Vitamin B12 Supplement to Prevent Cognitive Decline

January 26, 2016 updated by: Timothy Kwok, Chinese University of Hong Kong

Background: Older diabetic people are at greater risk of cognitive decline than non-diabetic people. Vitamin B12 deficiency in older people is associated with cognitive impairment and Alzheimer's disease. Vitamin B12 deficiency may therefore contribute to cognitive decline in older diabetic people.

Objective: To determine whether the correction of mild vitamin B12 deficiency in cognitively normal older diabetic people reduces the incidence of cognitive decline.

Design: randomized, double blind, placebo controlled trial Subject: Cognitively normal diabetic outpatients aged 70 years or older with plasma vitamin B12 150-300 pmol/L in medical and family medicine/ general outpatient clinics.

Procedure: After excluding those with clinical manifestations of vitamin B12 deficiency and without family member who can reliably inform on cognitive functioning (personal contact at least once a week), eligible patients will be invited to participate in this clinical trial. After obtaining written consent, research assistant (RA) will record demographic and clinical information from the subjects and perform neuropsychological tests - 1. Clinical dementia rating scale (CDR), 2. neurocognitive test battery (see below) 3. Chinese Mini mental state examination (MMSE), 4. Geriatric depression scale (GDS). Fasting blood will be taken for serum methylmalonic acid (MMA). Those with cognitive impairment and significant comorbidities will be excluded.

264 eligible subjects will be randomly assigned to take either two Vitamin B12 500 microgram or two identical looking placebo tablets once daily for 27 months.

All subjects or family caregivers are reviewed in the research clinic every 12 weeks in which the research assistant performs a pill count and dispenses the trial tablets. At 9 monthly intervals, the subjects will have neurocognitive test battery repeated at research clinic. CDR will be repeated at month 18 and 27. At month 9 and 27, fasting serum MMA and vitamin B12 will be repeated.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

271

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • China
      • Hong Kong, China
        • The Chinese University of Hong Kong

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

70 years to 100 years (Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • >/= 70 years old
  • B12: 150 - 300 pmol/L
  • Caregiver (personal contact at least once a week)

Exclusion Criteria:

  • Dementia
  • Peripheral neuropathy
  • Anaemia (Hb<10 g/dl)
  • Renal failure (creatinine > 150 µmol/L
  • Stroke

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Placebo
Placebo comparator
Dietary supplement: Placebo
2 tablets
Experimental: Vitamin B12
Vitamin B12, 1mg, daily, 27 months
Dietary supplement: Vitamin B12
2 tablets

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Change in Clinical Dementia Rating Scale (CDR)
Time Frame: Change from baseline in CDR at month 9, 18, 27
Change from baseline in CDR at month 9, 18, 27

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Neurocognitive test battery (NTB) score
Time Frame: Change from baseline in NTB score at month 9, 18, 27
NTB including tests of executive funciton, psychomotor speed and memory
Change from baseline in NTB score at month 9, 18, 27
Change in serum homocysteine (µmol/L)
Time Frame: Change from baseline in serum homocysteine at month 9, 27
Change from baseline in serum homocysteine at month 9, 27

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Chinese University of Hong Kong

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

August 1, 2011

Primary Completion (Actual)

January 1, 2016

Study Completion (Actual)

January 1, 2016

Study Registration Dates

First Submitted

May 22, 2015

First Submitted That Met QC Criteria

May 28, 2015

First Posted (Estimate)

May 29, 2015

Study Record Updates

Last Update Posted (Estimate)

January 28, 2016

Last Update Submitted That Met QC Criteria

January 26, 2016

Last Verified

January 1, 2016

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • DM-B12

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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