Utilizing portable functional near-infrared spectroscopy to assess improvements in depression after receiving a multi-intervention program for stroke patients in Vietnam: a randomized controlled trial

This study assessed the effectiveness of functional near-infrared spectroscopy (fNIRS) in evaluating post-stroke depression after a six-month multi-intervention program. Ninety-two stroke survivors were randomly assigned to either an experimental group (receiving Motivational Interviewing (MI) and Home Rehabilitation) or a control group (Standard Care). Oxyhemoglobin (HbO₂) levels in the prefrontal cortex were measured using a 48-channel fNIRS system during a cognitive task at baseline, three months, and six months. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). Data were analyzed using the General Linear Model (GLM) and Receiver Operating Characteristic (ROC) curve analysis. The experimental group showed significant improvements in depressive symptoms, along with corresponding changes in HbO₂ levels in the left orbitofrontal cortex (OFC). The optimal HbO₂ cutoff for predicting depression was −0.47 mmol·mm in the left OFC for the experimental group, −0.07 mmol·mm in the ventrolateral prefrontal cortex (VPC), and 0.29 mmol·mm in the frontopolar prefrontal cortex (FPC) for the control group.