The Association Between Cognitive Function and Neuropathy in Individuals With Type 2 Diabetes

NCT ID: NCT06857994

Last Updated: 2025-03-19

Basic Information

• Recruitment Status: RECRUITING
• Total Enrollment: 96 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2025-03-10
• Study Completion Date: 2026-04-30

Brief Summary

The goal of this observational study is to evaluate whether individuals with different types of diabetic neuropathy (peripheral and cardiovascular autonomic neuropathy) are at an increased risk of cognitive impairment and to investigate the potential reasons for this association.

The primary research question is: Is diabetic peripheral and cariovascular autonomic neuropathy in type 2 diabetes associated with cognitive decline?

To address this question, the study will include individuals with and without type 2 diabetes. All participants will undergo comprehensive neuropathy assessments, neuropsychological evaluations and blood biomarker analysis. In addition, some individuals will undergo structural and functional brain MRI.

Detailed Description

Type 2 diabetes (T2D) is a chronic disease with complications that affect various organs over time. While certain complications have been well- established for decades, recent research points to the brain as an important site of diabetes-associated damage. This aligns with the growing awareness of the cognitive impact of diabetes. Diabetes is associated with mild to moderate alterations in cognitive functions across diverse age groups and an increased risk of developing dementia. The precise mechanism underlying these associations remains elusive, but some studies suggest that impaired peripheral nerve function correlates with negative cognitive outcomes and may be associated with structural and functional brain changes. Since diabetic neuropathy is one of the most common complications of diabetes, it might contribute to an increased dementia risk.

ASCEND is a clinical descriptive study that aims to evaluate the association between diabetic neuropathy and cognitive function in individuals with type 2 diabetes (compared to controls without diabetes). The study comprises the following visits:

• Screening visit
• Neuropathy assessment and neuropsychological testing visit
• Structural and functional MRI (only a subset of participants)

The neuropathy assessment will include the following measures:

• Peripheral vibration sensation (biothesiometer)
• Cardiovascular autonomic neuropathy (Vagus device) both resting heart rate variability and cardiovascular reflex tests
• Nerve conduction velocity and amplitude of the Sural nerves by DPN-check
• Light touch and pain sensation (10 g monofilament and 40g needle)
• Peripheral small-fiber sympathetic function (Sudoscan device)
• Cold and warm sensation of foot and lower leg

The neuropsychological test will include the following:

• Rey Auditory Verbal Learning Test (RAVLT)
• Trail Making Test (TMT) part A and B
• Symbol Digit Modalities Test (SDMT)
• RBANS Digit Span forward (Version A)
• Wechsler Adult Intelligence Scale III Letter-Number Sequencing test (WAIS-LNS)
• Verbal Fluency test (letters S and D)
• Grooved Pegboard
• Rapid Visual Processing (RVP) test from the Cambridge Neuropsychological Test Automated Battery (CANTAB) using A' (RVP-A) and mean latency for correct responses

Conditions

Peripheral Diabetic Neuropathy; Cardiovascular Autonomic Neuropathy; Cognitive Impairment; Diabetes Type 2

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: CROSS_SECTIONAL

Study Groups

Type 2 Diabetes and No Neuropathy

This group consists of individuals who meet the inclusion and exclusion criteria and have normal peripheral and cardiovascular autonomic nerve function.

No interventions assigned to this group

Type 2 Diabetes with Peripheral Neuropathy

This group consists of individuals who meet the inclusion and exclusion criteria and have peripheral neuropathy and normal cardiovascular autonomic nerve function.

No interventions assigned to this group

Type 2 Diabetes with Cardiovascular Autonomic Neuropathy

This group consists of individuals who meet the inclusion and exclusion criteria and have cardiovascular autonomic neuropathy. They can have a normal or abnormal peripheral nerve test.

No interventions assigned to this group

Controls (No Type 2 Diabetes)

This group consists of individuals who meet the inclusion and exclusion criteria for controls.

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

For individuals with type 2 diabetes:

• Age >= 65 years
• Type 2 Diabetes diagnosis (defined according to the criteria from World Health Organization) for more than 5 years
• BMI <= 35
• Stable diabetes treatment for at least 8 weeks (adjustments of already prescribed insulin doses are accepted)
• Plasma hemoglobin ≥ 8.00 mmol/L (male) or ≥ 6.4 mmol/L (female)
• Speaks and understands Danish (required for the cognitive tests)
• Informed and written consent

For individuals without type 2 diabetes:

• Age ≥ 65 years
• Not diagnosed with T2D diagnosis (defined according to criteria from World Health Organization (WHO))
• Speaks and understands Danish (required for the cognitive tests)
• Informed and written consent

Exclusion Criteria

• Any medical condition which, based on investigators assessment, challenges or hinders participation in cognitive screening, impedes compliance with the study protocol or evaluation of results, including but not limited to psychiatric disorders, neurological disorders, chronic pain disorders etc.
• Significant history of alcoholism or drug/chemical substance abuse as per the investigator's judgement.
• Individuals in active laser treatment for retinopathy, atrial fibrillation, atrial flutter, or pacemakers since these cannot take part in CAN measurements.
• Individuals unable to take part in the MRI because of e.g., metallic objects in the body or severe claustrophobia.
• Individuals who do not wish to be informed about accidental findings by MR.
• Diagnosis of dementia (ICD F00-F03) or participants who have previously been referred to a dementia clinic.
• Severe hypoglycemic events during the past 6 months requiring medical assistance.
• Severe renal insufficiency as eGFR ≤ 30 ml/min/1.73 m2
• Inadequately treated blood pressure at screening defined as repeated resting blood pressure outside the range of 90-150 mmHg for systolic and 50-100 for diastolic.
• Active or recent (≤ 12 months) malignant disease as judged by the investigator.

• Minimum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Rigshospitalet, Denmark

OTHER

Sponsor Role: collaborator

Steno Diabetes Center Copenhagen

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Steno Diabetes Center Copenhagen

Herlev, , Denmark

Site Status: RECRUITING

Countries

Denmark

Central Contacts

Astrid Wiggers, MD, PhD student

Role: CONTACT

astrid.wiggers@regionh.dk

+45 23 29 92 82

Jørgen Rungby, MD, DMSc, Professor

Role: CONTACT

joergen.rungby@regionh.dk

+45 21 68 66 20

Facility Contacts

Astrid Wiggers, MD, PhD student

Role: primary

astrid.wiggers@regionh.dk

+45 23 29 92 82

Other Identifiers

H-24014649

Identifier Type: -

Identifier Source: org_study_id