Objective Vascular Biomarkers as Triage for Depression in Chronic Atrophic Gastritis

Depressive symptoms are highly prevalent in patients with chronic atrophic gastritis (CAG) but are frequently under-detected due to stigma and reliance on subjective questionnaires. This multicenter, cross-sectional observational study aims to validate a novel clinical triage workflow. It repurposes routine vascular assessments (specifically dorsalis pedis artery ultrasound and arterial stiffness metrics) as objective "biological entry points" to facilitate mental health referrals. The study will enroll approximately 450-520 adults with histologically confirmed CAG across four clinical centers in China. The primary objective is to determine the diagnostic accuracy of these vascular biomarkers for identifying patients with moderate-to-severe depressive symptoms (PHQ-9 score \>= 10). Secondary objectives include evaluating the implementation feasibility (e.g., referral uptake, screening completion rate) of this integrated care model in routine gastroenterology practice.