NCT02457507

Brief Summary

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.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
271

participants targeted

Target at P75+ for phase_4

Timeline
Completed

Started Aug 2011

Longer than P75 for phase_4

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

August 1, 2011

Completed
3.8 years until next milestone

First Submitted

Initial submission to the registry

May 22, 2015

Completed
7 days until next milestone

First Posted

Study publicly available on registry

May 29, 2015

Completed
7 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

January 1, 2016

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

January 1, 2016

Completed
Last Updated

January 28, 2016

Status Verified

January 1, 2016

Enrollment Period

4.4 years

First QC Date

May 22, 2015

Last Update Submit

January 26, 2016

Conditions

Cognitive Decline

Outcome Measures

Primary Outcomes (1)

  • Change in Clinical Dementia Rating Scale (CDR)

    Change from baseline in CDR at month 9, 18, 27

Secondary Outcomes (2)

  • Change in Neurocognitive test battery (NTB) score

    Change from baseline in NTB score at month 9, 18, 27

  • Change in serum homocysteine (µmol/L)

    Change from baseline in serum homocysteine at month 9, 27

Study Arms (2)

Vitamin B12

EXPERIMENTAL

Vitamin B12, 1mg, daily, 27 months

Dietary Supplement: Vitamin B12

Placebo

PLACEBO COMPARATOR

Placebo comparator

Dietary Supplement: Placebo

Interventions

Vitamin B12DIETARY_SUPPLEMENT

2 tablets

Vitamin B12
PlaceboDIETARY_SUPPLEMENT

2 tablets

Placebo

Eligibility Criteria

Age70 Years - 100 Years
Sexall
Healthy VolunteersYes
Age GroupsOlder Adult (65+)

You may qualify if:

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

You may not qualify if:

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

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

The Chinese University of Hong Kong

Hong Kong, China

Location

Related Publications (1)

  • Kwok T, Lee J, Ma RC, Wong SY, Kung K, Lam A, Ho CS, Lee V, Harrison J, Lam L. A randomized placebo controlled trial of vitamin B12 supplementation to prevent cognitive decline in older diabetic people with borderline low serum vitamin B12. Clin Nutr. 2017 Dec;36(6):1509-1515. doi: 10.1016/j.clnu.2016.10.018. Epub 2016 Oct 27.

    PMID: 27823800DERIVED

MeSH Terms

Conditions

Cognitive Dysfunction

Interventions

Vitamin B 12

Condition Hierarchy (Ancestors)

Cognition DisordersNeurocognitive DisordersMental Disorders

Intervention Hierarchy (Ancestors)

CorrinoidsTetrapyrrolesPyrrolesAzolesHeterocyclic Compounds, 1-RingHeterocyclic CompoundsHeterocyclic Compounds, 4 or More RingsHeterocyclic Compounds, Fused-RingMacrocyclic CompoundsPolycyclic Compounds

Study Design

Study Type
interventional
Phase
phase 4
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, INVESTIGATOR
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

May 22, 2015

First Posted

May 29, 2015

Study Start

August 1, 2011

Primary Completion

January 1, 2016

Study Completion

January 1, 2016

Last Updated

January 28, 2016

Record last verified: 2016-01

Locations

CN(1)