Behavior, Biology and Well-Being Study

The central aim of this pilot study is to compare markers of inflammation and gut microbial diversity with users of the Healthy Minds Program (HMP) app, an intervention designed to promote well-being. The investigators plan to conduct a randomized controlled trial (RCT) involving 300 participants comparing 4-weeks of the HMP app with an active control (Psychoeducation \[HMP without meditation practice\]), and a waitlist control in a sample of United States adults with elevated depression symptoms.

Depression is highly prevalent and associated with extreme personal and societal costs. Meditation training reduces depression symptoms and psychological distress, but access to in-person programs is limited due to associated cost and lack of available services. Research on neurocognitive and biological mechanisms of mediation training in alleviating depression is at a preliminary stage, and an obstacle limiting research progress is over-reliance on retrospective self-report measures, which are vulnerable to a host of biases. This project will use gold-standard behavioral measures and explore novel measures of relevant neurocognitive and behavioral processes, namely pattern separation, self-referential thought, and video-based assessment of emotional well-being. Furthermore, the project will investigate effects on the gut microbiome (with fecal samples) and inflammation (with dried blood spots), which reflect biological systems hypothesized to be mechanistically related to benefits of meditation and well-being training.

Specific Aims:

* Aim 1. Determine the feasibility and acceptability of assessing inflammatory activity and gut microbiome within the context of a fully remote randomized controlled trial (RCT). Participants with elevated depression symptoms from an RCT (n = 1,100; registered to NCT05183867) comparing the Healthy Minds Program (HMP) app with an active control (HMP with didactic content only) and wait-list will be invited to provide dried blood spots (DBS) for inflammatory protein analysis and fecal samples for gut microbial analysis at baseline and 3-month follow-up. Hypotheses: It will be feasible to recruit 300 participants to provide DBS and fecal samples and 80% will provide samples at both time points (completer n = 240) with no differences in completion rates between non-Hispanic White and racial/ethnic minority participants.
* Aim 2. Characterize the association between self-reports of well-being, inflammatory activity at baseline, and microbiota diversity at baseline. Hypotheses: Well-being will correlate inversely with both protein biomarkers of inflammation (CRP, IL-6) and mRNA-derived indicators of pro-inflammatory transcriptional activity. Well-being will correlate positively with alpha diversity of the gut microbiome. These associations will not be moderated by participant race/ethnicity.
* Aim 3. Evaluate intervention effects on inflammatory activity and microbiota diversity. Hypotheses: Participants randomized to HMP or the active control will show larger reductions in inflammation vs. wait-list at 3-month follow-up and larger increases in alpha diversity of the gut microbiome vs. wait-list at 3-month follow-up. HMP will show larger reductions in inflammation vs. active control at 3-month follow-up and larger increases in alpha diversity vs. active control at 3-month follow-up.

Eligibility Criteria:
Inclusion Criteria:

* Elevated PHQ-8 or PHQ-9 ≥ 5 at screening and pre-baseline interview
* Proficient in English
* Able to provide informed consent
* Have access to a smartphone that can download apps from Google Play or the Apple App Store
* For payment purposes, must be a US citizen or a permanent US resident

Exclusion Criteria:

* Regular daily meditation practice for past 6 months or regular weekly meditation practice for past 12 months
* Attended a meditation retreat or a yoga/body practice retreat with a significant meditation component

  - Previous use of Healthy Minds Program app
* Current suicidal intent and/or high self-injury risk (determined from the interview)
* Self-reported history of psychosis
* Self-reported history of mania
* Current psychopathology that interferes with study participation as assessed by interview
* Living or traveling outside the US during the whole study participation period (trips outside US after the interview phase is not an exclusion)
* Alcohol Use Disorders Identification Test (AUDIT) score ≥ 13 for women and AUDIT score ≥ 15 for men
* Drug Use Disorders Identification Test (DUDIT) score ≥ 8 for women and men