This study aims to investigate the etiology of anxiety, depression, and panic disorders, providing new evidence and insights into the root causes and effective treatments, potentially offering a novel approach to achieving complete recovery.

Background: Anxiety, depression and panic disorders are among the most prevalent mental health conditions globally, affecting millions and imposing a substantial burden on individuals, families, and healthcare systems. These disorders often manifest through recurrent, severe episodes of anxiety and fear, frequently accompanied by physical symptoms such as palpitations, chest pain, and dizziness, which can lead to significant functional impairment and diminished quality of life. While current treatment options include pharmacotherapy and cognitive-behavioral therapy, response rates vary, and many patients experience residual symptoms or adverse effects, leading to high rates of treatment discontinuation. Furthermore, the growing recognition of treatment-resistant anxiety, depression and panic disorders highlights an urgent need for innovative, evidence-based therapies that provide sustained relief without compromising safety.

Introduction Anxiety, depression and panic disorders are pervasive and debilitating chronic mental health conditions, affecting approximately 20% of the global population over a lifetime. Characterized by episodes of intense fear and physical symptoms such as heart palpitations, shortness of breath, and dizziness, these disorders can severely impact daily functioning, interpersonal relationships, and overall quality of life. Individuals with these conditions are also at increased risk for comorbidities including depression, substance use disorders, and cardiovascular disease, further complicating their clinical profile and necessitating more comprehensive treatment strategies.

Despite the availability of pharmacotherapy, such as selective serotonin reuptake inhibitors (SSRIs) and benzodiazepines, alongside cognitive-behavioral therapy (CBT), there remain substantial challenges in achieving and maintaining symptom relief. Response rates vary widely, and a significant proportion of patients experience partial or inadequate relief, with some exhibiting treatment-resistant symptoms. Moreover, pharmacological treatments can be associated with side effects like weight gain, fatigue, and cognitive impairment, which may lead to discontinuation or non-adherence. These limitations highlight a critical need for alternative or adjunctive interventions that can provide more effective, sustainable, and safer outcomes.

This trial was therefore designed to assess the prevalence of pathogenic gut bacteria among patients with anxiety, depression, and panic disorder compared to healthy controls.

Objective: This study aims to investigate the etiology of anxiety, depression, and panic disorders, providing new evidence and insights into the root causes, potentially offering a novel approach to these conditions..

Findings from this study are anticipated to advance clinical understanding and treatment options for anxiety, depression and panic disorders, providing a potentially more effective approach and that provide lasting relief for patients struggling with these conditions.

Inclusion Criteria:

• • Adults aged 18-65 years.

  • Either of the following:

    1. Diagnosed with anxiety, depression, or panic disorder according to DSM-5 criteria, regardless of current treatment status.
    2. Healthy individuals with no history of psychiatric disorders (control group).

  • Able to provide informed consent and stool sample.

Exclusion Criteria:

• • Diagnosis of psychotic disorders or neurocognitive conditions.

  • Use of systemic antibiotics or antifungals within the past 60 days.

The study population will consist of adult males and females aged 18 to 65 recruited from the general population and outpatient mental health clinics. Participants will include individuals with clinically confirmed anxiety, depression, or panic disorder, as well as healthy control subjects with no psychiatric history. The study will aim to include participants from diverse ethnic and cultural backgrounds to ensure broad representation of the population.

Individual participant data will not be shared due to privacy considerations and data governance restrictions related to identifiable microbiome and psychological data. Summary results and aggregated findings will be made publicly available through publication and ClinicalTrials.gov reporting.