Homocysteine and folate as risk factors for dementia and Alzheimer disease

BACKGROUND: In cross-sectional studies, elevated plasma total homocysteine (tHcy) concentrations have been associated with cognitive impairment and dementia. Incidence studies of this issue are few and have produced conflicting results. OBJECTIVE: We investigated the relation between high plasma tHcy concentrations and risk of dementia and Alzheimer disease (AD) in an elderly population. DESIGN: A dementia-free cohort of 816 subjects (434 women and 382 men; mean age: 74 y) from an Italian population-based study constituted our study sample. The relation of baseline plasma tHcy to the risk of newly diagnosed dementia and AD on follow-up was examined. A proportional hazards regression model was used to adjust for age, sex, education, apolipoprotein E genotype, vascular risk factors, and serum concentrations of folate and vitamin B-12. RESULTS: Over an average follow-up of 4 y, dementia developed in 112 subjects, including 70 who received a diagnosis of AD. In the subjects with hyperhomocysteinemia (plasma tHcy > 15 micromol/L), the hazard ratio for dementia was 2.08 (95% CI: 1.31, 3.30; P = 0.002). The corresponding hazard ratio for AD was 2.11 (95% CI: 1.19, 3.76; P = 0.011). Independently of hyperhomocysteinemia and other confounders, low folate concentrations (< or = 11.8 nmol/L) were also associated with an increased risk of both dementia (1.87; 95% CI: 1.21, 2.89; P = 0.005) and AD (1.98; 95% CI: 1.15, 3.40; P = 0.014), whereas the association was not significant for vitamin B-12. CONCLUSIONS: Elevated plasma tHcy concentrations and low serum folate concentrations are independent predictors of the development of dementia and AD.     

Homocysteine and cognitive function in healthy elderly community dwellers in Italy

BACKGROUND: Elevated plasma total homocysteine (tHcy) concentrations are common in the elderly and have been suggested to be a risk factor for dementia. OBJECTIVE: In an elderly population, we examined the relation between plasma tHcy and scores on the Mini-Mental State Examination (MMSE), a commonly used screening measure of cognitive impairment in general practice. DESIGN: Fasting plasma tHcy concentrations were measured in 650 healthy, cognitively normal Italian community dwellers aged > or = 65 y (x +/- SD: 72.8 +/- 6.0 y). Socioeconomic status; serum folate, vitamin B-12, and creatinine; other potential dietary and lifestyle determinants of tHcy; and conventional vascular disease risk factors were also assessed. RESULTS: Subjects with MMSE scores of 26-28 had higher plasma tHcy concentrations (12.7 micromol/L; range: 12.2-13.2 micromol/L) than did those with scores > 28 (11.9 micromol/L; 11.4-12.3 micromol/L; P < 0.01). Subjects with scores of 24-25 had higher plasma tHcy concentrations (14.5 micro mol/L; 13.5-15.6 micromol/L) than did subjects with scores of 26-28 (P < 0.01) or > 28 (P < 0.001). The risk of hyperhomocysteinemia (plasma tHcy > 15 micromol/L) was higher in subjects with scores of 24-25 (odds ratio: 3.81; 95% CI: 1.9, 7.5) or 26-28 (odds ratio: 1.96; 95% CI: 1.3, 3.0) than in those with scores > 28. The results did not change after adjustment for conventional vascular risk factors and for age, medical, dietary, and lifestyle determinants of plasma tHcy. CONCLUSION: Elevated plasma tHcy has an independent, graded association with concurrent cognitive impairment as measured with the MMSE in healthy elderly community dwellers.     

Plasma tocopherols and risk of cognitive impairment in an elderly Italian cohort

BACKGROUND: Evidence that vitamin E may preserve cognitive function in elderly subjects is conflicting. The most abundant and most investigated form of vitamin E in humans is alpha-tocopherol, but other antioxidant tocopherols (beta, gamma, and delta) exist in nature. OBJECTIVE: We aimed to investigate plasma concentrations of the natural tocopherols and the tocopherol oxidation markers alpha-tocopherylquinone (alphaTQ) and 5-nitro-gamma-tocopherol (5NGT) in relation to cognitive function in the elderly. DESIGN: Baseline plasma tocopherols and their oxidation markers were measured in 761 elderly Italian subjects from a population-based cohort assessed in 1999-2000 for mild cognitive impairment (MCI) and dementia. In 2003-2004, information about cognitive status was collected for 615 of the 666 subjects without baseline cognitive impairment. Tocopherols and oxidation markers were analyzed as plasma absolute values divided by serum total cholesterol because lipids affect their blood availability. Analyses were adjusted for sociodemographic, genetic, lifestyle, and medical confounders. RESULTS: Compared with the corresponding lowest tertile, the risk of prevalent dementia was higher for the highest tertile of delta-tocopherol/cholesterol [odds ratio (OR): 3.87; 95% CI: 1.46, 10.27] and alphaTQ/cholesterol (4.02; 1.45, 11.14), but the risk of incident dementia was not directly associated with plasma vitamin E metabolites. A U-shaped association, with lower risk for intermediate tertiles, was found for prevalent MCI with 5NGT/cholesterol (0.39; 0.17, 0.91) and for incident dementia with gamma-tocopherol/cholesterol (hazard ratio: 0.42; 95% CI: 0.22, 0.84). CONCLUSIONS: Plasma concentrations of some non-alpha-tocopherol forms of vitamin E are associated with cognitive impairment in elderly people. However, the associations depend on concurrent cholesterol concentration and need further investigation.     

Homocysteine, folate, and vitamin B-12 in mild cognitive impairment, Alzheimer disease, and vascular dementia

BACKGROUND: Evidence supports an independent association between plasma total homocysteine concentrations and the risk of vascular disease. Recent epidemiologic studies reappraised the possibility that vascular risk factors might play a role in the pathogenesis not only of vascular dementia (VaD) but also of Alzheimer disease (AD). OBJECTIVE: The objective was to investigate the relations of mild cognitive impairment, AD, and VaD with blood homocysteine, folate, and vitamin B-12. DESIGN: The study population consisted of 314 consecutive subjects, 228 of whom were eligible for analyses. Plasma total homocysteine, serum folate, and serum vitamin B-12 concentrations were measured in 55 nondemented elderly control subjects, 81 mildly cognitively impaired subjects (Clinical Dementia Rating: 0.5), and 92 demented patients prevalently in a mild disease stage and with a clinical diagnosis of AD (n = 74) or VaD (n = 18). RESULTS: Subjects in the lowest folate tertile had significantly higher adjusted odds ratios (ORs) for mild cognitive impairment (OR: 3.1; 95% CI: 1.2, 8.1) and dementia (3.8; 1.3, 11.2). Hyperhomocysteinemia was significantly associated with dementia (adjusted OR: 4.3; 1.3, 14.7) and AD (adjusted OR: 3.7; 1.1, 13.1). In subjects with a Clinical Dementia Rating of 0.5, the mean (+/- SE) Mini-Mental State Examination score was significantly lower (P < 0.05) in the highest homocysteine tertile (24.5 +/- 0.5) than in the lowest tertile (26.6 +/- 0.5). No significant associations were found between minimum medial temporal lobe thickness or leukoaraiosis and any biochemical measure in the dementia and AD groups. CONCLUSIONS: These findings suggest that relative folate deficiency may precede AD and VaD onset. Hyperhomocysteinemia might also be an early risk factor for cognitive decline in the elderly, but its role in dementia development must be addressed in future longitudinal studies.     

Total homocysteine and cognitive decline in a community-based sample of elderly subjects: the Rotterdam Study.

Homocysteine has been associated with an increased risk of cardiovascular disease. Cardiovascular diseases have been related to cognitive decline. The authors investigated the association of homocysteine with concurrent cognitive impairment and subsequent cognitive decline in a random sample of 702 community-dwelling respondents aged 55 years or over to the prospective Rotterdam Study in 1990-1994. Multiple logistic regression was used to calculate odds ratios and 95 percent confidence intervals for the association between total homocysteine levels and cognitive impairment (Mini-Mental State Examination (MMSE) score <26) and cognitive decline (drop in MMSE score of >1 point/year). Mean duration of follow-up was 2.7 years. After adjustment for age, sex, and education, there was no relation between total homocysteine and cognitive impairment (highest vs. lowest tertile: odds ratio (OR) = 1.30, 95% confidence interval (CI): 0.50, 3.38) or cognitive decline (middle vs. lowest tertile: OR = 1.14, 95% CI: 0.67, 1.93; highest vs. lowest tertile: OR = 0.91, 95% CI: 0.52, 1.58). Subjects who were lost to follow-up due to death or nonresponse had slightly higher age-adjusted homocysteine levels and lower MMSE scores at baseline. Sensitivity analyses showed that selective loss to follow-up was not a likely explanation for the absence of an association in the participants. Although a relation between homocysteine and reduced cognitive function is biologically plausible, this study suggests no such association in a community-based sample of the elderly.     

Apolipoprotein E e4 allele affects risk of hyperhomocysteinemia in the elderly

BACKGROUND: Apolipoprotein E (APOE) plays a central role in VLDL metabolism. Both APOE e4 allele (APOE4) and C-reactive protein (CRP) are associated with greater risk of dementia and vascular disease, but APOE4 carriers have lower blood concentrations of CRP than do noncarriers, possibly through a mechanism favoring the clearance of the CRP VLDL-bound fraction. Homocysteine, another risk factor for vascular disease and dementia, also binds to VLDL in blood. However, the association between APOE4 and hyperhomocysteinemia has never been thoroughly investigated. OBJECTIVE: We investigated in an elderly population whether 1) APOE4 is associated with hyperhomocysteinemia [plasma total homocysteine (tHcy) > 15 micromol/L], 2) hyperhomocysteinemia affects the association between APOE4 and high CRP (serum CRP > 3 mg/L), and 3) B vitamin status affects these associations. DESIGN: APOE4 genotypes were assessed and tHcy, CRP, and serum concentrations of folate and vitamin B-12 were measured in 671 cognitively healthy subjects (52% women; mean age: 73 y) from an Italian population-based prospective cohort study. RESULTS: APOE4 carriers without high CRP [multivariate-adjusted odds ratio (OR): 0.22; 95% CI: 0.08, 0.59] had a lower risk of hyperhomocysteinemia than did noncarriers. The risk of high CRP was lower in APOE4 carriers without hyperhomocysteinemia (multivariate-adjusted OR: 0.51; 95% CI: 0.31, 0.85) than in noncarriers. The associations were not affected by B vitamin status. CONCLUSION: Independently from B vitamin status, APOE4 carriers have a lower risk of hyperhomocysteinemia and of high CRP than do noncarriers, but the presence of one condition attenuates the association of APOE4 with the other condition.     

Plasma vitamin B12, folate and homocysteine levels in gastrectomized men

BACKGROUND & AIMS: Hyperhomocysteinemia is a risk factor for cardiovascular disease, dementia and depression. Prevalence rate of hyperhomocysteinemia in gastrectomized patients is not well elucidated. METHODS: We compared plasma total homocysteine, vitamin B12 and folate of gastrectomized male patients with those of control subjects. RESULTS: Total homocysteine was higher in gastrectomized patients than in control subjects (11.7 +/- 4.4 micromol/l vs. 9.3 +/- 2.4 micromol/l, P = .011), while vitamin B12 was lower in patients than in control subjects (382 +/- 211 pg/ml vs. 500 +/- 179 pg/ml, P = .020). Folate of the two groups was comparable (5.8 +/- 2.5 ng/ml vs. 5.9 +/- 2.2 ng/ml). Of 31 gastrectomized patients six (19.4%) showed low vitamin B12 (<233 pg/ml), four (12.9%) low folate (<3.0 ng/ml) and seven (22.6%) hyperhomocysteinemia (>14 micromol/l), whereas they were found in one (3.2%), none (0%) and one (3.2%) of 31 control subjects, respectively. Patients who had undergone gastrectomy because of cancer showed higher total homocysteine compared to patients who had undergone it because of peptic ulcer. Type of surgery did not correlate with total homocysteine in the present study. CONCLUSION: Hyperhomocysteinemia is not rare in male Japanese gastrectomized patients.     

老年人认知功能障碍患病情况调查及影响因素分析

目的了解社区养老和机构养老老年人的认知功能障碍情况,探讨相关影响因素,为防治认知功能障碍提供科学依据。方法调查对象为545名广州市部分社区长者饭堂的用餐老年人和广州市、佛山市、中山市、清远市四地市养老院的入住老年人,对老年人的一般健康情况和认知功能(MoCA)进行问卷调查,对认知功能的影响因素进行Logistic回归分析。结果养老院老年人认知功能障碍的风险高于社区养老的老年人。养老院老年人(OR=3.099,95%CI:1.601,6.001)、年龄75岁以上(OR=2.050,95%CI:1.132,3.714)是老年人认知障碍的危险因素;学历与老年人的认知障碍呈负相关,高中或大学以上学历老年人认知功能障碍的风险低于文盲老年人(OR=0.292,95%CI:0.124,0.691)。结论应多关注社区养老和机构养老老年人的认知功能情况,及早发现认知功能障碍人群并进行干预,以减少认知功能障碍的进展性损害。     

上海市社区老年人轻度认知障碍的潜在危险因素

目的探寻社区老年人轻度认知功能障碍(MCI)的潜在危险因素,为MCI的一级预防提供依据。方法对上海市社区的老年人进行一项横断面研究。选择了368名年龄在65~80岁的受试者,完成简易智力状态检查量表(MMSE)、基本信息问卷调查和体格检查。采用Logistic回归分析MCI的潜在危险因素。结果所有参与调查的368名受试者中,共53例MCI患者,患病率为14.4%。单因素分析发现:高龄,受教育程度低,无叶酸补充,中风,骨质疏松症和高脂血症是MCI的危险因素。Logistic回归分析显示,高龄[OR=1.146(95%CI:1.052~1.249)]和骨质疏松症[OR=2.371(95%CI:1.042~5.396)]是MCI独立危险因素,高教育程度[OR=0.073(95%CI:0.011~0.478)]是保护因素。年龄可以影响MMSE评分各方面(所有P值<0.05)。定期补充叶酸的受试者MMSE评分更高,特别是语言能力得分(P=0.002)。骨质疏松症患者注意力和计算力得分较低(P=0.022)。结论MCI患病率随年龄增长而增加,教育程度低、骨质疏松症可能是老年人MCI的独立危险因素。叶酸补充剂虽与MCI间未观察到相关性,但可以改善其语言和实践表现。     

开封市社区老年人群轻度认知功能障碍患病率及危险因素研究

目的 调查开封市社区老年人轻度认知障碍(mild cognitive impairment,MCI)的患病率及潜在风险因素,为当地科学制定预防措施提供依据。方法 2018年5—11月,基于分层整群随机抽样方法选取开封市6个社区680名≥60岁老年人作为调查对象,使用中文版“简明精神状态量表”进行认知功能评估。结果 680名调查对象中,发现MCI患者153例,患病率22.50%。单因素分析显示,不同年龄、性别、文化教育程度和患有慢性病对MCI患病率差异有统计学意义(P＜0.05);多元logistic回归分析结果表明,控制混杂因素后,女性是老年人MCI的危险因素(OR=1.806,95%CI:1.088～2.998)。而年龄＜80岁(OR=0.736,95%CI:0.561～0.967)、小学文化程度(OR=0.680,95%CI:0.483～0.956)、初中文化程度(OR=0.396,95%CI:0.266～0.588)、高中及以上教育(OR=0.284,95%CI:0.115～0.700)是MCI的保护因素。结论 开封市老年人MCI患病率较高,女性、高龄、受教育程度低的老年人可能是MCI的高危人群,也是未来MCI防控的重点人群。     

High prevalence of hyperhomocysteinemia in Chinese adults is associated with low folate, vitamin B-12, and vitamin B-6 status

Elevated plasma total homocysteine (tHcy) concentrations are associated with lower folate, vitamin B-12, and vitamin B-6 status and are considered an independent risk factor for cardiovascular disease in developed countries, but data in developing countries are limited. We conducted a cross-sectional study to explore tHcy status and its association with plasma B vitamin status in 2471 Chinese men and women aged 35 to 64 y, living in the urban and rural areas of the northern and the southern regions of China. Blood samples were also collected in 2 seasons (spring and fall). The geometric mean plasma tHcy concentration was significantly higher in the north (adjusted geometric mean, 95% CI; 13.0 micromol/L, 12.6-13.3) than in the south (9.1, 8.9-9.4) after controlling for gender, area (urban and rural), age, and season (spring and fall). Twenty-eight percent of northerners and 7% of southerners had plasma tHcy concentrations>or=16.0 micromol/L, a level used to define hyperhomocysteinemia. Within each region, men had higher plasma tHcy concentrations than women (16.1 vs. 10.6 micromol/L in the north, and 10.7 vs. 7.9 micromol/L in the south) and 40% of the northern men had hyperhomocysteinemia. Generally, individuals living in the urban areas had 30% (95% CI, 1.0-1.6) greater odds of having high tHcy levels (>or=16 micromol/L) than those living in the rural areas. Low plasma concentrations of folate, vitamins B-12 and B-6, older age, being male, and living in urban areas were all independently associated with elevated tHcy, with low folate as the strongest determinant.     

Randomized controlled trial of homocysteine-lowering vitamin treatment in elderly patients with vascular disease

BACKGROUND: Homocysteine is an independent risk factor for vascular disease and is associated with dementia in older people. Potential mechanisms include altered endothelial and hemostatic function. OBJECTIVE: We aimed to determine the effects of folic acid plus vitamin B-12, riboflavin, and vitamin B-6 on homocysteine and cognitive function. DESIGN: This was a factorial 2 x 2 x 2, randomized, placebo-controlled, double-blind study with 3 active treatments: folic acid (2.5 mg) plus vitamin B-12 (500 microg), vitamin B-6 (25 mg), and riboflavin (25 mg). We studied 185 patients aged >or=65 y with ischemic vascular disease. Outcome measures included plasma homocysteine, fibrinogen, and von Willebrand factor at 3 mo and cognitive change (determined with the use of the Letter Digit Coding Test and on the basis of the Telephone Interview of Cognitive Status) after 1 y. RESULTS: The mean (+/-SD) baseline plasma homocysteine concentration was 16.5 +/- 6.4 micromol/L. This value was 5.0 (95% CI: 3.8, 6.2) micromol/L lower in patients given folic acid plus vitamin B-12 than in patients not given folic acid plus vitamin B-12 but did not change significantly with vitamin B-6 or riboflavin treatment. Homocysteine lowering with folic acid plus vitamin B-12 had no significant effect, relative to the 2 other treatments, on fibrinogen, von Willebrand factor, or cognitive performance as measured by the Letter Digit Coding Test (mean change: -1; 95% CI: -2.3, 1.4) and the Telephone Interview of Cognitive Status (-0.7; 95% CI: -1.7, 0.4). CONCLUSION: Oral folic acid plus vitamin B-12 decreased homocysteine concentrations in elderly patients with vascular disease but was not associated with statistically significant beneficial effects on cognitive function over the short or medium term.     

Homocysteine, B vitamins, and the incidence of dementia and cognitive impairment: results from the Sacramento Area Latino Study on Aging

BACKGROUND: High concentrations of homocysteine have been linked to a greater risk of Alzheimer disease, dementia, and cognitive decline. OBJECTIVE: We evaluated the association between homocysteine and 4.5-y combined incidences of dementia and cognitive impairment without dementia (CIND) in a cohort of 1779 Mexican Americans aged 60-101 y. DESIGN: Homocysteine, red blood cell (RBC) folate, and plasma vitamin B-12 were measured at baseline. New cases of dementia or CIND were ascertained by neuropsychological and clinical examinations and expert adjudication. We used proportional hazards models to estimate the risk of homocysteine-associated dementia or CIND and the influence of RBC folate and plasma vitamin B-12 on that association. RESULTS: High homocysteine concentrations were associated with a greater risk of dementia or CIND: hazard ratio (HR): 2.39; 95% CI: 1.11, 5.16. Plasma vitamin B-12 modified the association between homocysteine and the outcome. The rates of dementia or CIND associated with homocysteine for those in the lowest and highest tertiles of vitamin B-12, respectively, were significantly higher (HR: 1.61, P = 0.04) and lower (HR: 0.94, P = 0.015) than the risk for those in the middle tertile. CONCLUSIONS: Homocysteine is an independent risk factor for both dementia and CIND. Higher plasma vitamin B-12 may reduce the risk of homocysteine-associated dementia or CIND.     

血浆同型半胱氨酸水平和生活饮食习惯与胃癌发病风险的关联研究

目的探讨江苏省扬中和宜兴市胃癌高发区人群血浆总同型半胱氨酸(tHcy)水平、生活饮食习惯与胃癌易感性的关系。方法采用以人群为基础的病例对照研究。经组织学确诊的高发区胃腺癌病例391例,并选择与病例年龄和性别频数匹配的人群对照608例,通过酶转换法定量检测血浆tHcy的浓度,比较不同tHcy水平与胃癌风险的关系,并探讨摄入蔬菜、水果、吸烟、饮酒等因素在其中的影响。结果胃癌患者血浆tHcy平均水平显著高于对照组(P=0．002)。同时按照正常对照组人群的血浆tHcy四分位数(7．9、10．1、13.7μmol／L)分类,以血浆tHcy≤7．9μmol／L为参照组,随着tHcy的增加,罹患胃癌的风险分别增加67％(调整OR=1．67,95％CI:1．12～2．48)、98％(调整OR=1．98,95％CI:1．33～2．94)和112％(调整OR=2．12,95％CI:1．44～3．15),并且呈现显著的递增趋势(x2=15．78,P<0．001)。同时摄入蔬菜、水果相对较多时可降低胃癌的发病风险。叉生分析表明,较少摄入蔬菜、水果、吸烟和饮酒者同时血浆tHcy>15．0μmol／L时罹患胃癌的风险比两种因素单独作用时的风险增强,但交互作用不显著。结论血浆高水平tHcy可增加罹患胃癌的风险,同时较少摄入蔬菜、水果、吸烟和饮酒等不良饮食生活习惯均可增加患病风险。     

Homocysteine and its determinants in nondialyzed chronic kidney disease patients

This cross-sectional study aimed to investigate the prevalence of hyperhomocysteinemia, the determinants of plasma total homocysteine concentrations, and the relationship of total homocysteine with nutritional parameters in a sample of patients with chronic kidney disease (CKD) and not yet on dialysis. The study was done with outpatients from the Nephrology Division of the Federal University of S?o Paulo and Oswaldo Ramos Foundation. Sixty-six patients with CKD (70% male; age 58.6+/-15.6 years [mean+/-standard deviation]) with moderate to severe renal impairment (creatinine clearance=29.8+/-14.3 mL/min [0.5+/-0.24 mL/sec]), clinically stable, and older than 18 years were included. A group of 20 healthy subjects from the clinic staff was also studied for reference values for plasma homocysteine, folate, and vitamin B-12 concentration. Fasting blood samples were collected to determine plasma total homocysteine, folate, vitamin B-12, and creatinine. To calculate creatinine clearance, a 24-hour urine collection sample was obtained. The assessment of nutritional status included anthropometric parameters. Pearson correlation, Mann-Whitney test, and multiple linear regression analysis were used for statistical analyses. The main results showed that the concentration of total homocysteine in the patients was significantly increased compared with the healthy subjects (3.4+/-1.7 vs 1.41+/-0.42 mg/L [25.4+/-12.2 vs 10.4+/-3.1 micromol/L]; P<0.001). Plasma folate and plasma vitamin B-12 were in the normal range and did not differ between patients and healthy individuals. A high prevalence of hyperhomocysteinemia (total homocysteine >1.89 mg/L [14 micromol/L]) was found in the patients (89%). Plasma total homocysteine did not correlate with any of the nutritional parameters studied and did not differ between patients in terms of whether they were using or not using folic acid supplementation (3.07+/-1.09 vs 3.55+/-1.78 mg/L [22.7+/-8.1 vs 26.3+/-13.2 micromol/L]; P=0.47), although plasma folate was significantly higher in the supplemented group (12.6+/-3.0 vs 8.0+/-3.6 ng/mL [28.5+/-6.8 nmol/L vs 18.1+/-8.2 nmol/L]; P<0.001). According to the multiple regression analysis, the determinants of total homocysteine were only plasma folate, plasma vitamin B-12, and creatinine clearance (r2=0.20). In conclusion, a high prevalence of hyperhomocysteinemia was found in our sample of nondialyzed patients with CKD. The determinants of total homocysteine levels were plasma folate, plasma vitamin B-12, and creatinine clearance. No association between nutritional parameters and total homocysteine was observed.     

Plasma total homocysteine is influenced by prandial status in humans: the Hordaland Hhomocysteine Sstudy

Plasma total homocysteine (tHcy) is a risk factor for cardiovascular disease, adverse pregnancy outcomes and impaired cognitive function. No population-based studies on the possible influence of prandial status on tHcy have been published. The aim of this study was to investigate the variation in plasma tHcy levels in relation to time since last meal. A cross-sectional, population-based study including 18,044 individuals in Western Norway was conducted. Most subjects were in the age groups 40-42 and 65-67 y. Participants who had not eaten during the past 6 h before the blood sampling had significantly higher mean tHcy levels compared with those who had eaten; 11.7 [95% confidence interval (CI): 11.4-12.1] vs. 11.2 (95% CI: 11.1-11.3) micromol/L among men (P = 0.03) and 10.2 (95% CI: 9.9-10.6) vs. 9.7 (95% CI: 9.6-9.7) micromol/L among women (P = 0.003). In all groups except older women, tHcy concentrations were generally higher with increasing time after a meal (P-trend <0.01 in all 3 groups). These findings suggest that fasting status and time since last meal may influence levels of tHcy and should be considered in studies of tHcy as a risk factor for cardiovascular and other diseases, and when comparing tHcy values among studies.     

孤独感对社区老年人轻度认知障碍的影响

目的 了解重庆市社区老年人孤独感与轻度认知障碍（mild cognitive impairment, MCI）的现状,探讨孤独感对老年人MCI的影响。方法 采用多阶段随机抽样方法,选取重庆市9个社区的1375例老年人作为研究对象,采用UCLA孤独量表和蒙特利尔认知评估量表（MoCA）调查社区老年人的孤独感和MCI状况。结果 社区老年人孤独感得分为36.36±7.67分,中等及以上水平孤独感者占43.78％。老年人MoCA总分为24.65±3.78分,MCI的检出率为28.44％。不同水平孤独感老年人的MoCA总分及其各维度得分均具有统计学差异（P＜0.05）。Logistic回归分析显示,中等水平孤独感（OR=1.476,95％CI:1.047～2.079）和高水平孤独感（OR=1.731,95％CI:1.026～2.921）是社区老年人MCI的危险因素。结论 社区老年人孤独感和MCI的检出率较高,且孤独感水平越高,MCI的检出率越高。社区工作人员应采取措施减轻老年人的孤独状况,从而延缓其认知功能的下降,改善老年人的生活质量。     

A proinflammatory state is associated with hyperhomocysteinemia in the elderly

BACKGROUND: The mechanism by which high circulating homocysteine concentrations are a risk factor for atherothrombosis is incompletely understood. A proinflammatory state is related to atherosclerosis, and recent studies suggest that acute phase reactants correlate with circulating concentrations of homocysteine. OBJECTIVE: We determined whether high concentrations of inflammatory markers are associated with hyperhomocysteinemia independently of dietary vitamin intakes, vitamin concentrations, and cardiovascular disease risk factors in a large, representative sample of the general population. DESIGN: Five hundred eighty-six men and 734 women were randomly selected from the inhabitants of 2 small towns near Florence, Italy. RESULTS: After adjustment for multiple potential confounders, interleukin 1 receptor antagonist (IL-1ra) and interleukin 6 (IL-6) concentrations were significantly (P < 0.001) associated with plasma homocysteine concentrations in older (>65 y) populations. Compared with participants in the lowest IL-6 tertile, those in the highest tertile had a higher risk of having homocysteine concentrations that were high (>30 micromol/L; odds ratio: 2.6; 95% CI: 1.1, 5.6; P = 0.024) or in the intermediate range 15-30 micromol/L (odds ratio: 1.6; 95% CI: 1.2, 2.2; P = 0.0014). Sedentary state, intakes of vitamin B-6 and folic acid, and serum folate, vitamin B-12, vitamin B-6, and alpha-tocopherol concentrations were significant independent correlates of homocysteine. CONCLUSIONS: High circulating concentrations of IL-1ra and IL-6 are independent correlates of hyperhomocysteinemia and may explain, at least in part, the association between homocysteine and atherosclerosis.     

外周血白细胞端粒长度与轻度认知障碍老年人发生风险关联的病例对照研究

目的探讨轻度认知障碍(mild cognitive impairment,MCI)老年人外周血白细胞端粒长度(leukocyte telomere length,LTL)与MCI发生风险之间的关联。方法于2017年10月―2017年12月在天津市南开区王顶堤街道的5个社区纳入MCI和健康对照老年受试者进行病例对照设计,实施问卷调查和静脉血样采集,用实时荧光定量多聚核苷酸链式反应(real-time quantitative polymerase chain reaction,qPCR)进行LTL的测量。采用多元Logistic回归分析模型分析LTL不同水平与MCI发生风险之间的关联。结果两组受试对象都为183例。MCI组LTL水平(1.44±0.23)低于对照组(1.66±0.23),两组差异具有统计学意义(Z=-8.94,P<0.001)。调整年龄、性别、教育程度、吸烟、饮酒、糖尿病、高血压、心脏病后,较低水平LTL与MCI发生风险存在统计学意义关联(均有P<0.05);与LTL第一水平组相比,其二、三、四水平组MCI发生风险的比值比(odds ratio,OR)及95%置信区间(95%confidence interval,95%CI)分别为0.262(0.130~0.531)、0.088(0.043~0.180)、0.083(0.040~0.169)。结论外周血白细胞短端粒可能是MCI发生的独立危险因素,并且随着LTL缩短,MCI发生风险增加。     

社区老年人久坐行为与睡眠质量对认知功能的影响

目的 了解久坐行为与睡眠质量对社区老年人认知功能的影响。方法 采用匹兹堡睡眠质量指数量表、国际体力活动问卷短卷、简易精神状态量表及一般资料调查表,于2019年12月按照分层整群抽样法,从济南市随机抽取1 091名老年人开展问卷调查。结果 调整人口学变量后,二元logistic 回归分析结果显示,存在久坐行为的社区老年人患认知功能障碍的风险为非久坐行为者的1.880倍（OR值 = 1.880, 95 % CI = 1.267～2.790）,存在睡眠障碍的老年人发生认知功能障碍的风险为无睡眠障碍者的2.160倍（OR值 = 2.160,95 % CI = 1.391～3.356）。交互作用分析结果显示,久坐行为与睡眠障碍对老年人认知功能障碍患病率具有负相乘交互作用OR值（95%CI） = 0.414（0.174～0.984）。结论 久坐行为与睡眠障碍是老年人认知功能的危险因素,且二者存在相乘交互作用。