Serum Cholesterol Levels within the High Normal Range Are Associated with Better Cognitive Performance among Chinese Elderly

An impact of lipid profile and lipid lowering drugs on ≥70 year olds of an upper socioeconomic class: a retrospective cohort study

BACKGROUND

Life expectancy has greatly increased, generating an improvement in screening programs for disease prevention, lifesaving drugs and medical devices. The impact of lowering low-density lipoprotein cholesterol (LDL-C) in the very elderly is not well-established. Our aim was to explore the association of LDL-C, high density lipoprotein cholesterol (HDL-C) and lipid lowering drugs (LLDs) on cognitive decline, malignancies and overall survival.

METHODS

This was a retrospective cohort study. Our study comprised 1498 (72.7%) males and 561 (27.3%) females, aged ≥70 who had attended the Institute for Medical Screening (IMS), Sheba Medical Center, Israel at least twice during 2013-2019. Data were obtained from the computerized database of the IMS. A manual quality control to identify potential discrepancies was performed.

RESULTS

Overall, 6.3% of the subjects treated with LLDs (95/1421) versus 4.2% not treated (28/638), cognitively declined during the study years. No statistically significant effects of LDL-C, HDL-C and LLDs on cognitive decline were observed after correcting for age, prior stroke and other vascular risk factors. With regard to cancer, after adjusting for confounders and multiple inferences, no definite relationships were found.

CONCLUSIONS

This analysis of an elderly, high socioeconomic status cohort suggests several relationships between the use of LLDs and health outcomes, some beneficial, especially, with regard to certain types of cancer, but with a higher risk of cognitive decline. Further studies are warranted to clarify the health effects of these medications in the elderly.

Development and validation of a clinical model (DREAM-LDL) for post-stroke cognitive impairment at 6 months

Introduction: This multicenter, retrospective study assessed the prevalence of post-stroke cognitive impairment (PSCI) 6 months after acute ischemic stroke (AIS) and its risk factors to build a bedside early predictive model for PSCI using the Montreal Cognitive Assessment (MoCA).

Methods: Records of consecutive patients with AIS treated at 4 stroke centers in Shanghai had MoCA assessments within 2 weeks after AIS onset and 6 months later were reviewed. Prevalence of PSCI (MoCA<22) was calculated and risk factors were identified by multivariate logistic regression analysis. The modeling and validation and identified risk factors were included in a predictive model using multivariate regression.

Results: There were 383 patients included and prevalence of PSCI 6 months after AIS was 34.2%, significantly lower than prevalence of patients with acute cognitive impairment (49.6%). Aging, less education, higher glucose level and severe stroke were PSCI risk factors, while level of low-density lipoprotein cholesterol (LDL-C) had a paradox effect on the risk of PSCI. 40.0% of the patients with cognitive impairment at acute phase reverted to normal, and patients with LDL-C 1.8-2.5 mmol/L were more likely to revert. The predictive model we built, DREAM-LDL (Diabetes [fasting blood glucose level], Rating [NIHSS], level of Education, Age, baseline MoCA and LDL-C level), had an AUROC of 0.93 for predicting PSCI at 6 months.

Conclusion: PSCI was common among AIS patients 6 months after AIS. We provided a practical tool to predict PSCI based on MoCA and risk factors present during acute phase of AIS.

Disrupted Topological Organization of Functional Networks in Asymptomatic Carotid Plaque Without Significant Carotid Stenosis: A Resting-State fMRI Study

Purpose: Previous studies have found that there are significant changes in functional network properties for patients with moderate to severe carotid artery stenosis. Our study aimed to explore the topology properties of brain functional network in asymptomatic patients with carotid plaque without significant stenosis.

Methods: A total of 61 asymptomatic patients with carotid plaque (mean age 61.79 ± 7.35 years) and 25 healthy control subjects (HC; 58.12 ± 6.79 years) were recruited. General data collection, carotid ultrasound examination and resting state functional magnetic resonance imaging were performed on all subjects. Graph-theory was applied to examine the differences in the brain functional network topological properties between two groups.

Results: In the plaque group, E_loc(P = 0.03), γ (P = 0.01), and σ (P = 0.01) were significantly higher than in the HC group. The degree centrality of left middle frontal gyrus and the nodal efficiency of left middle frontal gyrus and right inferior parietal angular gyrus were significantly higher in the plaque group than in HC. The degree centrality and betweenness centrality of right middle temporal gyrus, as well as the nodal efficiency of right middle temporal gyrus, were significantly lower in the plaque group than in HC.

Conclusions: The brain functional networks of patients with carotid plaques differ from those of healthy controls. Asymptomatic patients with carotid plaques exhibit increased local and global connectivity, which may reflect subtle reorganizations in response to early brain damage.

Long-Term Increase in Cholesterol Is Associated With Better Cognitive Function: Evidence From a Longitudinal Study

Background: Higher visit-to-visit cholesterol has been associated with cognitive decline. However, the association between long-term increase or decrease in cholesterol and cognitive decline remains unclear. Methods: A total of 4,915 participants aged ≥45 years with normal cognition in baseline were included. The participants were divided into four groups, namely low-low, low-high, high-low, and high-high, according to the diagnostic thresholds of total cholesterol (TC), non-high-density lipoprotein cholesterol (NHDL-C), low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol (HDL-C) after 4 years of follow-up. Cognitive function was assessed by episodic memory and mental intactness. Binary logistic regression was used to analyse the association of cholesterol variation with cognitive decline. Results: Among the participants, 979 (19.9%) experienced global cognitive decline. The odds ratio (OR) of global cognitive and memory function decline were remarkably lower in participants in the low-high NHDL-C group than those in the low-low group [OR and 95% confidence interval (CI): 0.50 [0.26-0.95] for global cognitive decline, 0.45 [0.25-0.82] for memory function decline]. The lower OR was also significant in females (OR [95% CI]: 0.38 [0.17-0.87] for global cognitive decline; 0.44 [0.19-0.97] for memory function decline) and participants without cardiovascular disease (OR [95% CI]: 0.31 [0.11-0.87] for global cognitive decline; 0.34 [0.14-0.83] for memory function decline). The increases in other cholesterol were also negatively associated with the risk of cognitive decline although not significantly. Conclusions: A longitudinal increase in NHDL-C may be protective for cognition in females or individuals without cardiovascular disease.

Longitudinal trajectories of metabolic syndrome on different neurocognitive domains: a cohort study from the Taiwan biobank

Metabolic syndrome (MetS) brings considerable effects on cognitive function, but trajectories within remain unclear. We investigated the interactions between distinct MetS components and cognitive domains. A total of 5693 participants from the Taiwan biobank during 2008–2018 were enrolled. Participants were classified as either normal or as having MetS at two time points; i.e., study entry and follow-up. At both the time points, cognitive evaluations using the Mini-Mental State Examination (MMSE) were conducted. The hazard ratios (HRs) of mild cognitive impairment (MCI) and dementia were higher in participants meeting more diagnostic components of MetS. Of the five criteria of MetS, three were significantly associated with MCI and dementia: high blood pressure (MCI: HR = 1.203, p < 0.001; dementia: HR = 1.345, p < 0.001), abdominal obesity (MCI: HR = 1.137, p = 0.006; dementia: HR = 1.442, p < 0.001), and low high-density lipoprotein (HDL) level (MCI: HR = 1.149, p = 0.007; dementia: HR = 1.364, p < 0.001). Of the cognitive domains measured, three were significantly associated with MetS; namely, orientation, language, and visuospatial abilities. Participants who were initially diagnosed with MetS but were normal at follow-up had an HR of 1.374 for dementia (p = 0.019), which was beyond our expectations. The undiminished risk of cognitive decline in subjects returning to normal status illustrated that neural injury caused by MetS takes a long time to get repaired. Consequently, earlier detection and management of adjustable risk factors of MetS should be encouraged to minimize the damage.

The Role of BMI and Blood Pressure in the Relationship Between Total Cholesterol and Disability in Chinese Centenarians: A Cross-Sectional Study

Background: Lower serum lipid metabolism might be associated with the decline of activity of daily living in the extreme longevity group. However, studies on models and possible paths of this correlation between total cholesterol (TC) and disability in centenarians are scarce. The aim of this study was to verify this correlation and explore the mediating effect of BMI and blood pressure on this relationship in Hainan centenarians.

Methods: We conducted a cross-sectional analysis of 1002 centenarians from the China Hainan Centenarians Cohort Study (CHCCS). Data on demographics, anthropometry data, lifestyle, and TC levels were collected through interviews, physical examinations, and laboratory tests. The Barthel index and Lawton index, measuring the disability status, were used to estimate the activity of daily living (ADL) and instrumental activity of daily living (IADL). A multivariable logistic regression model was used to explore the correlation between disability and TC levels. Mediation analyses were used to explore the both direct and indirect effects of TC level on disability.

Results: After adjusting for covariates, with 1 mmol/L increment in TC, the adjusted odds ratios (ORs) of ADL severe disability and ADL moderate & severe disability were 0.789(95%CI: 0.650–0.959) and 0.822(95%CI: 0. 0.699–0.966), respectively. There was a significant declining trend in the prevalence of different types of disability with increment in TC. The correlation was more pronounced among Hainan female centenarians. In the analysis of mediating effect among the female population, BMI significantly mediated the effect of TC levels on different types of disability. BMI and SBP, as chain mediators, multiply and chain mediated the effect of TC levels on IADL.

Conclusion: Low TC levels might be correlated with a higher frequency of disability in female centenarians, and this correlation might be mediated by BMI and blood pressure.

Effect of Combined Antihypertensive and Lipid-Lowering Therapies on Cognitive Function: A New Treatment Strategy?

Risk factors for cardiovascular disease such as hypertension and hyperlipidemia are associated with cognitive decline. However, there is still no clear evidence that the use of antihypertensive or lipid-lowering therapy can prevent or delay cognitive decline or development of dementia. To provide a reference for clinical treatment, we analyzed the potential mechanisms of cognitive dysfunction induced by hypertension and hyperlipidemia, the clinical research and controversy of antihypertensive and lipid-lowering therapies on cognitive function, and the clinical value of combined antihypertensive and lipid-lowering therapy. It is currently believed that hypertension and elevated blood cholesterol levels in middle-aged people may be related to cognitive impairment or dementia in the elderly. Some studies suggest that intensive antihypertensive or lipid-lowering therapies are better than standard antihypertensive or lipid-lowering therapy, yet further tests are needed to confirm their effects on cognitive function. Actively controlling potential risk factors from middle age may be important for Alzheimer's disease (AD) prevention.

Gene discovery for high-density lipoprotein cholesterol level change over time in prospective family studies

BACKGROUNDS AND AIMS

Several genes are known to contribute to the levels and metabolism of HDL-C, however, their protective effects in cardiovascular disease (CVD), healthy aging, and longevity are complex and poorly understood. It is also unclear if these genes predict longitudinal HDL-C change. We aimed to identify loci influencing HDL-C change.

METHODS

We performed a genome-wide association study (GWAS) with harmonized HDL-C and imputed genotype in three family-based studies recruited for exceptional survival (Long Life Family Study), from community-based (Framingham Heart Study) and enriched for CVD (Family Heart Study). In 7738 individuals with at least 2 visits, we employed a growth curve model to estimate the random linear trajectory parameter of age-sex-adjusted HDL-C for each person. GWAS was performed using a linear regression model on HDL-C change accounting for kinship correlations, population structure, and differences among studies.

RESULTS

We identified a novel association for HDL-C with GRID1 (p = 5.43 × 10^-10), which encodes a glutamate receptor channel subunit involved in synaptic plasticity. Seven suggestive novel loci (p < 1.0 × 10^-6; MBOAT2, LINC01876-NR4A2, NTNG2, CYSLTR2, SYNE2, CTXND1-LINC01314, and CYYR1) and a known lipid gene (ABCA10) showed associations with HDL-C change. Two additional sex-specific suggestive loci were identified in women (DCLK2 and KCNJ2). Several of these genetic variants are associated with lipid-related conditions influencing cardiovascular and metabolic health, have predictive regulatory function, and are involved in lipid-related pathways.

CONCLUSIONS

Modeling longitudinal HDL-C in prospective studies, with differences in healthy aging, longevity and CVD risk, contributed to gene discovery and provided insights into mechanisms of HDL-C regulation.

Higher Normal Levels of Triglyceride and Low and High-Density Lipoprotein Cholesterol Might Have a Protective Effect Against Activities of Daily Living Disability Within Chinese Female Centenarians: A Cross-Sectional, Complete Sample Study

Background and Objective

Activities of daily living (ADL) disability seriously affects the quality of life in the elderly. This study aims to examine the prevalence of ADL disability and its possible correlation with lipid profile indicators (LDL-C, TG and HDL-C) among female centenarians in Hainan, China.

Methods

A cross-section of complete sample study including 822 female centenarians was conducted from the China Hainan Centenarians Cohort Study (CHCCS) from June 2014 to December 2016. Barthel index was used to estimate ADL disability and multivariate logistic regression model was used to explore the relationship between lipid profile indicator and ADL disability.

Results

A total of 822 female centenarians were recruited in Hainan province, and the median age was 102 (IQR: 101–104) years, and 244 (29.7%) centenarians had ADL disability. After adjustment, 1 mmol/L increment in LDL-C, TG and HDL-C were associated with 26.4% (aOR=0.736, 95% CI:0.592–0.915), 29.8% (aOR=0.702, 95% CI:0.521–0.948) and 60.5% (aOR=0.395, 95% CI:0.257–0.610) decline in ADL disability of female centenarian, respectively. The prevalence of ADL disability showed downward trend with the increase of the quintile of LDL-C, TG and HDL-C (P_trend<0.05). Increment of HDL-C levels had the strongest protective effect against ADL disability.

Conclusion

We concluded that a new possible association of higher normal lipid profile indicators, especially HDL-C, might have a protective effect on ADL disability among female centenarians.

Revealing a Novel Landscape of the Association Between Blood Lipid Levels and Alzheimer's Disease: A Meta-Analysis of a Case-Control Study

Objectives: Blood lipid profiles have been ambiguously reported as biomarkers of AD in recent years. This study was conducted to evaluate the correlation between blood lipid levels and AD in later-life and to explore the effectiveness and reliability of blood lipid profiles as biomarkers of AD.

Methods: Database searching was conducted using PubMed, the Cochrane Library, EMBASE, and Medline. This study was designed following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) criteria. Review Manager 5.3 (RevMan 5.3) software was adopted to perform meta-analysis evaluating the standard mean difference (SMD) with its 95% confidence intervals (CI).

Results: A total of 5,286 participants were enrolled from 27 case–control studies in this meta-analysis. The pooled results demonstrated that total cholesterol (TC) level was significantly associated with AD in late-life (SMD = 0.17, 95% CI: [0.01, 0.32], P = 0.03), especially in the subgroup under 70 years old (SMD: 0.45, 95% CI: [0.11, 0.79], P = 0.01) and the subgroup of Western population (SMD: 0.29, 95% CI: [0.04, 0.53], P = 0.02). In the subgroup under 70 years old, the high-density lipoprotein cholesterol (HDL-C) level (SMD = −0.50, 95% CI: [−0.76, −0.25], P = 0.0001) and the low-density lipoprotein cholesterol (LDL-C) level (SMD = 0.59, 95% CI: [0.02, 1.16], P = 0.04) in the AD group were significantly lower and higher than in the control group, respectively. In the subgroup with a sample size larger than 100 subjects, the LDL-C level was significantly higher in AD patients than in the control elderly group (SMD = 0.31, 95% CI: [0.05, 0.56], P = 0.02). There was no significant association between triglyceride (TG) levels and AD in later-life (SMD = −0.00, 95% CI: [−0.12, 0.12], P = 1.00).

Conclusion: TC can be a new predictive biomarker of AD or cognitive decline in later-life. Increased TC levels are found to be associated with an elevated risk of AD. Decreased HDL-C levels and increased LDL-C levels may relate to an elevated risk of AD in subjects aged 60–70. Further comprehensive researches will be necessary in the future.

Relationships between dietary nutrients intake and lipid levels with functional MRI dorsolateral prefrontal cortex activation

Background

Dorsolateral prefrontal cortex (DLPFC) is a key node in the cognitive control network that supports working memory. DLPFC dysfunction is related to cognitive impairment. It has been suggested that dietary components and high-density lipoprotein cholesterol (HDL-C) play a vital role in brain health and cognitive function.

Purpose

This study aimed to investigate the relationships between dietary nutrient intake and lipid levels with functional MRI (fMRI) brain activation in DLPFC among older adults with mild cognitive impairment.

Participants and methods

A total of 15 community-dwelling older adults with mild cognitive impairment, aged ≥60 years, participated in this cross-sectional study at selected senior citizen clubs in Klang Valley, Malaysia. The 7-day recall Diet History Questionnaire was used to assess participants’ dietary nutrient intake. Fasting blood samples were also collected for lipid profile assessment. All participants performed N-back (0- and 1-back) working memory tasks during fMRI scanning. DLPFC (Brodmann’s areas 9 and 46, and inferior, middle, and superior frontal gyrus) was identified as a region of interest for analysis.

Results

Positive associations were observed between dietary intake of energy, protein, cholesterol, vitamins B6 and B12, potassium, iron, phosphorus, magnesium, and HDL-C with DLPFC activation (P<0.05). Multivariate analysis showed that vitamin B6 intake, β=0.505, t (14)=3.29, P=0.023, and Digit Symbol score, β=0.413, t (14)=2.89, P=0.045; R²=0.748, were positively related to DLPFC activation.

Conclusion

Increased vitamin B6 intake and cognitive processing speed were related to greater activation in the DLPFC region, which was responsible for working memory, executive function, attention, planning, and decision making. Further studies are needed to elucidate the mechanisms underlying the association.

Incidence and Comorbidity of Dementia with Lewy Bodies: A Population-Based Cohort Study

Background and Aims

Dementia with Lewy bodies (DLB) is the third most common form of dementia. Epidemiological studies of DLB in Taiwan are scarce. In this study, we estimated the incidence of DLB and comorbidity in the population of Taiwan.

Methods

Data were obtained from the Taiwan National Health Insurance Research Database (NHIRD). DLB patients between 2000 and 2013 were enrolled in assessments of incidence and comorbidity.

Results

The incidence of DLB was shown to be 7.10 per 100,000 person-years (95% CI = 6.63–7.59), which increased with age. The average age at diagnosis was 76.3, and this was higher for males than for females. The comorbidity rates of hypertension and hyperlipidemia in DLB patients were higher in females than in males.

Conclusions

Epidemiologic data from large-scale retrospective studies is crucial to the prevention of DLB.

Effects of Plasma Lipids and Statins on Cognitive Function

OBJECTIVE:

Dementia is the fourth most common cause of death in developed countries. The relationship between plasma lipids and cognitive function is complex and controversial. Due to the increasing life expectancy of the population, there is an urgent need to control vascular risk factors and to identify therapies to prevent and treat both cognitive impairment and dementia. Here, we reviewed the effects of plasma lipids and statins on cognitive function.

DATA SOURCES:

We searched the PubMed database for research articles published through November 2017 with key words including "plasma lipids," "hyperlipidemia," "hypercholesterolemia," "statins," and "cognition function."

STUDY SELECTION:

Articles were retrieved and reviewed to analyze the effects of plasma lipids and statins on cognitive function and the mechanisms underlying these effects.

RESULTS:

Many studies have examined the relationship between plasma lipids and cognitive function, but no definitive conclusions can be drawn. The mechanisms involved may include blood-brain barrier injury, the influence on small blood vessels in the brain, the influence on amyloid deposition, and a neuroprotective effect. To date, most studies of statins and cognition have been observational, with few randomized controlled trials. Therefore, firm conclusions regarding whether mid- or long-term statin use affects cognition function and dementia remain elusive. However, increasing concern exists that statins may be a causative factor for cognitive problems. These adverse effects appear to be rare and likely represent a yet-to-be-defined vulnerability in susceptible individuals.

CONCLUSIONS:

The association between plasma lipids and cognition, the mechanism of the influence of plasma lipids on cognitive function, and the association between statins and cognitive function are complex issues and currently not fully understood. Future research aimed at identifying the mechanisms that underlie the effects of plasma lipids and statins on cognition will not only provide important insight into the causes and interdependencies of cognitive impairment and dementia, but also inspire novel strategies for treating and preventing these cognitive disorders.

Sex-specific nonlinear associations between serum lipids and different domains of cognitive function in middle to older age individuals

To examine how serum lipids relates to specific cognitive ability domains between the men and women in Chinese middle to older age individuals. A complete lipid panel was obtained from 1444 individuals, ages 50-65, who also underwent a selection of cognitive tests. Participants were 584 men and 860 women from Linyi city, Shandong province. Multiple linear regression analyses examined serum lipids level as quadratic predictors of sex-specific measure of performance in different cognitive domains, which were adjusted for sociodemographic and lifestyle characteristics. In men, a significant quadratic effect of total cholesterol (TC) was identified for Digit Symbol (B = -0.081, P = 0.044) and also quadratic effect of low density lipoprotein-cholesterol (LDL-C) was identified for Trail Making Test B (B = -0.082, P = 0.045). Differently in women, there were significant quadratic associations between high density lipoprotein-cholesterol (HDL-C) and multiple neuropsychological tests. The nonlinear lipid-cognition associations differed between men and women and were specific to certain cognitive domains and might be of potential relevance for prevention and therapy of cognitive decline.