness. In patients with IHD, the scale
      has demonstrated reliability and validity. ENRICHD Social Support Inventory (ESSI): The ESSI
      measures PSS. The ESSI is a 7-item instrument that uses a 5-point Likert-type scale for items
      1-6 ranging from 1 (none of the time) to 5 (all of the time). The 7th item is yes/no. Items
      are summed for a final score with a range from 8-34, higher scores indicate greater levels of
      PSS. The ESSI was found to be valid and reliable in patients with IHD. Patient Health
      Questionnaire 9 (PHQ-9): The PHQ-9 measures depressive symptom severity. The instrument is
      comprised of 9 items that are scored on a Likert-type scale ranging from 0 (not at all) to 3
      (nearly every day). Item scores are summed for a total score ranging from 0-27, higher scores
      indicating greater depressive symptom severity. The PHQ-9 has been validated in patients with
      IHD. Internal reliability and criterion and construct validity have been previously
      established. Depressive symptoms are being measured as a potential covariate because of the
      known association between hopelessness and depression.

      Both a medical record abstraction and the Charlson Comorbidity Index are completed within two
      weeks after the participant's hospital discharge. The medical record abstraction is completed
      to obtain participant clinical characteristics. The Charlson Comorbidity Index is a
      prognostic index of comorbidity. The instrument predicts 1-year mortality based on illness
      severity, reason for admission, and weighted comorbidity score. It is a reliable and valid
      prognostic indicator for in-hospital and 1-year outcomes in patients with IHD.
    

Observational model: Other
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Data will be collected 2 weeks after hospital discharge for an IHD event. Patients who
        provide written-informed consent and enroll will be sent a package with study materials to
        their home and complete a phone visit 2 weeks after hospital discharge. Recruitment and
        enrollment of all patients will take place during patients' hospitalization for an IHD
        event at a large teaching hospital in the Midwestern United States.
      
Keywords: heart rate variability; hopelessness; perceived social support