Vitamin B-12 malabsorption and renal function are critical considerations in studies of folate and vitamin B-12 interactions in cognitive performance: NHANES 2011-2014

Anti-Inflammatory Diet and Protein-Enriched Diet Can Reduce the Risk of Cognitive Impairment among Older Adults: A Nationwide Cross-Sectional Research

BACKGROUND

Cognitive impairment (CI) is a common mental health disorder among older adults, and dietary patterns have an impact on cognitive function. However, no systematic researches have constructed anti-inflammatory diet (AID) and protein-enriched diet (PED) to explore their association with CI among older adults in China.

METHODS

The data used in this study were obtained from the 2018 waves of the China Longitudinal Health and Longevity Survey (CLHLS). We construct AID, PED, and calculate scores for CI. We use binary logistic regression to explore the relationship between them, and use restrictive cubic splines to determine whether the relationships are non-linear. Subgroup analysis and sensitivity analysis were used to demonstrate the robustness of the results.

RESULTS

A total of 8692 participants (mean age is 83.53 years) were included in the analysis. We found that participants with a higher AID (OR = 0.789, 95% confidence interval: 0.740-0.842, p < 0.001) and PED (OR = 0.910, 95% confidence interval: 0.866-0.956, p < 0.001) score showed lower odds of suffering from CI. Besides, the relationship between the two dietary patterns and CI is linear, and the results of subgroup analysis and sensitivity analysis are also significant.

CONCLUSION

Higher intakes of AID and PED are associated with a lower risk of CI among older adults, which has important implications for future prevention and control of CI from a dietary and nutritional perspective.

Association between the circulating very long-chain saturated fatty acid and cognitive function in older adults: findings from the NHANES

BACKGROUND

Age-related cognitive decline has a significant impact on the health and longevity of older adults. Circulating very long-chain saturated fatty acids (VLSFAs) may actively contribute to the improvement of cognitive function. The objective of this study was to investigate the associations between arachidic acid (20:0), docosanoic acid (22:0), tricosanoic acid (23:0), and lignoceric acid (24:0) with cognitive function in older adults.

METHODS

This study used a dataset derived from the 2011-2014 National Health and Nutrition Examination Survey (NHANES). A total of 806 adults (≥ 60 years) were included who underwent comprehensive cognitive testing and plasma fatty acid measurements. Multivariable linear regression, restricted cubic spline (RCS), and interaction analyses were used to assess associations between VLSFAs and cognitive function. Partial Spearman' s correlation analysis was used to examine the correlations between VLSFAs and palmitic acid (16:0), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, total cholesterol, triglycerides, systemic inflammatory markers, and dietary nutrients.

RESULTS

Multivariable linear regression analysis, adjusting for sociodemographic, clinical conditions, and lifestyle factors, showed that 22:0 and 24:0 levels were positively associated with better global cognitive function (β = 0.37, 95% confidence interval [CI] = 0.01, 0.73; β = 0.73, 95% CI = 0.29, 1.2, respectively) as well as better CEARD-DR Z-score (β = 0.82, 95% CI = 0.36, 1.3 and β = 1.2, 95% CI = 0.63, 1.8, respectively). RCS analysis showed linear associations between higher 22:0 and 24:0 levels and better cognitive performance in both global cognitive function and CERAD-DR tests.

CONCLUSIONS

The study suggests that higher levels of 22:0 and 24:0 are associated with better global cognitive function in older adults. 22:0 and 24:0 may be important biomarkers for recognizing cognitive impairment, and supplementation with specific VLSFAs (22:0 and 24:0) may be an important intervention to improve cognitive function. Further studies are needed to elucidate the underlying biological mechanisms between VLSFAs and cognitive function.

Development and validation of a cognitive dysfunction risk prediction model for the abdominal obesity population

Objectives

This study was aimed to develop a nomogram that can accurately predict the likelihood of cognitive dysfunction in individuals with abdominal obesity by utilizing various predictor factors.

Methods

A total of 1490 cases of abdominal obesity were randomly selected from the National Health and Nutrition Examination Survey (NHANES) database for the years 2011-2014. The diagnostic criteria for abdominal obesity were as follows: waist size ≥ 102 cm for men and waist size ≥ 88 cm for women, and cognitive function was assessed by Consortium to Establish a Registry for Alzheimer's Disease (CERAD), Word Learning subtest, Delayed Word Recall Test, Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST). The cases were divided into two sets: a training set consisting of 1043 cases (70%) and a validation set consisting of 447 cases (30%). To create the model nomogram, multifactor logistic regression models were constructed based on the selected predictors identified through LASSO regression analysis. The model's performance was assessed using several metrics, including the consistency index (C-index), the area under the receiver operating characteristic (ROC) curve (AUC), calibration curves, and decision curve analysis (DCA) to assess the clinical benefit of the model.

Results

The multivariate logistic regression analysis revealed that age, sex, education level, 24-hour total fat intake, red blood cell folate concentration, depression, and moderate work activity were significant predictors of cognitive dysfunction in individuals with abdominal obesity (p < 0.05). These predictors were incorporated into the nomogram. The C-indices for the training and validation sets were 0.814 (95% CI: 0.875-0.842) and 0.805 (95% CI: 0.758-0.851), respectively. The corresponding AUC values were 0.814 (95% CI: 0.875-0.842) and 0.795 (95% CI: 0.753-0.847). The calibration curves demonstrated a satisfactory level of agreement between the nomogram model and the observed data. The DCA indicated that early intervention for at-risk populations would provide a net benefit, as indicated by the line graph.

Conclusion

Age, sex, education level, 24-hour total fat intake, red blood cell folate concentration, depression, and moderate work activity were identified as predictive factors for cognitive dysfunction in individuals with abdominal obesity. In conclusion, the nomogram model developed in this study can effectively predict the clinical risk of cognitive dysfunction in individuals with abdominal obesity.

Association between dietary vitamin B1 intake and cognitive function among older adults: a cross-sectional study

BACKGROUND

This study aims to investigate the relationship between vitamin B1 intake and cognitive function in older adults.

METHODS

This cross-sectional observational study utilized data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. A total of 2422 participants were included in the analysis, with dietary vitamin B1 intake being determined by averaging two 24-h dietary recalls. Cognitive function was assessed using three cognitive function tests: the Digit Symbol Substitution Test (DSST) for processing speed, the Animal Fluency Test (AFT) for executive function, a Consortium to Establish a Registry for Alzheimer's disease (CERAD) subtest for memory. Test-specific and global cognition z score was created. Multivariate linear regression models were used to explore the association between vitamin B1 and cognitive function.

RESULTS

2422 participants, aged 60 years and older, were included from NHANES across two survey cycles (2011-2014). Higher vitamin B1 intake was associated with higher DSST, AFT scores (P < 0.001) as well as the global cognition z score (P = 0.008). In the fully adjusted model, as compared to the lowest quartile (Q1), the highest quartile (Q4) of vitamin B1 intake was related to higher DSST score (β = 2.23, 95% CI 0.79 ~ 3.67) and global cognition z sore (β = 0.09, 95% CI 0.02 ~ 0.16). The association between dietary vitamin B1 intake and cognitive function scores in US adults is linear. There was no detected significant statistical interaction between these variables.

CONCLUSIONS

Increased dietary intake of vitamin B1 was associated with better cognitive function in individuals aged over 60.

Increased serum methylmalonic acid levels were associated with the presence of cognitive dysfunction in older chronic kidney disease patients with albuminuria

BACKGROUND

This study aimed to evaluate the correlation between serum methylmalonic acid (MMA) levels and cognition function in patients with chronic kidney disease (CKD).

METHODS

In this cross-sectional study, we included 537 CKD individuals aged ≥ 60-year-old with albuminuria from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Four cognitive tests including the Digit Symbol Substitution Test (DSST), the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Delayed Recall and Word Learning tests, and the Animal Fluency test (AF) were performed. Associations between MMA and cognition scores were assessed with linear regression models.

RESULTS

MMA level was negatively associated with residual renal function and nutrition status. After multivariate adjustment, elevated serum MMA levels were independently correlated with decline of cognition in CKD patients with albuminuria.

CONCLUSION

Our study showed that higher serum MMA levels were independently associated with the presence of cognition dysfunction in CKD patients. The exact pathogenesis of MMA and cognition needs further research.

Sex Differences in the Association Between LDL/HDL with Cognitive Decline in Older Adults: National Health and Nutrition Examination Survey

Background

Lipids have a significant impact on the development and functioning of the nervous system, but the sex differences between the association of LDL/HDL, which reflects lipid metabolic status, and cognitive impairment remains unclear.

Objective

We aimed to determine if there were sex differences between the association of LDL/HDL and cognitive function in US older adults.

Methods

This population-based cross-sectional study used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2012 and 2013-2014 cycles. The main outcome was poor cognitive performance defined by the Digit Symbol Substitution Test (DSST) <  34 based on published literature.

Results

A total of 1,225 participants were included in the study, with a cognitive impairment incidence of 25.6% (314/1,225). Multivariate regression models demonstrated a significant association between cognitive decline and each 1-unit increase in LDL/HDL, after adjusting for all covariates (adjusted odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.11-1.67). Furthermore, subgroup analysis revealed an interaction between LDL/HDL and cognitive impairment in sex subgroups.

Conclusions

LDL/HDL was associated with cognitive impairment in the US older adult population in adjusted models, although the significance of this association was not observed in females.

Low vitamin B12 levels may predict the risk of ischemic stroke: A cross-sectional study

BACKGROUND

To examine serum vitamin B12 concentrations in relation to the risk of ischemic stroke among hospitalized patients in the Department of Neurology.

METHODS

We performed a cross-sectional study involving 2,212 inpatients discharged from the Department of Neurology of the First Affiliated Hospital of Chongqing Medical University, from January 2020 to January 2022. The results of laboratory assays such as serum vitamin B12, homocysteine, and folate levels were measured. Logistic regression analysis was used to investigate the association between serum vitamin B12 concentrations and ischemic stroke, with adjustment for a number of relevant demographic and lifestyle factors and comorbidities.

RESULTS

A total of 961 (43.4%) patients had an ischemic stroke. In the fully adjusted model, logistic regression analysis suggested a positive association between serum vitamin B12 levels<150 pg/mL (aOR: 1.42; 95% CI 1.02-1.97; p = 0.035), serum vitamin B12 150-300 pg/mL (aOR: 1.37; 95% CI 1.11-1.68; p = 0.003) and the prevalence of ischemic stroke. Furthermore, an inverse association was observed between serum vitamin B12 levels ≥ 900 pg/mL (aOR: 0.38; 95% CI: 0.19-0.77; p =0.007) and the prevalence of ischemic stroke. Moreover, the cut-off value of vitamin B12 concentration was 316.4 pg/mL and the discrimination power of the score evaluated by AUC-ROC was 0.71 (95%CI 0.68-0.73, p<0.001) in the vitamin B12 and ischemic stroke.

CONCLUSION

Findings suggest that low vitamin B12 levels may predict the risk of ischemic stroke, early and timely supplementation of vitamin B12 can improve the short-term prognosis of ischemic stroke patients.

Folate and vitamin B12 usual intake and biomarker status by intake source in United States adults aged ≥19 y: NHANES 2007-2018

BACKGROUND

Folate and vitamin B12 are important biomarkers of nutritional status of populations.

OBJECTIVES

This study aims to estimate folate and vitamin B12 usual intakes among United States adults and examine folate and vitamin B12 biomarker status by intake source.

METHODS

We analyzed data for United States adults aged ≥19 y from National Health and Nutrition Examination Survey 2007-2018 (n = 31,128), during which time voluntary corn masa flour (CMF) fortification was started. Usual intake was estimated using the National Cancer Institute method. Folate intake included folate from natural foods and folic acid from 4 sources: enriched cereal grain products (ECGPs), CMF, ready-to-eat cereals (RTEs), and folic acid-containing supplements (SUP). Vitamin B12 intake was mainly from food and supplements.

RESULTS

The median natural food folate intake (222 μg dietary folate equivalents (DFE)/d) was below the estimated average requirement (EAR) of 320 μg DFE/d. The proportions of those who consumed folic acid from ECGP/CMF only, ECGP/CMF + RTE, ECGP/CMF + SUP, and ECGP/CMF + RTE + SUP were 50%, 18%, 22%, and 10%, respectively. Median usual folic acid intakes (μg/d) were 236 (IQR: 152, 439) overall and 134, 313, 496, and 695 in the ECGP/CMF only, ECGP/CMF + RTE, ECGP/CMF + SUP, and ECGP/CMF + RTE + SUP folic acid consumption groups, respectively. Overall, 2.0% (95% CI: 1.7%, 2.3%) of adults, all of whom used folic acid supplements, consumed greater than the tolerable upper intake level (UL) of 1000 μg/d folic acid. The median usual vitamin B12 intake (μg/d) was 5.2 for vitamin B12 supplement nonusers and 21.8 for users. Consumption of RTE and/or supplements with folic acid was associated with higher serum and red blood cell folate concentrations. Vitamin B12 supplement users had significantly higher serum vitamin B12 concentrations.

CONCLUSIONS

Folic acid fortification plays a critical role in helping United States adults meet the folate EAR. At current fortification levels, United States adults who do not consume supplements do not have the usual folic acid intake exceeding the UL.

Folic Acid and the Prevention of Birth Defects: 30 Years of Opportunity and Controversies

For three decades, the US Public Health Service has recommended that all persons capable of becoming pregnant consume 400 μg/day of folic acid (FA) to prevent neural tube defects (NTDs). The neural tube forms by 28 days after conception. Fortification can be an effective NTD prevention strategy in populations with limited access to folic acid foods and/or supplements. This review describes the status of mandatory FA fortification among countries that fortify (n = 71) and the research describing the impact of those programs on NTD rates (up to 78% reduction), blood folate concentrations [red blood cell folate concentrations increased ∼1.47-fold (95% CI, 1.27, 1.70) following fortification], and other health outcomes. Across settings, high-quality studies such as those with randomized exposures (e.g., randomized controlled trials, Mendelian randomization studies) are needed to elucidate interactions of FA with vitamin B12 as well as expanded biomarker testing.

Non-Linear Association between Folate/Vitamin B12 Status and Cognitive Function in Older Adults

Although folate and vitamin B12 status have long been implicated in cognitive function, there is no consensus on the threshold of folate and vitamin B12 for assessing their impacts on cognition. The goal of this study was to detail the association between folate and vitamin B12 with cognitive performance. We analyzed cross-sectional data of older adults (≥60 y; n = 2204) from the NHANES (National Health and Nutrition Examination Surveys) cohort from 2011–2014. The restricted cubic spline model was used for describing the associations between serum total folate, RBC folate, 5-methyltetrahydrofolate, and vitamin B12 and the Consortium to Establish a Registry for Alzheimer’s Disease Word Learning (CERAD-WL) and Delayed Recall (CERAD-DR) tests, the Animal Fluency (AF) test, and the Digit Symbol Substitution Test (DSST), respectively. Older adults with a different folate and vitamin B12 status were clustered by artificial intelligence unsupervised learning. The statistically significant non-linear relationships between the markers of folate or vitamin B12 status and cognitive function were found after adjustments for potential confounders. Inverse U-shaped associations between folate/vitamin B12 status and cognitive function were observed, and the estimated breakpoint was described. No statistically significant interaction between vitamin B12 and folate status on cognitive function was observed in the current models. In addition, based on the biochemical examination of these four markers, older adults could be assigned into three clusters representing relatively low, medium, and high folate/vitamin B12 status with significantly different scores on the CERAD-DR and DSST. Low or high folate and vitamin B12 status affected selective domains of cognition, and was associated with suboptimal cognitive test outcomes.

Causal effects of homocysteine levels on the components of sarcopenia: A two-sample mendelian randomization study

Background: Currently, it is unclear whether there is a causal association between genetically predicted plasma homocysteine (Hcy) levels and the risk of sarcopenia. We performed a Mendelian randomization (MR) study to assess the association between circulating Hcy levels and the components [grip strength, walking pace, and appendicular lean mass (ALM)] of sarcopenia. Methods: Independent single nucleotide polymorphisms (SNPs) significantly associated with plasma Hcy levels served as instrumental variables. Summary-level data regarding the components of sarcopenia. Were obtained from the UK Biobank. Inverse variance weighted (IVW) as the primary method was used for Mendelian randomization (MR) analysis. We also use four models, weighted median, MR-Egger regression, Maximum likelihood, and Penalised weighted median, as supplementary methods to IVW. The MR-Egger intercept test, Cochran's Q test, and "leave-one-out" sensitivity analysis were performed to evaluate the horizontal pleiotropy, heterogeneities, and stability of the causal association between Hcy levels and the components of sarcopenia. Results: The IVW-MR analysis suggested significant negative associations of increased plasma Hcy levels with grip strength (right: effect = -0.036, SE = 0.032, p = 5.53E-4; left: effect = -0.045, SE = 0.010, p = 1.45E-5), walking pace (effect = -0.038, SE = 0.011, p = 3.18E-4), and ALM (effect = -0.058, 0.013, p = 1.03E-5). However, there were no significant associations of decreased plasma Hcy levels with grip strength (right: effect = 0.005, SE = 0.021, p = 0.82; left: effect = -0.006, SE = 0.014, p = 0.64), walking pace (effect = 0.01, 0.020, p = 0.61), or ALM (effect = -0.034, SE = 0.018, p = 0.06).The accuracy and robustness of these findings were confirmed by sensitivity tests. Conclusion: Increased circulating Hcy levels were associated with lower grip strength, slower walking pace, and decreased ALM.