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

Type 2 Diabetes Mellitus Clinical Trial

Official title:

A Pilot, 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.

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06327633
• Other study ID #: ZZ2024
• Status: Recruiting
• Phase: N/A
• Start date: January 1, 2024
• Est. completion date: August 1, 2024

Study information

• Verified date: January 2024
• Source: The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This is a pilot, 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).

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 40
• Est. completion date: August 1, 2024
• Est. primary completion date: August 1, 2024
• Accepts healthy volunteers: No
• Gender: All
• Age group: 40 Years to 75 Years

Eligibility

Inclusion Criteria:

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

Exclusion Criteria:

• 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.

Related Conditions & MeSH terms

• Cognitive Dysfunction
• Diabetes Mellitus, Type 2
• Mild Cognitive Impairment
• Type 2 Diabetes Mellitus

Intervention

Other:
• Olfactory Training
The subjects repeatedly sniffed pleasant scents of rose, lemon, clove, eucalyptus, coffee and cinnamon twice a day, 5-min per time, with focus, until the completion of the study.

Locations

Country	Name	City	State
China	Division of Endocrinology, the Affiliated Drum Tower Hospital of Nanjing University	Nanjing	Jiangsu

Sponsors (1)

Lead Sponsor	Collaborator
The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School

Country where clinical trial is conducted

China, 

References & 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 201 — View Citation

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):1274-1 — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change of olfactory brain activation by fMRI	Whether the activation degree of olfactory task fMRI brain area in the two groups after intervention was different from that before treatment and the difference of changes between the two groups. All patients underwent odor-induced task fMRI on a 3.0T MR scanner with 222 volumes for task fMRI and 230 volumes for resting-state fMRI. The odor-induced task consisted of "fresh air" "rest" and "scent". Odor-induced brain activation was assessed by a general linear model using Statistical Parametric Mapping 12 (SPM12) software. Following extraction of the three separate conditions "fresh air," "scent," and "rest" from the whole sequence, contrasts were made for each participant between "fresh air > rest" and "scent > rest." Odor-induced fMRI data were analyzed in the mask of the olfactory network, including the regions of bilateral parahippocampus, amygdala, piriform cortex, insula, orbitofrontal cortex, hippocampus, and entorhinal cortices.	from baseline to 4-month follow-up
Secondary	Change of cognitive function	Type 2 diabetes mellitus patients with MCI were relieved of mild cognitive impairment , which means MoCA scores were not less than 26 points after treatment, or improved referring to the MoCA score or the RBANS total score increased by 0.5 standard deviation compared with baseline after treatment.	from baseline to 4-month follow-up
Secondary	Olfactory threshold test	Whether the olfactory threshold scores of the two groups after intervention were higher than those before treatment and the difference of changes between the two groups. Olfactory testing was performed using Olfactory Function Assessment by Computerized Testing (OLFACT) (Osmic Enterprises, Inc.). Based on the University of Pennsylvania Smell Identification Test (UPSIT), OLFACT tests were computerized, standardized, and self-administered. Higher scores indicated better ability to detect odors. Threshold testing was performed by a series of binary dilutions of n- butanol solution in light mineral oil, and scores ranged from 1 to 13.5.	from baseline to 4-month follow-up
Secondary	Change of metabolism	The changes of glycosylated hemoglobin among the two groups before and after intervention. The level of glycosylated hemoglobin <7% means better glucose metabolism.	from baseline to 4-month follow-up