Association among plasma lactate, systemic inflammation, and mild cognitive impairment: a community-based study

Associations of serum lactate and lactate clearance with delirium in the early stage of ICU: a retrospective cohort study of the MIMIC-IV database

Aim

This study aimed to investigate the associations of serum lactate level [within and after 24 h of the intensive care unit (ICU) admission] and lactate clearance rate with delirium and assess associations of lactate and lactate clearance rate with 30-day mortality in delirium patients.

Methods

Data in this retrospective cohort study were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database in 2012-2019. The associations of lactate and lactate clearance rate with delirium were explored through univariable and multivariable logistic regression analyses, whereas the associations of lactate and lactate clearance rate with 30-day mortality in delirium patients were investigated using univariable and multivariable Cox regression analyses. Subgroup analysis was performed for age, gender, sepsis, hypertension, sedative drug, ventilation, antibiotic drug, vasopressors, and the Sequential Organ Failure Assessment (SOFA) score. The evaluation indexes were odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs).

Results

Among 7,812 (14.58%) eligible participants, 4,338 (8.19%) had delirium and 1,903 (24.36%) died within 30 days. After adjusting for covariates, patients with lactic acidosis (lactate level > 5 mmol/L and PH < 7.35) at T0 (within 24 h of the ICU admission) had higher odds of delirium (OR = 1.235, 95%CI: 1.105-1.382). Hyperlactatemia (lactate level 2-5 mmol/L and PH > 7.35) at T1 (after 24 h of the ICU admission) was also associated with higher odds of delirium (OR = 1.277, 95%CI: 1.126-1.447). Lactate clearance rate > 50% was linked to lower odds of delirium (OR = 0.705, 95%CI: 0.613-0.811), and this relationship was also observed in ≥65 years old, female, male, non-sepsis, sepsis, non-hypertension, non-sedative drug use, sedative drug use, ventilation, antibiotic drug use, use of vasopressors, and different SOFA score subgroups (all p < 0.05). Additionally, hyperlactatemia and lactic acidosis (whether at T0 or T1) may be potential risk factors for 30-day mortality in delirium patients, whereas lactate clearance rate ≥ 0 had a potential protective effect on 30-day mortality (all p < 0.05).

Conclusion

Higher serum lactate levels in the early stage of the ICU were associated with a higher risk of delirium and subsequent mortality. Measures taken to increase the lactate clearance rate are necessary to reduce potential delirium or mortality risk in clinical settings. However, more evidence from prospective studies is needed to verify these findings.

Roles of Omega-3 Polyunsaturated Fatty Acids in Managing Cognitive Impairment in Chronic Obstructive Pulmonary Disease: A Review

Chronic obstructive pulmonary disease (COPD) contributes significantly to the death of people worldwide, especially the elderly. An essential feature of COPD is pulmonary inflammation, which results from long-term exposure to noxious substances from cigarette smoking and other environmental pollutants. Pulmonary inflammatory mediators spill over to the blood, leading to systemic inflammation, which is believed to play a significant role in the onset of a host of comorbidities associated with COPD. A substantial comorbidity of concern in COPD patients that is often overlooked in COPD management is cognitive impairment. The exact pathophysiology of cognitive impairment in COPD patients remains a mystery; however, hypoxia, oxidative stress, systemic inflammation, and cerebral manifestations of these conditions are believed to play crucial roles. Furthermore, the use of medications to treat cognitive impairment symptomatology in COPD patients has been reported to be associated with life-threatening adverse effects, hence the need for alternative medications with reduced side effects. In this Review, we aim to discuss the impact of cognitive impairment in COPD management and the potential mechanisms associated with increased risk of cognitive impairment in COPD patients. The promising roles of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) in improving cognitive deficits in COPD patients are also discussed. Interestingly, ω-3 PUFAs can potentially enhance the cognitive impairment symptomatology associated with COPD because they can modulate inflammatory processes, activate the antioxidant defence system, and promote amyloid-beta clearance from the brain. Thus, clinical studies are crucial to assess the efficacy of ω-3 PUFAs in managing cognitive impairment in COPD patients.

Association of Osteoarthritis and Functional Limitations With Cognitive Impairment Among Older Adults in the United States

Objective: Given overlapping pathophysiology, this study sought to assess the association between osteoarthritis (OA), functional impairment, and cognitive impairment in the aging population. Methods: The National Health and Nutrition Examination Survey was used to identify participants >60 years of age. We analyzed multivariable associations of grouped participants that underwent cognitive function testing using linear and logistic regression, adjusting for sex, age, race, and ethnicity. Results: Of 2776 identified participants representing a population of 50,242,917, 40% did not report OA or functional limitations; 21% had OA but not functional limitations; 15% did not have OA but had functional limitations; 17% had OA and related functional limitations; and 7% had OA and non-arthritic functional limitations. OA was not independently associated with cognitive impairment. Contrarily, functional limitations were associated with cognitive impairment regardless of OA diagnosis. Discussion: Cognitive impairment is not associated with OA, but rather functional limitations, potentially guiding future intervention.

Muscle-Brain crosstalk in cognitive impairment

Sarcopenia is an age-related, involuntary loss of skeletal muscle mass and strength. Alzheimer's disease (AD) is the most common cause of dementia in elderly adults. To date, no effective cures for sarcopenia and AD are available. Physical and cognitive impairments are two major causes of disability in the elderly population, which severely decrease their quality of life and increase their economic burden. Clinically, sarcopenia is strongly associated with AD. However, the underlying factors for this association remain unknown. Mechanistic studies on muscle-brain crosstalk during cognitive impairment might shed light on new insights and novel therapeutic approaches for combating cognitive decline and AD. In this review, we summarize the latest studies emphasizing the association between sarcopenia and cognitive impairment. The underlying mechanisms involved in muscle-brain crosstalk and the potential implications of such crosstalk are discussed. Finally, future directions for drug development to improve age-related cognitive impairment and AD-related cognitive dysfunction are also explored.

Neurobiological Highlights of Cognitive Impairment in Psychiatric Disorders

This review is focused on several psychiatric disorders in which cognitive impairment is a major component of the disease, influencing life quality. There are plenty of data proving that cognitive impairment accompanies and even underlies some psychiatric disorders. In addition, sources provide information on the biological background of cognitive problems associated with mental illness. This scientific review aims to summarize the current knowledge about neurobiological mechanisms of cognitive impairment in people with schizophrenia, depression, mild cognitive impairment and dementia (including Alzheimer's disease).The review provides data about the prevalence of cognitive impairment in people with mental illness and associated biological markers.

Poor sleep quality is negatively associated with low cognitive performance in general population independent of self-reported sleep disordered breathing

BACKGROUND

Sleep disordered breathing (SDB) plays a significant role in both sleep quality and cognition and whether it has an impact on the relationship between above two factors remains to be clear. The study aimed to explore the association between sleep quality and cognitive performance in general population by considering influence of sleep disordered breathing (SDB).

METHODS

In this cross-sectional study, we enrolled subjects aged ≥ 18 years using a multi-stage random sampling method. Cognitive status was assessed using Mini Mental State Examination (MMSE) questionnaire, sleep quality using Pittsburgh Sleep Quality Index (PSQI) and SDB was assessed using No-SAS scale, respectively. Multi-variable logistic regression was applied to examine the association of sleep quality and cognitive performance. Subgroup analyses were performed in different age groups, and in those with and without SDB.

RESULTS

Finally, 30,872 participants aged 47.5 ± 13.8 years with 53.5% women were enrolled, of whom 32.4% had poor sleep quality and 18.6% had low cognitive performance. Compared with good sleepers, subjects with poor sleep quality exhibited significantly higher presence of low cognitive performance (23.7% vs 16.2%, P < 0.001). Poor sleepers revealed 1.26 (95%CI: 1.16,1.36), 1.26 (1.08,1.46) and 1.25 (1.14,1.37) fold odds for low cognitive performance in general population and in subjects with and without self-reported SDB respectively. Stratified by age and SDB, the association was observed in young and middle-aged group without SDB (OR = 1.44, 95%CI: 1.30,1.59) and in the elderly group with SDB (OR = 1.30, 95%CI: 1.07,1.58).

CONCLUSIONS

Sleep quality is in a negative association with cognitive performance in general population independent of SDB, implying improvement of sleep disturbances is a potential objective of intervention strategies for cognitive protection at population level.

Evidence of Brain Alterations in Noncerebral Falciparum Malaria

BACKGROUND

Cerebral malaria in adults is associated with brain hypoxic changes on magnetic resonance (MR) images and has a high fatality rate. Findings of neuroimaging studies suggest that brain involvement also occurs in patients with uncomplicated malaria (UM) or severe noncerebral malaria (SNCM) without coma, but such features were never rigorously characterized.

METHODS

Twenty patients with UM and 21 with SNCM underwent MR imaging on admission and 44-72 hours later, as well as plasma analysis. Apparent diffusion coefficient (ADC) maps were generated, with values from 5 healthy individuals serving as controls.

RESULTS

Patients with SNCM had a wide spectrum of cerebral ADC values, including both decreased and increased values compared with controls. Patients with low ADC values, indicating cytotoxic edema, showed hypoxic patterns similar to cerebral malaria despite the absence of deep coma. Conversely, high ADC values, indicative of mild vasogenic edema, were observed in both patients with SNCM and patients with UM. Brain involvement was confirmed by elevated circulating levels of S100B. Creatinine was negatively correlated with ADC in SNCM, suggesting an association between acute kidney injury and cytotoxic brain changes.

CONCLUSIONS

Brain involvement is common in adults with SNCM and a subgroup of hospitalized patients with UM, which warrants closer neurological follow-up. Increased creatinine in SNCM may render the brain more susceptible to cytotoxic edema.

Association between 24-h urinary sodium to potassium ratio and mild cognitive impairment in community-based general population

OBJECTIVE

To explore the relationship between parameters of Na and K excretion using 24-h urine sample and mild cognitive impairment (MCI) in general population.

DESIGN

This is a cross-sectional study.

SETTING

Community-based general population in Emin China.

PARTICIPANTS

Totally, 1147 subjects aged ≥18 years were selected to complete the study, with a multistage proportional random sampling method. Cognitive status was assessed with Mini Mental State Examination (MMSE) questionnaire and timed 24-h urine specimens were collected. Finally, 561 participants aged ≥35 years with complete urine sample and MMSE data were included for the current analysis and divided into groups by tertiles of 24-h urinary sodium to potassium ratio (24-h UNa/K) as lowest (T1), middle (T2) and highest (T3) groups.

RESULTS

The MMSE score was significantly lower in T3, compared with the T1 group (26·0 v. 25·0, P = 0·002), and the prevalent MCI was significantly higher in T3 than in T1 group (11·7 % v. 25·8 %, P < 0·001). In multiple linear regression, 24-UNa/K (β: -0·184, 95 % CI -0·319, -0·050, P = 0·007) was negatively associated with MMSE score. In multivariable logistic regression, compared with T1 group, 24-h UNa/K in the T2 and T3 groups showed 2·01 (95 % CI 1·03, 3·93, P = 0·041) and 3·38 (95 % CI 1·77, 6·44, P < 0·001) fold odds for presence of MCI, even after adjustment for confounders. More augmented results were demonstrated in sensitivity analysis by excluding individuals taking anti-hypertensive agents.

CONCLUSIONS

Higher 24-h UNa/K is in an independent association with prevalent MCI.

Association of Hypertension with Mild Cognitive Impairment in Population from Less-Developed Areas of Multiethnic Northwest China

BACKGROUND

Relationship between hypertension and mild cognitive impairment (MCI) remains undetermined in population from less-developed regions. We aimed to explore whether hypertension is associated with MCI in this specific population.

METHODS

In this cross-sectional study, we enrolled subjects aged ≥18 years using multistage random sampling from Emin, China, in 2019. Participants underwent questionnaires and data collection including mini-mental state examination (MMSE) and blood pressure measurement.

RESULTS

Finally, 31,329 subjects were included, with 11,270 hypertensives. Compared with normotensive subjects, hypertensives were characterized by significantly older age (55.19 ± 12.25 vs. 43.26 ± 12.71), more men (52.5% vs. 42.9%), low education attainment (≤primary education: 42.4% vs. 26.3%), more abdominal obesity (39.7% vs. 19.1%), poor sleep quality (39.1% vs. 28.7%), and chronic kidney disease (6.6% vs. 3.4%, p for all <0.001). Prevalence of MCI in hypertensives was significantly higher than that of normotensive subjects (24.3% vs. 15.6%, p < 0.001). Multivariate logistic regression analysis showed in a fully adjusted model that the odds for MCI were significantly increased in hypertensives than in normotensive population (OR = 1.19, 95% CI: 1.09, 1.30, p < 0.001) and independent of all the parameters studied including age, education level, and stroke. In the age-stratified regression model, presence of hypertension significantly increased the odds of MCI by 1.17-fold (95% CI: 1.03, 1.33, p = 0.020) and by 1.22-fold (95% CI: 1.04, 1.44, p = 0.016) in middle-aged and elderly population. Sensitivity analysis of excluding those with stroke history showed that hypertension was still a risk factor for MCI in total, middle-aged, and elderly population.

CONCLUSION

Hypertension is in independent negative association with MCI in middle-aged and elderly population from underdeveloped regions.

Blood pressure and cognitive decline over the course of 2 years in elderly people: a community-based prospective cohort study

BACKGROUND

Numerous studies have shown a significant association between blood pressure (BP) and cognition, but little is known about the effect of BP on the rate of cognitive decline.

AIMS

To investigate the relationship between blood pressure and the subsequent rate of cognitive decline in elderly people.

METHODS

Based on a prospective cohort that has been followed since 2014, we collected baseline blood pressures and other covariates in 7874 Chinese individuals aged 60 years or older, and followed their cognitive change using the Mini-Mental State Examination (MMSE) until Dec 31, 2016. Linear mixed-effects models were used to measure changes in MMSE scores over time in relation to blood pressure values, and in addition to the covariates, we included random effects for intercepts and slopes.

RESULTS

In the non-hypertension group, we observed that faster cognitive decline was associated with higher systolic blood pressure, lower diastolic blood pressure, lower mean arterial pressure, and higher pulse pressure. In the hypertension group, lower diastolic blood pressure, lower mean arterial pressure, and higher pulse pressure were associated with faster cognitive decline, but not systolic blood pressure.

CONCLUSION

Higher systolic blood pressure, lower diastolic blood pressure, lower mean arterial pressure, and higher pulse pressure accelerate the subsequent rate of cognitive decline in elderly people. The results of this study may help improve blood-pressure control strategies to prevent cognitive decline.

Interactions among endotoxin, uric acid, and lactate in relation to the risk of type 2 diabetes: A population-based study

BACKGROUND

Blood levels of endotoxin, uric acid (UA), or lactate (LAC) are associated with type 2 diabetes mellitus (T2DM). Thus, we explored the interactions among blood endotoxin, UA, and LAC levels and the risk of T2DM.

METHODS

This population-based cross-sectional study included 2520 Chinese adults. Fasting blood endotoxin, UA, and LAC levels were determined and the cut-off values were obtained from the receiver operating characteristic curve analysis. The study population was classified into two or four subgroups based on low or high, or both low and high levels of endotoxin, UA, and LAC, respectively.

RESULTS

The odds ratios (ORs) for T2DM (all P < .05) were higher in the high groups than the low groups of endotoxin, UA, or LAC, respectively. Participants in the groups with high levels of both endotoxin and UA, endotoxin and LAC, or UA and LAC, had 4.71 (95% CI 3.01-7.37), 5.13 (95% CI 3.29-7.99), or 3.73 (95% CI 2.34-5.94) times higher risk for T2DM compared to those in groups with low levels of both endotoxin and UA, endotoxin and LAC, or UA and LAC (all P < 0.05), respectively. In the interaction analysis, an interactive effect between endotoxin and UA (P < .05), or endotoxin and LAC (P < .05), but not UA and LAC, was observed that contributed to an increased risk of T2DM.

CONCLUSIONS

The interaction between levels of endotoxin and UA or levels of endotoxin and LAC was related to an increased risk of T2DM in the Chinese population.

Potential Fluid Biomarkers for the Diagnosis of Mild Cognitive Impairment

Mild cognitive impairment (MCI) is characterized by a level of cognitive impairment that is lower than normal for a person’s age, but a higher function than that that observed in a demented person. MCI represents a transitional state between normal aging and dementia disorders, especially Alzheimer’s disease (AD). Much effort has been made towards determining the prognosis of a person with MCI who will convert to AD. It is now clear that cerebrospinal fluid (CSF) levels of Aβ40, Aβ42, total tau and phosphorylated tau are useful for predicting the risk of progression from MCI to AD. This review highlights the advantages of the current blood-based biomarkers in MCI, and discusses some of these challenges, with an emphasis on recent studies to provide an overview of the current state of MCI.