Mindfulness & Stress Management Study for Cardiac Patients

Objectives:

The objective of this feasibility study is to conduct a pilot randomized controlled trial (RCT) of Mindfulness-Based Stress Reduction (MBSR) versus usual care in CR-eligible cardiac patients. Randomization will be stratified within two strata based on participation in CR (yes/no) among CR-eligible patients. The primary goals of this pilot study are to: 1) obtain estimates of treatment effects and variability; 2) evaluate recruitment and retention strategies; and 3) examine the safety of the MBSR protocol in CR-eligible patients.

Design and Outcomes:

The study design is a randomized controlled trial with randomization in two strata. The primary outcome will be a change (improvement) in heart rate variability (HRV) as assessed by a 24-hour Holter monitor worn by patients three times throughout the study: (pre- and post-intervention and 9-month follow-up). Time domain variables SDNN (the standard deviation of R-to-R intervals and RMSSD (the root mean square of successive differences in adjacent R-to-R intervals will be assessed. Time domain variables will be assessed via 24-hour Holter monitoring at baseline, 3-month follow-up and 9-month follow-up. HRV is a well-established method to assess the autonomic nervous system. Secondary outcomes will include psychosocial measures (depressive symptoms, mentally unhealthy days, stress, and anxiety) as well as cardiovascular risk factors (systolic blood pressure, body mass index, high density lipoprotein cholesterol, triglycerides, hemoglobin A1C, and c-reactive protein). All participants will undergo a baseline assessment, followed by randomization to the treatment or control condition, and three follow-up assessments, at 3, 6, and 9 months after randomization. The 3-month follow-up will occur immediately post-intervention and the 9-month follow up will occur 6-months post-intervention. The baseline, 3-month and 9-month (final) follow-up assessments will be in-person and will include questionnaires on stress and emotions, quality of life, a short physical performance battery, a blood draw to assess lipids, high sensitivity C-Reactive Protein and hemoglobin A1c as well as the 24-hour Holter monitor to assess HRV. The 6-month follow-up assessment will be by telephone only and include brief assessments of moods, stress, and symptoms. The investigators anticipate the pilot study will be completed in 18 months.

Interventions and Duration:

Upon enrollment, participants will be randomized into two groups, the intervention group (MBSR) or the control group (no MBSR). Randomization will occur separately for those enrolled in CR and those not enrolled in CR. For those in the stratum that attends CR, the control condition will consist of CR only and usual care, whereas for participants in the stratum that does not attend CR, the control condition will consist of usual care. All participants in both strata will received standard printed materials on healthy lifestyles and stress management. The intervention lasts for 8 weeks and will occur within the first 12 weeks (3 months) after randomization. The standard outpatient Phase II CR program offered within the Fairview Hospital system is a traditional exercise-based program that includes an intake visit and up to 24 1-hour monitored exercise sessions (1-3 times per week for 8-24 weeks, individualized to patient needs and therapy goals) and up to 8 or 9 1-hour educational sessions. Patients participating in CR who are randomized to the intervention group will participate in the same standard outpatient Phase II CR as those individuals randomized to the control condition within this stratum, plus an 8-week MBSR course. The MBSR course is taught per a standard protocol in a group setting and consists of eight 2.5-hour weekly sessions and one 6.5-hour retreat; the MBSR course will be led by trained facilitators from the University of Minnesota Center for Spirituality and Healing.

Sample Size and Population:

The targeted enrollment is 48 participants, with 32 randomized to participate in MBSR across the two strata and 16 randomized to the control condition (no MBSR) who will receive usual care (this includes CR for those who have opted to enroll in CR). The investigators will recruit CR-eligible cardiac patients from three sites within the Fairview Hospital system that offer CR (Ridges in Burnsville, Southdale in Edina, and University of Minnesota Riverside Campus in Minneapolis), as well as through electronic health records, clinic visits with health care providers, advertisement and flyers located at clinics and the CR locations, and inclusion of the study on www.studyfinder.umn.edu.