Vitamin B12 Supplement to Prevent Cognitive Decline
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 271
- 试验地点
- 1
- 主要终点
- Change in Clinical Dementia Rating Scale (CDR)
研究概览
简要总结
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 70 Years 至 100 Years（Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •>/= 70 years old
- •B12: 150 - 300 pmol/L
- •Caregiver (personal contact at least once a week)
排除标准
- •Peripheral neuropathy
- •Anaemia (Hb<10 g/dl)
- •Renal failure (creatinine > 150 µmol/L
结局指标
主要结局
Change in Clinical Dementia Rating Scale (CDR)
时间窗: Change from baseline in CDR at month 9, 18, 27
次要结局
- Change in serum homocysteine (µmol/L)(Change from baseline in serum homocysteine at month 9, 27)
- Change in Neurocognitive test battery (NTB) score(Change from baseline in NTB score at month 9, 18, 27)
研究者
Timothy Kwok
Professor
Chinese University of Hong Kong