Mallikarjun Divya N, Malo Palash Kumar, Mensegere Abhishek, Partha Ajith, Sundarakumar Jonas S, Issac Thomas Gregor, Diwakar Latha
Centre for Brain Research, Indian Institute of Science, Bangalore 560012, Karnataka, India.
Brain Commun. 2024 Oct 15;6(5):fcae343. doi: 10.1093/braincomms/fcae343. eCollection 2024.
The relationship between blood levels of homocysteine (HCY), vitamin B12, folic acid and cognitive impairment is inconclusive. Since HCY is an independent risk factor for cardiovascular diseases, understanding its association with Framingham risk score (FRS) may provide insight into the shared underlying mechanism between cardiovascular disease and cognitive impairment. Cross-sectional analyses utilized baseline data from two ongoing longitudinal studies: the Tata Longitudinal Study of Ageing ( = 923), an urban cohort, and Srinivaspura Ageing, NeuroSenescence and COGnition ( = 4239), a rural cohort. The study compared the HCY, vitamin B12 and folic acid levels across cohorts and normal versus mild cognitive impairment (MCI) participants. The association between HCY and cognitive status was established using regression models. Three models were analysed: model 1-unadjusted; model 2-adjusted for age, gender, smoking, alcohol consumption, diet, hypertension, cardiac illness, diabetes; and model 3-adjusted for variables in model 2 plus vitamin B12 and folic acid. Correlation was calculated between HCY and FRS. The urban cohort exhibited a significantly higher level of HCY [median (IQR) (17.70 (10.2) versus 14.70 (9.7); < 0.001)], vitamin B12 (251 (231) versus 219 (138); < 0.001) and folic acid (8.21 (8) versus 5.48 (4); < 0.001) levels compared to rural cohort. HCY, vitamin B12 and folic acid levels did not differ significantly between normal and MCI participants in the urban cohort. In the rural cohort, among the age-gender matched MCI-normal, participants with normal cognition had higher levels of vitamin B12 (≥60 years) [227 (152) versus 217 (175); = 0.03] and folic acid (<60 years) [5.91 (4) versus 5.40 (4); = 0.04] compared to MCI. There was no association between HCY and cognitive status in both the cohorts, but there was a significant positive relationship between vitamin B12 deficiency and Clinical Dementia Rating-Sum of the Boxes (CDR-SOB), as well as folic acid deficiency and CDR-SOB in rural and urban cohorts, respectively, within a specific age group. A significant correlation was observed between FRS and HCY in the rural cohort (r = 0.17, < 0.001), but not in the urban cohort. This study revealed significant differences in HCY, vitamin B12 and folic acid levels between the cohorts. In the rural cohort, participants with MCI had lower vitamin B12 and folic acid levels in a certain age group. Association between HCY and cognitive status was insignificant in both the cohorts. A small significant correlation between FRS and HCY was seen in the rural cohort.
同型半胱氨酸（HCY）、维生素B12、叶酸的血液水平与认知障碍之间的关系尚无定论。由于HCY是心血管疾病的独立危险因素，了解其与弗雷明汉风险评分（FRS）的关联可能有助于深入了解心血管疾病和认知障碍之间共同的潜在机制。横断面分析利用了两项正在进行的纵向研究的基线数据：塔塔衰老纵向研究（n = 923），这是一个城市队列；以及斯里尼瓦斯普拉衰老、神经衰老与认知研究（n = 4239），这是一个农村队列。该研究比较了不同队列以及正常与轻度认知障碍（MCI）参与者之间的HCY、维生素B12和叶酸水平。使用回归模型确定HCY与认知状态之间的关联。分析了三个模型：模型1-未调整；模型2-调整了年龄、性别、吸烟、饮酒、饮食、高血压、心脏病、糖尿病；模型3-在模型2的变量基础上加上维生素B12和叶酸进行调整。计算了HCY与FRS之间的相关性。与农村队列相比，城市队列的HCY[中位数（四分位间距）（17.70（10.2）对14.70（9.7）；P < 0.001）]、维生素B12（251（231）对219（138）；P < 0.001）和叶酸（8.21（8）对5.48（4）；P < 0.001）水平显著更高。城市队列中正常与MCI参与者之间的HCY、维生素B12和叶酸水平无显著差异。在农村队列中，在年龄-性别匹配的MCI-正常人群中，认知正常的参与者在特定年龄组中维生素B12（≥60岁）[227（152）对217（175）；P = 0.03]和叶酸（<60岁）[5.91（4）对5.40（4）；P = 0.04]水平高于MCI参与者。在两个队列中，HCY与认知状态均无关联，但在特定年龄组内，农村和城市队列中分别存在维生素B12缺乏与临床痴呆评定量表-方框总和（CDR-SOB）之间以及叶酸缺乏与CDR-SOB之间的显著正相关关系。在农村队列中观察到FRS与HCY之间存在显著相关性（r = 0.17，P < 0.001），但在城市队列中未观察到。这项研究揭示了不同队列之间HCY、维生素B12和叶酸水平存在显著差异。在农村队列中，MCI参与者在特定年龄组中维生素B12和叶酸水平较低。两个队列中HCY与认知状态之间的关联均不显著。在农村队列中观察到FRS与HCY之间存在小的显著相关性。
