Effects of Olfactory Training on the Brain Function in T2DM Patients With Mild Cognitive Impairment

NCT06327633 | Completed

• 1 other identifier: ZZ2024
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This is a prospective, randomized, open label, parallel, 4-month study to explore and evaluate the therapeutic effects of olfactory training on the cognitive function, olfactory function, and odor-induced brain activation in T2DM patients with mild cognitive impairment (MCI).

Conditions

Type 2 Diabetes Mellitus; Mild Cognitive Impairment

Keywords

Functional MRI; Cognition; Olfactory training

Outcome Measures

Primary Outcomes (1)

• Change of cognitive function (evaluated by MoCA score)

  Whether MoCA scores in the two groups of Type 2 diabetes mellitus patients with MCI after intervention were different from those before treatment and the difference of changes between the two groups. The MoCA scale evaluates overall cognitive function, with a total score of 30. Generally, subjects scoring ≥26 points are considered as normal cognition, while between 19-25 points as mild cognitive impairment. An extra point is added If the subject has less than 12 years of education.

  from baseline to 4-month follow-up

Secondary Outcomes (3)

• Change of olfactory brain activation by fMRI

  from baseline to 4-month follow-up

• Change of Olfactory function

  from baseline to 4-month follow-up

• Change of metabolism

  from baseline to 4-month follow-up

Study Arms (2)

Olfactory Training Group

EXPERIMENTAL

The subjects repeatedly sniffed pleasant scents of rose, lemon, clove, eucalyptus, coffee and cinnamon twice a day, 6-min per time, with focus, until the completion of the study. Meanwhile, all patients will also continue on their existing dose and regimen of glucose- lowering schemes throughout the study. Twice weekly phone calls will be performed to evaluate the blood glucose situation, assess the safety of intervention and confirm the compliance of participants.

Other: Olfactory Training

Control Group

NO INTERVENTION

The subjects will maintain the original diet and lifestyle, and also continue on their existing dose and regimen of glucose- lowering schemes throughout the study. Phone calls will be made to evaluate the blood glucose situation.

Interventions

Olfactory Training OTHER

The subjects repeatedly sniffed pleasant scents of rose, lemon, clove, eucalyptus, coffee and cinnamon twice a day, 6-min per time, with focus, until the completion of the study.

Olfactory Training Group

Eligibility Criteria

• Age: 40 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• patients with type 2 diabetes mellitus;
• Aged: 40 -75 years ;
• Cognitive function assessment suggests mild cognitive impairment;
• A stable glucose-lowering regimen for more than 2 months;
• ≥6 years of education;
• Right-handed.

You may not qualify if:

• Cognitive function assessment suggests normal cognition or dementia;
• Other dementia related neurological diseases or depression, Mental dysplasia, mania, schizophrenia, etc in the past 2 years; Central nervous system diseases, including brain trauma, intracranial hemorrhage, acute cerebral infarction, etc;
• Severe sinusitis, nasal cavity and sinus polyps, skull base or nasopharyngeal tumors and other space occupying lesions;
• Congenital diseases and traumatic history of nose, maxillofacial and skull base affecting olfaction.
• With symptoms of upper respiratory tract infection, including nasal congestion, runny nose, fever, etc. on the day of MR examination;
• Diabetic Acute and chronic complications, including diabetic ketoacidosis, diabetic ketoacidosis; a hyperglycemic hyperosmolar state or severe hypoglycemic coma, etc.
• Severe impairment of heart, liver, kidney and other organs;
• Contraindications of MRI examination, such as implantation of metal prosthesis in vivo, claustrophobia, etc;
• Pregnant and lactating women;
• Receive other test drugs currently or within 3 months before participating in the project;
• Known or suspected allergic history to essential oil;
• Taking cognitive-related drugs.

Sponsors & Collaborators

• The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School: lead

Study Sites (1)

Division of Endocrinology, the Affiliated Drum Tower Hospital of Nanjing University

Nanjing, Jiangsu, 210008, China

Location

Related Publications (2)

• Zhang Z, Zhang B, Wang X, Zhang X, Yang QX, Qing Z, Lu J, Bi Y, Zhu D. Altered Odor-Induced Brain Activity as an Early Manifestation of Cognitive Decline in Patients With Type 2 Diabetes. Diabetes. 2018 May;67(5):994-1006. doi: 10.2337/db17-1274. Epub 2018 Mar 2.

  PMID: 29500313 RESULT

• Zhang Z, Zhang B, Wang X, Zhang X, Yang QX, Qing Z, Zhang W, Zhu D, Bi Y. Olfactory Dysfunction Mediates Adiposity in Cognitive Impairment of Type 2 Diabetes: Insights From Clinical and Functional Neuroimaging Studies. Diabetes Care. 2019 Jul;42(7):1274-1283. doi: 10.2337/dc18-2584. Epub 2019 May 21.

  PMID: 31221697 RESULT

MeSH Terms

Conditions

Diabetes Mellitus, Type 2; Cognitive Dysfunction

Interventions

Olfactory Training

Condition Hierarchy (Ancestors)

Diabetes Mellitus; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Cognition Disorders; Neurocognitive Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Therapeutics

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 18, 2024
• First Posted: March 25, 2024
• Study Start: January 1, 2024
• Primary Completion: May 15, 2025
• Study Completion: May 15, 2025
• Last Updated: July 11, 2025

Record last verified: 2024-01

Locations

CN (1)