Department of Epidemiology and Biostatistics, School of Public Health, Tianjin Medical University, Tianjin, China.
Tianjin Key Laboratory of Environment, Nutrition and Public Health, Center for International Collaborative Research on Environment, Nutrition and Public Health, Tianjin, China.
Dement Geriatr Cogn Disord. 2019;48(1-2):56-67. doi: 10.1159/000501958. Epub 2019 Aug 22.
Leukocyte telomere length (LTL) is associated with the aging process and age-related degenerative diseases. The relation of peripheral blood LTL to mild cognitive impairment (MCI) and Alzheimer's disease (AD) and the role of folate and homocysteine (Hcy) in this relation remain unclear.
We aimed to investigate the association between LTL and the risks of MCI/AD, and to explore whether folate and Hcy may play a role in this association.
This case-control study included 129 MCI subjects, 131 AD patients and 134 healthy controls. LTL was assessed using real-time polymerase chain reaction assay. Serum folate levels were tested by chemiluminescence enzyme immunoassay, and serum Hcy levels were measured using the enzymatic cycling method. Data were analyzed using multivariate logistic regression and multivariable linear regression with adjustment for potential confounders.
The mean LTL was 1.56 ± 0.25 in controls, 1.44 ± 0.23 in MCI, and 1.28 ± 0.28 in AD patients (p< 0.01). In multivariate logistic regression, subjects in the longest LTL tertile had lower OR for MCI (OR 0.246; 95% CI 0.101-0.597) and AD (OR 0.123; 95% CI 0.044-0.345) in comparison to subjects in the shortest tertile. Shorter LTL was dose-dependently related to the ORs of MCI and AD. Further, serum folate concentration was positively associated with LTL (p < 0.01), while serum Hcy level was negatively associated with LTL (p < 0.05). In stratified analyses, LTL-MCI/AD association varied by serum folate and Hcy level.
Shorter LTL is associated with the risks of MCI/AD. Folate and Hcy might play an important role in this association.
白细胞端粒长度（LTL）与衰老过程和与年龄相关的退行性疾病有关。外周血 LTL 与轻度认知障碍（MCI）和阿尔茨海默病（AD）的关系以及叶酸和同型半胱氨酸（Hcy）在这种关系中的作用尚不清楚。
我们旨在研究 LTL 与 MCI/AD 风险之间的关系，并探讨叶酸和 Hcy 是否可能在这种关联中起作用。
这项病例对照研究纳入了 129 名 MCI 患者、131 名 AD 患者和 134 名健康对照者。使用实时聚合酶链反应检测 LTL。使用化学发光酶免疫测定法检测血清叶酸水平，使用酶循环法测量血清 Hcy 水平。使用多元逻辑回归和多变量线性回归分析数据，同时调整潜在混杂因素。
对照组、MCI 组和 AD 组的平均 LTL 分别为 1.56±0.25、1.44±0.23 和 1.28±0.28（p<0.01）。在多元逻辑回归中，与最短 LTL 三分位组相比，最长 LTL 三分位组的 MCI（OR 0.246；95%CI 0.101-0.597）和 AD（OR 0.123；95%CI 0.044-0.345）的 OR 较低。较短的 LTL 与 MCI 和 AD 的 OR 呈剂量依赖性相关。此外，血清叶酸浓度与 LTL 呈正相关（p<0.01），而血清 Hcy 水平与 LTL 呈负相关（p<0.05）。在分层分析中，LTL-MCI/AD 相关性因血清叶酸和 Hcy 水平而异。
较短的 LTL 与 MCI/AD 的风险相关。叶酸和 Hcy 可能在这种关联中起重要作用。
