The Effects and Neural Mechanisms of Vitamin D and Iron-Immune Homeostasis on Inhibitory Control in Obsessive-Compulsive Disorder

NCT07763977 | Enrolling By Invitation

• 1 other identifier: KY2025-1212-01
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This study is a randomized, open-labled, no-treatment-controlled clinical trial designed to investigate the effects of vitamin D and iron-immune homeostasis on inhibitory control and the underlying neural mechanisms in patients with obsessive-compulsive disorder (OCD). Participants will be patients with OCD who meet the study eligibility criteria. The study's primary aim is to compare changes in glutamate and related metabolite concentrations within the anterior cingulate-thalamic circuit, inhibitory control performance, peripheral immune markers, and clinical symptoms before and after treatment with calcitriol and iron polysaccharide complex. The study will also investigate the neural-circuit mechanisms underlying inhibitory control deficits in patients with OCD and their changes following the interventions. These objectives will be addressed using resting-state Magnetic Resonance Spectroscopy(MRS), inhibitory control tasks, peripheral blood immune-marker measurements, and clinical symptom assessments. The primary hypothesis is that inhibitory control deficits in patients with OCD are associated with dysregulated glutamatergic metabolism in the anterior cingulate-thalamic circuit. Vitamin D and iron supplementation are hypothesized to promote the balance of glutamate and related metabolites within this circuit, regulate immune homeostasis, and improve inhibitory control deficits in patients with OCD.

Conditions

Obsessive Compulsive Disorder (OCD)

Keywords

Obsessive Compulsive Disorder(OCD); Vitamin D; Iron-Immune Homeostasis

Outcome Measures

Primary Outcomes (2)

• Change from Baseline in Neurometabolite Concentrations in Key Brain Regions

  Change from baseline to Week 12 in the concentrations of Glutamate (Glu), Glutamate+Glutamine (Glx), and Glutathione (GSH) within two pre-specified regions of interest: the thalamus and the anterior cingulate cortex (ACC). Levels are measured in both resting and functional states using Magnetic Resonance Spectroscopy (MRS).

  Baseline, Post-treatment (Week 12)

• Change from Baseline in Inhibitory Control Performance

  Change from baseline to Week 12 in inhibitory control performance, as measured by the error rate on a Go-Nogo task.

  Baseline, Post-treatment (Week 12)

Study Arms (2)

Two-drugs group

EXPERIMENTAL

The arm will use calcitriol and iron supplements

Drug: Calcitriol and Iron Supplements

Blank Control Group

NO INTERVENTION

Interventions

Calcitriol and Iron Supplements DRUG

In addition to participants' existing medication regimens, calcitriol and iron supplements will be added.

Two-drugs group

Eligibility Criteria

• Age: 14 Years - 45 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Meet the DSM-5 diagnostic criteria for obsessive-compulsive disorder (OCD);
• Have a total score of ≥16 on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and a total score of \<17 on the 17-item Hamilton Depression Rating Scale (HAMD-17);
• Have a disease duration of ≥1 year and be between 14 and 50 years of age;
• Be right-handed and have completed at least junior high school education; and
• Fully understand the study procedures, be willing and able to participate in and complete the entire study, and provide written informed consent.

You may not qualify if:

• Presence of a neurological disorder or serious medical condition;
• Pregnancy or breastfeeding;
• A history of alcohol or substance abuse or dependence;
• A history of seizures;
• A diagnosis of a major psychotic disorder or bipolar disorder;
• A diagnosis of depressive disorder;
• Any contraindication to magnetic resonance imaging (MRI);
• Use of iron or vitamin D supplements within the previous 6 months, or use of corticosteroids for any reason within the previous 3 months; or
• Presence of an acute or chronic systemic disease that may affect iron or vitamin D levels, including, but not limited to, hypothyroidism, hyperthyroidism, hypoparathyroidism, hyperparathyroidism, diabetes mellitus, clinically active infection, or iron-deficiency anemia.

Sponsors & Collaborators

• Guangdong Provincial People's Hospital: lead

Study Sites (1)

Guangdong Mental Health Center, Guangdong Provincial People's Hospital

Guangzhou, Guangdong, 510120, China

Location

MeSH Terms

Conditions

Obsessive-Compulsive Disorder

Interventions

Calcitriol; Iron-Dextran Complex

Condition Hierarchy (Ancestors)

Anxiety Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Dihydroxycholecalciferols; Hydroxycholecalciferols; Cholecalciferol; Cholestenes; Cholestanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Sterols; Vitamin D; Secosteroids; Membrane Lipids; Lipids; Coordination Complexes; Organic Chemicals; Dextrans; Glucans; Polysaccharides; Carbohydrates

Study Officials

• Huirong Zheng, MD

  Guangdong Provincial People's Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Director

Study Record Dates

• First Submitted: August 9, 2026
• First Posted: August 13, 2026
• Study Start: August 6, 2024
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): June 30, 2027
• Last Updated: August 13, 2026

Record last verified: 2026-08

Locations

CN (1)