Efficacy of a Culturally-adapted Mediterranean Diet Intervention on Depression in Relation to the Gut Microbiome: A Randomised Controlled Trial Using the Experience Sampling Methodology
Overview
- Phase
- Not Applicable
- Status
- Not yet recruiting
- Enrollment
- 90
- Locations
- 1
- Primary Endpoint
- Change in the Patient Health Questionnaire-9 (PHQ-9)
Overview
Brief Summary
The objective of this study is to investigate the efficacy of a culturally-adapted Mediterranean diet, in accordance with clinical guidelines and research evidence, in reducing depressive symptoms among Hong Kong Chinese adults. Additionally, this study will also explore the potential underlying role of the gut microbiome in the relationship between the Mediterranean diet and depression. This study serves as a pioneering attempt to examine the efficacy and intervention acceptability of a culturally-adapted Mediterranean diet in managing depressive symptoms.
Several studies have demonstrated the relationship between diet and mood, while existing studies suggest that consistently adhering to the Mediterranean diet may yield a more pronounced antidepressant effect. Considering that depression is often associated with low motivation, dietary interventions that require active participation may encounter implementation challenges and potentially impact the adherence rate. To address this issue, our study proposes using ecological momentary assessment (EMA), which involves sending frequent reminders to participants, allowing us to examine diet quality and adherence as well as changes in depressive symptoms at various time points. This approach also minimizes potential recall bias and enhances data collection accuracy. If the hypothesis is supported, dietary intervention could emerge as a promising therapeutic strategy for alleviating depressive symptoms. Furthermore, this study could provide insights into the role of the gut microbiome as a potential underlying mechanism between diet and depressive symptoms. The findings could have significant implications for clinical practice.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Single (Outcomes Assessor)
Eligibility Criteria
- Ages
- 18 Years to 65 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Hong Kong residents aged 18-65 years;
- •Able to read Chinese and type in Chinese or English;
- •Have a Patient Health Questionnaire-9 (PHQ-9) score of 10 or higher, indicating at least a moderate level of depressive symptoms;
- •Meet the Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic criteria for current MDD according to the Mini International Neuropsychiatric Interview (MINI);
- •Have a Mediterranean Diet Index (KIDMED 2.0) score less than 3, indicating very-low-quality diet;
- •Possess an Internet-enabled iOS- or Android-operated mobile device; and
- •Willing to provide informed consent and comply with the trial protocol.
Exclusion Criteria
- •The presence of other current psychiatric disorders as assessed by the MINI (bipolar disorder, posttraumatic stress disorder, personality disorders, eating disorders, psychotic disorders, or substance abuse disorder);
- •Have a medical condition or neurocognitive disorder that may prevent dietary changes as recommended by physicians or dietitians;
- •Current serious suicidal risk (non-fleeting intent or plan) as assessed by a PHQ-9 Item 9 score \>2 (referral information to professional mental health services will be provided);
- •Involvement in dietary changes (self-initiated/supervised by professionals) in the past 2 weeks;
- •Involvement in any psychological treatment specifically for depression in the past 6 months;
- •A change in medication within 2 weeks prior to the baseline assessment/during the study;
- •Pregnancy and hospitalization;
- •Current participation in any other trial(s); and
- •Unwilling to change their diet if being allocated to the MediDiet group or food allergies or intolerances preventing diet adherence (specifically allergies to seafood, soy, nuts, yogurt, or dairy products).
Arms & Interventions
Mediterranean diet (MediDiet) group
Participants in MediDiet group will receive a culturally adapted Mediterranean diet prepared by the research team on a daily basis. This diet is designed by a certified dietitian based on clinical guidelines and research evidence. Participants will follow the intervention for a duration of four consecutive weeks.
Intervention: Mediterranean Diet (Dietary Supplement)
Care-as-usual (CAU) group
Participants in the CAU group will be instructed to maintain their usual dietary habits throughout the study period and will not receive any specially prepared Mediterranean diet from the research team. In addition, they will have access to care based on their needs and preferences, such as pharmacological interventions, psychological interventions, and complementary and alternative medicine. An intervention tracking log will be used to monitor the care the participants received to prevent violations of the study protocol. The CAU group will be given lifestyle-based self-help materials after the completion of follow-up assessments.
Outcomes
Primary Outcomes
Change in the Patient Health Questionnaire-9 (PHQ-9)
Time Frame: Baseline, immediate post-intervention, and 12-week follow-up
The PHQ-9 is a 9-item questionnaire used for screening, diagnosing, monitoring and measuring the severity of depression, which scores each of the nine DSM-IV criteria from "0" (not at all) to "3" (nearly every day).
Secondary Outcomes
- Change in the adapted version of the Modified Mediterranean Diet Score (ModiMedDiet Score)(Baseline, immediate post-intervention, and 12-week follow-up)
- Change in the Generalized Anxiety Disorder 7-item Scale (GAD-7)(Baseline, immediate post-intervention, and 12-week follow-up)
- Change in the Insomnia Severity Index (ISI)(Baseline, immediate post-intervention, and 12-week follow-up)
- Change in the Seven-day Food Record (7dFR)(Baseline, immediate post-intervention, and 12-week follow-up)
- Change in the International Physical Activities Questionnaire-Chinese version (IPAQ-C)(Baseline, immediate post-intervention, and 12-week follow-up)
- Change in the Short Form (Six-Dimension) Health Survey (SF-6D)(Baseline, immediate post-intervention, and 12-week follow-up)
- Change in the Sheehan Disability Scale (SDS)(Baseline, immediate post-intervention, and 12-week follow-up)
- Change in the Treatment Acceptability Scale (TAS)(Baseline and immediate post-intervention)
- Change in the Credibility-Expectancy Questionnaire (CEQ)(Baseline and immediate post-intervention)
- Change in gut microbiome(Baseline and immediate post-intervention)
- Self-developed Survey(Baseline)
Investigators
Fiona YY Ho
Associate Professor
Chinese University of Hong Kong