Functional relationships between serum total cholesterol levels, executive control, and sustained attention

Cognitive profile in burning mouth syndrome versus mild cognitive impairment: A comparative study

OBJECTIVES

This study aims to assess and contrast cognitive and psychological aspects of patients with burning mouth syndrome (BMS-MCI) and geriatric patients (G-MCI) with mild cognitive impairment, focusing on potential predictors like pain, mood disorders, blood biomarkers, and age-related white matter changes (ARWMCs).

METHODS

The study enrolled 40 BMS-MCI and 40 geriatric G-MCI, matching them by age, gender, and educational background. Participants underwent psychological, sleepiness, and cognitive assessment including the Mini-Mental State Exam (MMSE), Trail Making Test (TMT), Corsi Block-Tapping Task, Rey Auditory Verbal Learning Test, Copying Geometric Drawings Test, Frontal Assessment Battery, and Digit Cancellation Test.

RESULTS

G-MCI patients exhibited higher ARWMCs scores in right (p = 0.005**) and left (p < 0.001**) temporal regions, which may relate to specific neurodegenerative processes. Conversely, BMS-MCI patients showed higher levels of depression and anxiety and lower MMSE scores(p < 0.001**), also struggling more with tasks requiring processing speed and executive function, as evidenced by their higher TMT-A scores (p < 0.001**).

CONCLUSIONS

The study highlights particular deficits in global cognition and processing speed for BMS-MCI. The influence of educational background, pain levels, cholesterol, sleep disturbances, and anxiety on these cognitive assessments underscores the need for personalized therapeutic strategies addressing both cognitive and emotional aspects of MCI.

Large-Scale Internetwork Functional Connectivity Mediates the Relationship between Serum Triglyceride and Working Memory in Young Adulthood

Previous research has demonstrated that serum lipid profile is associated with cognitive function as well as brain structure and function in middle-aged, elderly, and clinical populations. However, the nature and extent of lipids-brain-cognition relationships in young adulthood are largely unknown. In this study, 157 healthy young adults underwent resting-state functional MRI scans. Functional connectivity between and within 14 functional networks were calculated using independent component analysis. Peripheral venous blood samples were collected to measure serum lipids. Working memory was assessed using a 3-back task. Linear regression, correlation, and mediation analyses were conducted to test for potential associations between serum lipids, inter- and intranetwork functional connectivity, and working memory performance. We found that higher serum triglyceride (TG) level was correlated with stronger connectivity between left frontoparietal and ventral attention networks, between right frontoparietal and dorsal attention networks, between right frontoparietal and dorsal sensorimotor networks, between right frontoparietal and lateral visual networks, and between salience (SN) and ventral sensorimotor (vSMN) networks, as well as lower connectivity between posterior default mode and left frontoparietal networks, between left frontoparietal and medial visual networks, and between ventral attention and dorsal sensorimotor networks. In addition, higher SN-vSMN connectivity was related to lower 3-back accuracy. More importantly, the relationship between serum TG and 3-back accuracy was mediated by SN-vSMN connectivity. Our findings not only may expand existing knowledge regarding serum lipids-brain-cognition relations from the perspective of large-scale functional network organization but also may inform a translational conceptualization of how to improve cognitive function through regulating serum lipids.

Examining the Influence of Early Life Stress on Serum Lipid Profiles and Cognitive Functioning in Depressed Patients

Background

Early childhood adversity is a strong predictor of the development of major depressive disorder (MDD), but not all depressed patients experience early life stress (ELS). Cardio-metabolic diseases and cognitive deficits often coincide in MDD and worsen its course and outcome. Adverse childhood experiences have been associated with elevated risk for cardiovascular disease (CVD), but little is known on the impact of ELS on cardiovascular risk factors in MDD. Here, we examined MDD patients with and without ELS to explore the effects of ELS on serum lipid and lipoprotein levels and on cognitive performances of the patients.

Methods

Participants with a mean age of 35 years (18–55 years) were recruited from the university mental health clinic and general community. Three groups, matched in age, gender and lifestyle were examined: MDD patients with ELS (n = 21), MDD patients without ELS (n = 21), and healthy controls (n = 20). The following CVD risk factors were assessed: serum lipids (total cholesterol, triglycerides, high- and low-density lipoproteins), body mass index and exercise in a typical week. MDD severity was measured by the Beck Depression Inventory. Childhood Trauma Questionnaire was used to assess early life adversities. Executive functions and attentional processes were assessed by the Wisconsin Card Sorting and Conners’ Continuous Performance tests.

Results

Major depressive disorder patients with ELS had higher serum triglyceride and lower HDL-cholesterol concentrations compared to MDD patients without ELS. Linear regression analysis revealed that the severity of ELS had a significant negative association with HDL-cholesterol levels and significant positive associations with the serum levels of TG and TC/HDL-cholesterol index. We also found significant associations between some specific trauma types and lipid profiles. Finally, we could detect significant associations between depression severity and specific domains of the cognitive tests as well as between lipid profiles and certain domains of the Wisconsin Card Sorting Test. However, we could not detect any association between the severity of ELS and cognitive performance.

Conclusion

After controlling for depressive symptom severity and lifestyle variables, ELS was found to be a strong predictor of serum lipid alterations. Several, inter-correlated pathways may mediate the undesirable effects of ELS on the course and outcome of MDD.

Elevated levels of serum cholesterol are associated with better performance on tasks of episodic memory

We examined how serum cholesterol, an established risk factor for cerebrovascular disease (CVD), relates to cognitive function in healthy middle-older aged individuals with no neurologic or CVD history. A complete lipid panel was obtained from a cohort of one hundred twenty individuals, ages 43-85, who also underwent a comprehensive neuropsychological examination. In order to reduce the number of variables and empirically identify broad cognitive domains, scores from neuropsychological tests were submitted into a factor analysis. This analysis revealed three explainable factors: Memory, Executive Function and Memory/Language. Three separate hierarchical multiple regression analyses were conducted using individual cholesterol metrics (total cholesterol, low density lipoprotein; LDL, high density lipoprotein; HDL, and triglycerides), as well as age, education, medication status (lipid lowering agents), ApoE status, and additional risk factors for CVD to predict neuropsychological function. The Memory Factor was predicted by a combination of age, LDL, and triglyceride levels; both age and triglycerides were negatively associated with factor score, while LDL levels revealed a positive relationship. Both the Executive and Memory/Language factor were only explained by education, whereby more years were associated with better performance. These results provide evidence that individual cholesterol lipoproteins and triglycerides may differentially impact cognitive function, over and above other common CVD risk factors and ApoE status. Our findings demonstrate the importance of consideration of vascular risk factors, such as cholesterol, in studies of cognitive aging.

Lipid correlates of attentional impulsivity in first episode mania: results from an Indian population

BACKGROUND

Attentional/cognitive impulsivity has been demonstrated as being associated with an increased risk for suicide and other self-harming behaviors, along with a more severe course in patients with bipolar disorder. That an alteration of the various serum lipid fractions might be associated with increased impulsivity has been proposed in the past, but evidences are ambiguous and mainly based on western population data.

OBJECTIVE

The present study was aimed to analyze the attentional impulsivity and various serum lipid fractions in bipolar patients, from an Indian perspective.

MATERIALS AND METHODS

At presentation, 60 drug free/naïve first episode Mania patients were rated on the Barratt impulsiveness scale-version 11 and Young Mania Rating Scale; body mass index (BMI) was calculated and blood samples were analyzed for total cholesterol (TC), high density lipoproteins, low density lipoproteins and very low density lipoproteins (VLDL), triglycerides (TG) and apolipoproteins A1 and B.

RESULTS

The analysis revealed statistically significant negative correlation and inverse linear relationship between TC, TG, VLDL and BMI with attentional impulsivity.

CONCLUSION

The present study adds to the growing literature on a complex relationship between lipid fractions and attentional impulsivity. The findings present interesting insights into the possible substrates of human behavior at biochemical levels. The implications are many, including a need to introspect regarding the promotion of weight loss and cholesterol reduction programs in constitutionally vulnerable population.

Habitual fat intake predicts memory function in younger women

High intakes of fat have been linked to greater cognitive decline in old age, but such associations may already occur in younger adults. We tested memory and learning in 38 women (25 to 45 years old), recruited for a larger observational study in women with polycystic ovary syndrome. These women varied in health status, though not significantly between cases (n = 23) and controls (n = 15). Performance on tests sensitive to medial temporal lobe function (CANTABeclipse, Cambridge Cognition Ltd, Cambridge, UK), i.e., verbal memory, visuo-spatial learning, and delayed pattern matching (DMS), were compared with intakes of macronutrients from 7-day diet diaries and physiological indices of metabolic syndrome. Partial correlations were adjusted for age, activity, and verbal IQ (National Adult Reading Test). Greater intakes of saturated and trans fats, and higher saturated to unsaturated fat ratio (Sat:UFA), were associated with more errors on the visuo-spatial task and with poorer word recall and recognition. Unexpectedly, higher UFA intake predicted poorer performance on the word recall and recognition measures. Fasting insulin was positively correlated with poorer word recognition only, whereas higher blood total cholesterol was associated only with visuo-spatial learning errors. None of these variables predicted performance on a DMS test. The significant nutrient–cognition relationships were tested for mediation by total energy intake: saturated and trans fat intakes, and Sat:UFA, remained significant predictors specifically of visuo-spatial learning errors, whereas total fat and UFA intakes now predicted only poorer word recall. Examination of associations separately for monounsaturated (MUFA) and polyunsaturated fats suggested that only MUFA intake was predictive of poorer word recall. Saturated and trans fats, and fasting insulin, may already be associated with cognitive deficits in younger women. The findings need extending but may have important implications for public health.

Low cholesterol is a risk factor for attentional impulsivity in patients with mood symptoms

This study examined the relationship between cholesterol levels and impulsivity in a large sample of patients with mood symptoms. Three hundred and one patients with mood, anxiety, and personality disorders completed a battery of psychometric scales including the Barratt Impulsiveness Scale-Version 11 (BIS-11) and the Profile of Mood States (POMS). On the same day of psychometric assessment, blood samples were analyzed for total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C). Statistical analysis controlling for the confounding effects of age, gender, diagnosis, and current mood symptoms showed that lower TC levels were associated with increased attentional impulsivity. There was a weak linear correlation between TC and attentional impulsivity across the entire range of TC levels (110-295mg/dL) but a highly significant difference between participants with TC levels lower than 165mg/dL and the rest of the sample. The current study adds to the growing body of evidence pointing to the association between serum cholesterol and mental health. Considering that attentional impulsivity is a demonstrated risk factor for suicide, patients presenting with low cholesterol and mood symptoms may warrant increased clinical attention and surveillance.