Homocysteine (Hcy) is a risk factor for brain atrophy, cognitive impairment, and dementia. Vitamin B₁₂ and folate are cofactors necessary for the methylation of Hcy. However, there is some debate regarding the differing levels of plasma Hcy and serum folate and vitamin B₁₂ among healthy controls, patients with mild cognitive impairment (MCI), and patients with Alzheimer’s disease (AD). This study aimed to evaluate how the levels of plasma Hcy and its biological determinants, folate and vitamin B₁₂, are related to MCI and AD in older Chinese adults. This is a case-control study including 112 subjects with MCI, 89 AD patients and 115 healthy controls. Diagnosis of AD was made according to the NINCDS-ADRDA and MCI with modified Petersen’s criteria. Serum folate and vitamin B₁₂ concentrations were analyzed by radioimmunoassay, and plasma Hcy was assessed by a high-performance liquid chromatography-fluorescence method. Multivariate analysis of regression was used to examine the odds ratio (OR) of MCI or AD with Hcy or vitamin levels. Results have shown that serum folate and vitamin B₁₂ levels were significantly lower, but the plasma Hcy level was higher, in patients with MCI and AD than in healthy controls. Multivariate regression analyses showed that subjects in the lowest folate tertile had significantly higher adjusted ORs for MCI (OR: 3.07; 95% confidence interval [CI]: 1.12, 8.07) and AD (3.42; 95% CI: 1.15, 8.34) compared to subjects in the highest tertile. The highest Hcy tertile was significantly associated with MCI (adjusted OR: 2.81; 95% CI: 1.15, 4.73) and AD (adjusted OR: 3.64; 95% CI: 1.13, 9.04) compared to the lowest tertile. No association existed between low vitamin B₁₂ levels and AD or MCI (p > 0.05). Low blood levels of folate and vitamin B₁₂ and elevated Hcy levels were associated with MCI and AD in older Chinese adults, and the association was stronger for AD.

High lipid levels may constitute a more important risk factor for cognitive health in previous studies. However, the association of plasma lipids with mild cognitive impairment (MCI) among elderly people had not been studied exactly. This study aims to explore the relationship between plasma lipids/lipoproteins and the risk of MCI in elderly Chinese individuals. CSI-MCI study was a preliminary case-control study of the association of plasma lipids/lipoproteins with MCI in 112 MCI cases and 115 cognitively normal controls. Plasma total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) levels were measured in fasting blood samples. Multivariable logistic regression was used to evaluate the potential association between MCI and these factors. Statistical models were adjusted for multiple demographic and biological covariates. The subjects with MCI were significantly older, higher percentage of females and less educated than controls (P <0.05). As expected, subjects with MCI had lower MMSE score compared with controls (P <0.05). Multivariate logistic regression analysis showed that higher plasma TC level was associated with the risk of MCI in models adjusting for age, sex and education. However, This association was attenuated after adjusting for BMI, Type 2 diabetes mellitus, heart disease and hypertension. Plasma TG level was negatively associated with the risk of MCI. The adjusted odds ratio (OR) of MCI was significantly reduced for the highest quartile of plasma TG level (OR: 0.76, 95 % CI: 0.48–0.97), but not for the second or third quartile, compared with the lowest quartile (adjusted models). Plasma HDL level was significantly negatively associated with the risk of MCI. There was no association between plasma LDL level and the risk of MCI, adjustment for demographics, vascular disorders did not change this relation. Plasma TC was significantly higher in MCI subjects compared to cognitively normal controls, Elevated plasma HDL and triglyceride were associated with the occurrence of MCI. These findings need to be confirmed in further longitudinal studies.

Docosahexaenoic acid (DHA) is important for brain function, and higher DHA intake is inversely correlated with relative risk of Alzheimer’s disease. The potential benefits of DHA supplementation in people with mild cognitive impairment (MCI) have not

Geriatric depression, a chronic condition, has become a substantial burden in rural China. This study aimed to assess the association between dietary patterns and the risk of geriatric depression in rural China. Between March 2018 and June 2019, 3304 participants were recruited for this cross-sectional study in rural Tianjin, China. Principal component analysis was used to determine the major dietary patterns. The associations between dietary patterns and the risk of geriatric depression were assessed using a logistic regression model. Four dietary patterns were identified: vegetables-fruit, animal food, processed food, and milk-egg. The study found that vegetable-fruit (Q2 vs. Q1: OR = 0.62, 95% CI: 0.46–0.83; Q3 vs. Q1: OR = 0.54, 95% CI: 0.38–0.75; Q4 vs. Q1: OR = 0.39, 95% CI: 0.26–0.57) and animal food patterns (Q3 vs. Q1: OR = 0.69, 95% CI: 0.50–0.95; Q4 vs. Q1: OR = 0.58, 95% CI: 0.41–0.82) were associated with a decreased risk of depression, and inflammatory dietary pattern (Q2 vs. Q1: OR = 1.71, 95% CI: 1.23–2.38; Q3 vs. Q1: OR = 1.70, 95% CI: 1.22–2.36; Q4 vs. Q1: OR = 1.44, 95% CI: 1.03–2.03) was associated with an increased risk of depression. The present findings reinforce the importance of adopting an adequate diet consisting of vegetables, fruit and animal foods, while limiting the intake of pro-inflammatory foods, to decrease the risk of depression.

Background: Mild cognitive impairment (MCI) represents an intermediate and modifiable stage between normal aging and dementia. There is an urgent need for simple, non-invasive testing of MCI by blood biomarkers. Objective: This study aimed to retrospectively evaluate the association of red blood cell (RBC) indices with MCI, and select the best hematologic characteristic for detection of MCI in elderly Chinese. Methods: Matched case-control study was carried out with 85 pairs of MCI subjects and healthy controls. The matching criteria was age, gender and education attainment. All samples were analyzed for RBC indices, including hemoglobin (HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width-standard deviation (RDW-SD). A conditional logistic regression model was used to evaluate the association between RBC indices and MCI. The diagnostic efficacy of the biomarkers was evaluated by receiver operating characteristics (ROC). Results: Among all RBC indices, there were significant differences in HGB (124.82 +/- 7.89 vs. 133.93 +/- 4.52, P < 0.001) and RDW-SD (45.29 +/- 2.03 vs. 41.34 +/- 4.41, P < 0.001) between two groups. In the logistic regression model, after adjustment for lifestyle factors and comorbidities, significant statistically associations have been found between higher HGB and lower risk of MCI (adjusted OR: 0.831; 95% CI: 0.773-0.893), higher RDW-SD and a higher risk of MCI (adjusted OR: 1.575; 95% CI: 1.326-1.872). ROC analysis suggested that the largest area under the ROC curve (AUC) was found with the combination of HGB and RDW-SD (AUC = 0.842), followed by HGB(AUC = 0.795), and finally by modest RDW-SD (AUC = 0.777). Combination of HGB 43.4 fL yielded a sensitivity of 92% and a specificity of 89%, overall diagnosis efficiency of which were better than HBG and RDW-SD alone. Conclusion: Lower HGB and higher RDW-SD alone were significantly found to be associated with increased risk of MCI, and offered modest sensitivity and specificity as a diagnostic marker. The combination of HGB and RDW-SD was more sensitive and had higher classification accuracy for differentiating MCI from healthy controls. Further prospective research is needed to clarify whether HGB in combination with RDW-SD may be a potential diagnostic tool for early diagnosis of AD.