Comparative Efficacy of Self-Help Multicomponent Lifestyle Medicine Intervention and Cognitive Behavioral Therapy for Depressive Symptoms

The objective of this proposed pilot randomized controlled trial is to examine the efficacy of self-help multicomponent lifestyle medicine intervention and cognitive behavioral therapy relative to a wait-list control group for alleviating depressive symptoms among Hong Kong Chinese adults.

This study will serve as a pioneering attempt to investigate the comparative efficacy of self-help multicomponent lifestyle medicine intervention and cognitive behavioral therapy for reducing depressive symptoms. The proposed study will pave the way for future intervention development and provide the evidence base for the integration of lifestyle-based interventions into the current treatment model.

Prior to all study procedures, eligible participants will be required to complete an online informed consent via an in-house smartphone application, Longitudinax Pro. Around 90 eligible participants aged 18 or above with a Patient Health Questionnaire-9 total score of 10 or higher will be randomly assigned to either self-help multicomponent lifestyle medicine intervention (LM), self-help CBT (CBT), or the waitlist control group (WL) in a ratio of 1:1:1 by an independent statistician. Participants in the LM and CBT groups will receive a booklet-delivered multicomponent lifestyle medicine intervention and CBT for depressive symptoms, respectively. Both interventions comprise 6 weekly 60-minute sessions and daily homework activities according to instructions in the booklet (details can be found in "Arms and Interventions"). For both LM and CBT groups, a follow-up phone call (approximately 15 minutes) will be made every two weeks to encourage participants to adhere to the intervention. Participants in the WL group will be asked to maintain their typical activities during the trial period, and they will be given access to either the booklet-delivered multicomponent lifestyle medicine intervention or booklet-delivered CBT following the 3-month post-intervention follow-up. The primary outcome of interest will be depressive symptoms. The secondary outcomes will include anxiety symptoms, perceived insomnia severity, health-promoting behaviors, quality of life, functional impairment, and intervention evaluation at immediate post-intervention and 3-month follow-up assessments.

Eligibility Criteria:
Inclusion Criteria:

* Hong Kong residents
* Aged 18 or above
* Able to read Chinese and write in Chinese or English
* Have a Patient Health Questionnaire-9 (PHQ-9) total score of 10 or higher indicating at least moderate level of depressive symptoms
* Willing to provide informed consent and comply with the trial protocol
* Have an Internet-enabled mobile device (iOS or Android operating system) (for data collection purposes)

Exclusion Criteria:

* Received psychotherapy for depression and/or insomnia in the past 6 months
* A change in psychotropic drugs or over-the-counter medications that target depression and/or insomnia within 2 weeks before the baseline assessment
* A PHQ-9 item-9 score equal to or higher than 2, indicating a moderate level of suicidal risk that requires active crisis management (referral information to professional mental health services will be provided)
* Currently participating in another interventional study that may potentially improve mental health
* Pregnancy
* Self-disclosure of having unsafe conditions for which physical activity or a change in diet was contraindicated by physicians or other health professionals (e.g., dietitian)
* Self-disclosure of a diagnosis of any major psychiatric, medical, or neurocognitive disorders that make participation unsuitable or interfere with the adherence to the interventions