Impaired cognitive performance in asymptomatic peripheral arterial disease: relation to C-reactive protein and D-dimer levels

Malnutrition, Depression, Poor Sleep Quality, and Difficulty Falling Asleep at Night Are Associated with a Higher Risk of Cognitive Frailty in Older Adults during the COVID-19 Restrictions

The COVID-19 restrictions, such as social isolation and disruption of daily routines, can have detrimental effects, including increased stress, anxiety, sleep disturbance, and physical and cognitive decline among older adults. This study aimed to examine the association between nutritional status, depression, sleep quality, falling asleep at night, and cognitive frailty (CF) among older Thai adults during the COVID-19 pandemic. This cross-sectional study included 408 older adults with an average age of 70.54 (5.49) years. CF was determined using Fried's frailty phenotype and the Montreal Cognitive Assessment Basic. The Mini Nutritional Assessment-Short Form, Pittsburgh Sleep Quality Index, and geriatric depression assessment were used for assessment. Multiple logistic regression analysis demonstrated that participants who were malnourished (OR 3.786; 95%CI 1.719-8.335), depressed (OR 5.003; 95%CI 2.399-10.434), had poor sleep quality (OR 1.613; 95%CI 1.041-2.500), and engaged in difficulty falling asleep (OR 1.809; 95%CI 1.022-3.203) had a higher risk of CF compared to those who did not exhibit these factors. Therefore, malnutrition, depression, poor sleep quality, and difficulty falling asleep were identified as risk factors for CF among older adults in Thailand linked to the impact of the COVID-19 pandemic. It is crucial to develop interventions to prevent CF resulting from the mentioned variables.

Relationship between serum homocysteine, fibrinogen, lipoprotein-a level, and peripheral arterial disease: a dose-response meta-analysis

AIM

At present, the relationship between serum homocysteine (Hcy), fibrinogen (FIB), lipoprotein-a (LPa), and PAD is uncertain, and there has been no meta-analysis to establish the dose-response relationship between their exposure levels and PAD.

METHODS AND RESULTS

Relevant literature published in PubMed, Embase, and Web of Science was retrieved. The robust error meta-regression method was used to assess the linear and non-linear dose-response relationship between exposure level and PAD risk. A total of 68 articles, involving 565,209 participants, were included. Combined with continuous variables, the serum Hcy, FIB, and LPa levels of PAD patients were significantly higher than those of healthy individuals. The odds ratios (ORs) of PAD for individuals with high Hcy, FIB, and LPa levels compared with those with low levels were 1.47, 1.14, and 1.76, respectively. The study also showed that circulating Hcy, FIB, and LPa were significantly elevated in patients with PAD compared with controls. The level of Hcy and the risk of PAD presented a U-shaped distribution. The nonlinear dose-response model showed that each 1 μmol/L increase in serum Hcy increased the risk of PAD by 7%. Similarly, for each 10 mg/dL FIB and 10 mg/dL LPa increases, the risk of PAD increased by 3% and 6%, respectively.

CONCLUSIONS

This meta-analysis provided evidence that elevated Hcy, PIB, and LPa levels may increase the risk of PAD, and the risk of PAD increases with the increase in serum exposure within a certain range. By controlling Hcy level, the incidence of PAD may be reduced to control the PAD growing epidemic.

TRIAL REGISTRATION NUMBER

PROSPERO (CRD42021250501), https://www.crd.york.ac.uk/prospero/.

Association of sleep quality and nap duration with cognitive frailty among older adults living in nursing homes

Background

Sleep status, including sleep quality and nap duration, may be associated with frailty and cognitive impairment in older adults. Older adults living in nursing homes may be more prone to physical and cognitive frailties. This study aimed to investigate the association between sleep quality and nap duration, and cognitive frailty among older adults living in nursing homes.

Methods

This study included 1,206 older adults aged ≥ 60 years from nursing homes in Hunan province, China. A simple frailty questionnaire (FRAIL scale) was used and Mini-Mental State Examination was conducted to assess physical frailty and cognitive impairment, respectively, to confirm cognitive frailty. The Pittsburgh Sleep Quality Index was used to assess the sleep quality. Nap duration was classified as follows: no, short (≤30 min), and long (>30 min) napping. Multinomial logistic regression was conducted to estimate the odds ratio (OR) and 95% confidence interval (CI).

Results

The prevalence of cognitive frailty among the older adults in nursing homes was 17.5%. Approximately 60.9% of the older adults had a poor sleep quality. Among the 1,206 participants, 43.9% did not take naps, 29.1% had short naps, and 26.9% had long naps. After adjusting for all covariates, poor sleep quality (OR 2.53; 95% CI 1.78-3.59; P < 0.001) and long nap duration (OR 1.77; 95% CI 1.19-2.64; P = 0.003) were associated with higher odds of cognitive frailty, but short nap duration (OR 0.60; 95% CI 0.40-0.89; P = 0.012) was associated with low prevalence of cognitive frailty.

Conclusion

Poor sleep quality and long nap duration are significantly associated with high risk of cognitive frailty among the older adults in nursing homes. Short nap duration was associated with low prevalence of cognitive frailty. However, these associations require further validation in older adults.

Clinical trial registration

https://osf.io/57hv8.

Microvascular dysfunction and neurovascular uncoupling are exacerbated in peripheral artery disease, increasing the risk of cognitive decline in older adults

Peripheral artery disease (PAD) is a vascular pathology with high prevalence among the aging population. PAD is associated with decreased cognitive performance, but the underlying mechanisms remain obscure. Normal brain function critically depends on an adequate adjustment of cerebral blood supply to match the needs of active brain regions via neurovascular coupling (NVC). NVC responses depend on healthy microvascular endothelial function. PAD is associated with significant endothelial dysfunction in peripheral arteries, but its effect on NVC responses has not been investigated. This study was designed to test the hypothesis that NVC and peripheral microvascular endothelial function are impaired in PAD. We enrolled 11 symptomatic patients with PAD and 11 age- and sex-matched controls. Participants were evaluated for cognitive performance using the Cambridge Neuropsychological Test Automated Battery and functional near-infrared spectroscopy to assess NVC responses during the cognitive n-back task. Peripheral microvascular endothelial function was evaluated using laser speckle contrast imaging. We found that cognitive performance was compromised in patients with PAD, evidenced by reduced visual memory, short-term memory, and sustained attention. We found that NVC responses and peripheral microvascular endothelial function were significantly impaired in patients with PAD. A positive correlation was observed between microvascular endothelial function, NVC responses, and cognitive performance in the study participants. Our findings support the concept that microvascular endothelial dysfunction and neurovascular uncoupling contribute to the genesis of cognitive impairment in older PAD patients with claudication. Longitudinal studies are warranted to test whether the targeted improvement of NVC responses can prevent or delay the onset of PAD-associated cognitive decline.NEW & NOTEWORTHY Peripheral artery disease (PAD) was associated with significantly decreased cognitive performance, impaired neurovascular coupling (NVC) responses in the prefrontal cortex (PFC), left and right dorsolateral prefrontal cortices (LDLPFC and RDLPFC), and impaired peripheral microvascular endothelial function. A positive correlation between microvascular endothelial function, NVC responses, and cognitive performance may suggest that PAD-related cognitive decrement is mechanistically linked, at least in part, to generalized microvascular endothelial dysfunction and subsequent impairment of NVC responses.

Baseline Pro-Inflammatory Cytokine Levels Moderate Psychological Inflexibility in Behavioral Treatment for Chronic Pain

Background: The medical and scientific communities struggle to understand chronic pain and find effective treatments. Multimodal approaches are encouraging but show significant individual differences. Methods: Seventy-eight persons (56 women) with chronic pain received Acceptance and Commitment Therapy and provided blood samples before and after treatment. The participants completed surveys with the blood sampling. Blood plasma was analyzed for IL-6 and TNF-α levels with the Olink Inflammation Panel (Olink Bioscience Uppsala, Sweden). The treatment effects and moderating effects of low-grade inflammation on changes in outcomes were analyzed using linear mixed models. Results: Pain interference (p < 0.001) and psychological inflexibility (p < 0.001) improved significantly during treatment, but pain intensity did not (p = 0.078). Cytokine levels did not change over the course of the treatment (IL-6/TNF-α p = 0.086/0.672). Mean baseline levels of IL-6 and TNF-α moderated improvement in psychological inflexibility during the course of treatment (p = 0.044), but cytokine levels did not moderate changes in pain interference (p = 0.205) or pain intensity (p = 0.536). Conclusions: Higher baseline inflammation levels were related to less improvement in psychological inflexibility. Low-grade inflammation may be one factor underlying the variability in behavioral treatment in chronic pain.

Lung function impairment in relation to cognition and vascular brain lesions: the Rotterdam Study

OBJECTIVE

To investigate the association of chronic obstructive pulmonary disease (COPD) and Preserved Ratio Impaired Spirometry (PRISm) with cognitive performance and presence of vascular brain lesions (VBL).

METHODS

We determined both cross-sectional and longitudinal association of lung function impairment with cognition, as well as cross-sectional association of lung function impairment with VBL, in the general population. Between 2009 and 2014 we included 3,941 participants from the Rotterdam Study with spirometry tests, brain MRI scans and cognition tests, of whom 1815 had follow-up data on cognition.

RESULTS

Our finding indicated that cross-sectionally, participants with PRISm or COPD GOLD2-4 had a worse global cognitive performance. We did not find differences in cognition over time between those with normal spirometry versus those with lung function impairment. In addition, PRISm and COPD GOLD2-4 were associated with a higher prevalence of lacunar infarcts compared to normal spirometry.

CONCLUSIONS

This study suggests that persons with COPD GOLD2-4 or restrictive lung function, defined as PRISm, are characterized by poorer global cognitive function and a higher prevalence of lacunar infarcts.

The prothrombotic state in cancer

Neoplasms result from changes in the mechanisms of growth, differentiation, and cellular death. Cancers are of high clinical relevance due to their prevalence and associated morbidity and mortality. The clinical and biological diversity of cancer depends mainly on cellular origin and degree of differentiation. These changes result from alterations in molecular expression that generate a complex clinical, biochemical, and morphologic phenotype. Although cancer is associated with a hypercoagulable state, few cancers result in a thrombotic event. Many factors influence thrombotic incidence, such as advanced disease, central catheter placement, chemotherapy, neoplasia, and surgery. The pro-coagulant state is associated with anomalies in the vascular wall, blood flow, blood constituents (tissue factor, thrombin), coagulation state, and cell growth factors. Tumor cells perpetuate this phenomenon by releasing tissue factor, inflammatory cytokines, and growth factors. These changes favor cellular activation that gives rise to actions involving coagulation, inflammation, thrombosis, tumor growth, angiogenesis, and tumor metastases. These, in turn, are closely linked to treatment response, tumor aggressiveness, and host survival. Activation of the coagulation cascade is related to these phenomena through molecules that interact in these processes. As such, it is necessary to identify these mediators to facilitate treatment and improve outcomes.

Long sleep duration is associated with cognitive frailty among older community-dwelling adults: results from West China Health and Aging Trend study

OBJECTIVE

To investigate the association between sleep duration and cognitive frailty among older adults dwelling in western China.

METHODS

We used the baseline data from West China Health and Aging Trend (WCHAT) study. Sleep duration was classified as short sleep duration (< 6 h), normal sleep duration (6-8 h) and long sleep duration (≥ 9 h). Fried frailty criteria and Short Portable Mental Status Questionnaire were used to measure cognitive frailty. Multinomial logistic regression was conducted to estimate odds ratio (OR) and 95% confidence interval (CI).

RESULTS

A total of 4093 older adults (age = 67.8 ± 5.9 years, 1708 males and 2385 females) were included in the analysis. The prevalence of cognitive frailty was 11.8% among older adults in western China. Approximately 11.9% participants had short sleep duration (< 6 h); 22.2% had a long sleep duration (≥ 9 h). After adjusting for covariates, only long sleep duration was significantly associated with high risk of cognitive frailty (OR = 2.07, 95%CI = 1.60-2.68, P <  0.001) in western China older adults compared to normal sleep duration.

CONCLUSIONS

Long sleep duration was significantly related to cognitive frailty in older adults. Intervention for long sleep duration may be helpful to prevent cognitive frailty.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR1800018895 .

Cognitive decrement in older adults with symptomatic peripheral artery disease

Peripheral artery disease (PAD) is highly prevalent, affecting up to 20% of people over 70 years of age. To test the hypothesis that PAD promotes the pathogenesis of vascular cognitive impairment (VCI), we compared cognitive function in older adults with symptomatic PAD and in participants without PAD who had a burden of comorbid conditions. Furthermore, we compared the cognitive function of these groups after adjusting for demographic and clinical characteristics, comorbid conditions, and cardiovascular risk factors. Participants with PAD (age: 69 ± 8 years; n = 58) and those without PAD (age: 62 ± 8 years; n = 30) were assessed on a battery of eight neuropsychological tests. The tests assessed attention and working memory, verbal memory, non-verbal memory, perceptuo-motor speed, and executive function. Participants were further characterized on demographic and clinical characteristics, comorbid conditions, cardiovascular risk factors, and ankle-brachial index. The PAD group had significantly lower neuropsychological scores than the non-PAD control group on all eight tests (P < .01). After adjusting for covariates, significantly worse scores in the PAD group persisted for verbal memory, measured by tests on logical memory-immediate recall (P = .022), and logical memory-delayed recall (P < .001), and for attention and working memory, measured by tests on digits forward (P < .001), and digits backward (P = .003). Participants with symptomatic PAD have substantially lower levels of performance on tests of attention, working memory, and verbal memory than participants without PAD independent of demographic characteristics and comorbid health burdens. These findings provide additional evidence in support of the concept that generalized accelerated vascular aging manifesting as symptomatic PAD in the peripheral circulation also affects the brain promoting the pathogenesis of VCI. These cognitive difficulties may also negatively impact symptomatic patient's ability to understand and adhere to behavioral and medical therapies, creating a vicious cycle. We speculate that more intensive follow-up may be needed to promote adherence to therapies and monitor cognitive decline that may affect care.

Potentially undiagnosed cognitive impairment in patients with peripheral arterial disease: A systematic review of the literature

INTRODUCTION

It is purported that patients with peripheral arterial disease (PAD) may have impaired cognitive function due to concomitant cerebrovascular disease. Such disease may be clinically unrecognized but can impact on a patient's recovery and prognosis. The purpose of this systematic review was to interrogate the body of published evidence on undiagnosed cognitive impairment in PAD patients.

METHODS

A search strategy encompassing MEDLINE, Scopus, and the Cochrane database was developed to identify peer-reviewed articles examining rates of undiagnosed cognitive impairment in patients with PAD. The following search terms were used: 'PAD'; 'PVD'; 'dementia'; 'peripheral arterial disease'; 'peripheral vascular disease'; 'cognitive impairment'; 'alzheimer's disease' and 'cogniti∗'. Our primary outcome was the incidence of previously undiagnosed cognitive impairment in patients with PAD.

RESULTS

The initial search yielded 1492 titles. After removal of duplicates, 961 abstracts were screened to ascertain if they were eligible for inclusion. Abstract review yielded 62 full texts for further evaluation. Eight case-control studies consisting of 1161 patients were included. Analysis of these studies revealed that PAD patients performed significantly worse than controls on a variety of neuropsychological measures.

CONCLUSION

Our review indicated that PAD patients are more likely to suffer with undiagnosed cognitive impairment than healthy controls.

Correlation between Serum Platelet Count and Cognitive Function in Patients with Atrial Fibrillation: A Cross-Sectional Study

BACKGROUND

The risk of cognitive impairment in patients with atrial fibrillation is significantly increased. Its occurrence may be related to blood hypercoagulable state and immune inflammatory reaction. Platelets can mediate immune inflammatory response, but there is no evidence about the relationship between platelet count and cognitive function in patients with atrial fibrillation.

PURPOSE

To explore whether there is a certain correlation between platelet count and cognitive function in patients with atrial fibrillation.

METHODS

A cross-sectional study was conducted in a single center in China, including 254 patients with atrial fibrillation. Cognitive function assessment and clinical and laboratory examinations were performed on all participants. After adjusting the related confounding factors, the relationship between platelet count and cognitive function was analyzed.

RESULTS

A total of 254 subjects with an average age of 59.71 ± 11.14 years were included. The average platelet count was 208.15 ± 68.30, and the average score of cognitive function was 19.29 ± 6.78. Result of fully adjusted binary logistic regression showed platelet count was negatively associated with the cognitive function score after adjusting confounders (hazard ratio (HR) = 0.000, 95%CI -0.01, 0.01). A nonlinear relationship was detected between platelet count and the cognitive function score, whose point was 230. The effect sizes and the confidence intervals of the left and right sides of the inflection point were 0.03 (0.01-0.05, P for nonlinearity = 0.011) and -0.03 (-0.05-0.00, P for nonlinearity = 0.023), respectively.

CONCLUSION

Platelets have a nonlinear relationship with cognitive function in patients with atrial fibrillation. This finding suggests that, in patients with atrial fibrillation, platelets should be maintained at about 230.

Purinergic signaling in nervous system health and disease: Focus on pannexin 1

Purinergic signaling encompasses the cycle of adenosine 5' triphosphate (ATP) release and its metabolism into nucleotide and nucleoside derivatives, the direct release of nucleosides, and subsequent receptor-triggered downstream intracellular pathways. Since the discovery of nerve terminal and glial ATP release into the neuropil, purinergic signaling has been implicated in the modulation of nervous system development, function, and disease. In this review, we detail our current understanding of the roles of the pannexin 1 (PANX1) ATP-release channel in neuronal development and plasticity, glial signaling, and neuron-glial-immune interactions. We additionally provide an overview of PANX1 structure, activation, and permeability to orientate readers and highlight recent research developments. We identify areas of convergence between PANX1 and purinergic receptor actions. Additional highlights include data on PANX1's participation in the pathophysiology of nervous system developmental, degenerative, and inflammatory disorders. Our aim in combining this knowledge is to facilitate the movement of our current understanding of PANX1 in the context of other nervous system purinergic signaling mechanisms one step closer to clinical translation.

The association between systemic inflammation and cognitive performance in healthy adults

BACKGROUND

Several studies have indicated that mild systemic inflammation is associated with the risk of cognitive impairment. However, not every cognitive domain has been evaluated to have a correlation with peripheral inflammation in healthy individuals. Therefore, we aimed to investigate the association between C-reactive protein (CRP) as a marker of peripheral inflammation with various domains of cognition in healthy adults.

METHOD

This study consisted of 216 healthy native German adults (138 males and 78 females, mean age: 39.12 ± 20.19 years) from "Leipzig Study for Mind-Body-Emotion Interactions" (LEMON) database. After the initial assessment and conducting the cognitive battery, a blood sample was collected and CRP level was evaluated. Patients were categorized into three groups based on their CRP level. Subsequently, demographic and cognitive features were compared across three groups and to confirm the association between CRP level and cognitive performance, general linear models (GLM) were applied.

RESULTS

All California Verbal Learning Task (CVLT)-evaluated aspects of memory performance were inversely associated with CRP level, some of which remained significant after the adjustment for age, gender, education, smoking status and body mass index. Moreover, GLM analysis indicated that mean reaction time of the Test of Attentional Performance-Alertness (TAP-A) test (with and without signal) was also significantly associated with CRP level.

CONCLUSION

The current study indicated that healthy subjects with higher levels of CRP exhibit poorer performance in verbal learning memory and general wakefulness domains of cognition.

Beneficial Effect of Exercise on Cognitive Function during Peripheral Arterial Disease: Potential Involvement of Myokines and Microglial Anti-Inflammatory Phenotype Enhancement

Peripheral arterial disease (PAD), leading to intermittent claudication, critical ischemia with rest pain, and/or tissue damage, is a public health issue associated with significant morbidity and mortality. Little is known about the link between PAD, cognitive function, and whether exercise might reduce cognitive dysfunction in PAD patients, as previously observed concerning both quality of life and prognosis. This review highlights the fact that patients suffering from PAD often demonstrate cognitive dysfunction characterized by reduced performance in nonverbal reasoning, reduced verbal fluency, and decreased information processing speed and a greater risk for progression toward dementia. Further, the data presented support that physical exercise, likely through myokine secretion and microglial anti-inflammatory phenotype enhancement, might participate in the cognition protection in common clinical settings.

Systemic Inflammation Is Associated With Longitudinal Changes in Cognitive Performance Among Urban Adults

Objectives/Background: Systemic inflammation can affect cognitive performance over time. The current study examined associations between systemic inflammation and cognitive performance among African Americans and Whites urban adults, stratifying by sex, and age group and by race. Patients/Methods: Among 1,555-1,719 White and African-American urban adults [Age_base: 30-64y, 2004-2013, mean±SD follow-up time(y): 4.64 ± 0.93y], conducted linear mixed-effects regression models were conducted to test associations of inflammatory markers [C-reactive protein, Erythrocyte Sedimentation Rate (ESR), albumin, iron, and an inflammation composite score (ICS)] with longitudinal cognitive performance. Results: Among key findings, CRP was linked to poorer baseline mental status among younger women (≤50y, γ₀₁ = -0.03 ± 0.01, p = 0.002) and poorer attention in older women (>50y, γ₀₁ = -0.024 ± 0.007, p < 0.004) and African-Americans (γ₀₁ = -0.029 ± 0.008, p < 0.001). ESR was related to faster decline on verbal memory among older men (>50y, γ₁₁ = -0.008 ± 0.003, P = 0.009); with poorer performance on attention tests overall (γ₀₁ = -0.010 ± 0.003, P = 0.003) and among African-Americans (γ₀₁ = -0.013 ± 0.004, P = 0.002); on verbal fluency among older women (>50y,γ₀₁ = -0.037 ± 0.013, P = 0.004) and on executive function: overall (γ₀₁ = +0.62 ± 0.21, P = 0.004), older men (>50y, γ₀₁ = +1.69 ± 0.53, P = 0.001) and African-Americans (γ₀₁ = +0.84 ± 0.28, P = 0.002). Albumin was linked to slower attention decline among older men (>50y, γ₁₁ = +0.329 ± 0.103, P = 0.009), over-time improvement in executive function overall (γ₁₁ = -6.00 ± 2.26, P = 0.008), and better baseline psychomotor speed among African-Americans (γ₀₁ = +0.56 ± 0.19, P = 0.003). Finally, ICS predicted faster decline on visual memory/visuo-constructive abilities among older men (>50y, γ₁₁ = +0.17 ± 0.06, p = 0.003). Conclusion: In sum, strong associations between systemic inflammation and longitudinal cognitive performance were detected, largely among older individuals (>50y) and African-Americans. Randomized trials targeting inflammation are warranted.

High-sensitivity C-reactive protein and cognitive decline: the English Longitudinal Study of Ageing

BACKGROUND

High-sensitivity C-reactive protein (hs-CRP) has been suggested to be involved in the process of cognitive decline. However, the results from previous studies exploring the relationship between hs-CRP concentration and cognitive decline are inconsistent.

METHOD

We employed data from wave 2 (2004-2005) to wave 7 (2014-2015) of the English Longitudinal Study of Ageing. Cognitive function was assessed at baseline (wave 2) and reassessed biennially at waves 3-7.

RESULTS

A total of 5257 participants (54.9% women, mean age 65.4 ± 9.4 years) with baseline hs-CRP levels ranged from 0.2 to 210.0 mg/L (median: 2.0 mg/L, interquartile range: 0.9-4.1 mg/L) were studied. The mean follow-up duration was 8.1 ± 2.8 years, and the mean number of cognitive assessment was 4.9 ± 1.5. Linear mixed models show that a one-unit increment in natural log-transformed hs-CRP was associated with faster declines in global cognitive scores [-0.048 points/year, 95% confidence interval (CI) -0.072 to -0.023], memory scores (-0.022 points/year, 95% CI -0.031 to -0.013), and executive function scores (-0.025 points/year, 95% CI -0.043 to -0.006), after multivariable adjustment. Compared with the lowest quartile of hs-CRP, the multivariable-adjusted rate of global cognitive decline associated with the second, third, and highest quartile was faster by -0.043 points/year (95% CI -0.116 to 0.029), -0.090 points/year (95% CI -0.166 to -0.015), -0.145 (95% CI -0.221 to -0.069), respectively (p for trend <0.001). Similarly, memory and executive function also declined faster with increasing quartiles of hs-CRP.

CONCLUSIONS

A significant association between hs-CRP concentration and long-term cognitive decline was observed in this study. Hs-CRP might serve as a biomarker for cognitive decline.

Vascular disease in cocaine addiction

Cocaine, a powerful vasoconstrictor, induces immune responses including cytokine elevations. Chronic cocaine use is associated with functional brain impairments potentially mediated by vascular pathology. Although the Crack-Cocaine epidemic has declined, its vascular consequences are increasingly becoming evident among individuals with cocaine use disorder of that period, now aging. Paradoxically, during the period when prevention efforts could make a difference, this population receives psychosocial treatment at best. We review major postmortem and in vitro studies documenting cocaine-induced vascular toxicity. PubMed and Academic Search Complete were used with relevant terms. Findings consist of the major mechanisms of cocaine-induced vasoconstriction, endothelial dysfunction, and accelerated atherosclerosis, emphasizing acute, chronic, and secondary effects of cocaine. The etiology underlying cocaine's acute and chronic vascular effects is multifactorial, spanning hypertension, impaired homeostasis and platelet function, thrombosis, thromboembolism, and alterations in blood flow. Early detection of vascular disease in cocaine addiction by multimodality imaging is discussed. Treatment may be similar to indications in patients with traditional risk-factors, with few exceptions such as enhanced supportive care and use of benzodiazepines and phentolamine for sedation, and avoiding β-blockers. Given the vascular toxicity cocaine induces, further compounded by smoking and alcohol comorbidity, and interacting with aging of the crack generation, there is a public health imperative to identify pre-symptomatic markers of vascular impairments in cocaine addiction and employ preventive treatment to reduce silent disease progression.

Low-grade inflammation is a major contributor of impaired attentional set shifting in obese subjects

Impairment in cognitive flexibility and set shifting abilities has been described in obesity. This alteration is critical as it can interfere with obesity management strategies. Recent evidences suggest that chronic low-grade inflammation may be involved in cognitive deficits associated with obesity, but the potential involvement in reduced flexibility remains unknown. The objective of this study was to assess the contribution of low-grade inflammation, determined by circulating levels of high-sensitivity C-reactive protein (hsCRP), in reduced cognitive flexibility and shifting abilities of obese subjects relatively to a group of non-obese participants. Performance in the intra/extra-dimensional set shift (IED) test, extracted from the CANTAB, was assessed in 66 obese subjects and 20 non-obese participants. Obese subjects with concentrations of hsCRP above 5mg/L exhibited reduced performance on the IED test in comparison to obese subjects with lower levels of hsCRP and non-obese participants. This difference was particularly manifest in the number of errors made during the extra-dimensional shift (EDS errors). In contrast, performance before the extra-dimensional shift was spared. Linear regression analyses revealed that the association between obesity and IED alterations was significant only when the condition hsCRP >5mg/L was entered in the model. These findings are important as they indicate that, rather than obesity itself, low-grade inflammation represents a major contributor of IED performance in obese subjects.

Chronic Peripheral Inflammation is Associated With Cognitive Impairment in Schizophrenia: Results From the Multicentric FACE-SZ Dataset

OBJECTIVES

Inflammation, measured by abnormal blood C-reactive protein (CRP) level, has been described in schizophrenia (SZ), being inconsistently related to impaired cognitive functions. The aim of the present study is to investigate cognitive impairment associated with abnormal CRP levels in a large multi-centric sample of community-dwelling SZ patients, using a comprehensive neuropsychological battery.

METHOD

Three hundred sixty-nine community-dwelling stable SZ subjects (76.2% men, mean age 32.7 y) were included and tested with a comprehensive battery of neuropsychological tests. Abnormal CRP level was defined as >3mg/L.

RESULTS

Multiple factor analysis revealed that abnormal CRP levels, found in 104 patients (28.2%), were associated with impaired General Intellectual Ability and Abstract Reasoning (aOR = 0.56, 95% CI 0.35-0.90, P = .014), independently of age, sex, education level, psychotic symptomatology, treatments, and addiction comorbidities. Abnormal CRP levels were also associated with the decline of all components of working memory (respectively effect size [ES] = 0.25, P = .033; ES = 0.27, P = .04; ES = 0.33, P = .006; and ES = 0.38, P = .004) and a wide range of other impaired cognitive functions, including memory (ES = 0.26, P = .026), learning abilities (ES = 0.28, P = .035), semantic memory (ES = 0.26, P = .026), mental flexibility (ES = 0.26, P = .044), visual attention (ES = 0.23, P = .004) and speed of processing (ES = 0.23, P = .043).

CONCLUSION

Our results suggest that abnormal CRP level is associated with cognitive impairment in SZ. Evaluating the effectiveness of neuroprotective anti-inflammatory strategies is needed in order to prevent cognitive impairment in SZ.

Executive Dysfunction Following Critical Illness: Exploring Risk Factors and Management Options in Geriatric Populations

Cognitive impairment is a common occurrence that has been shown to occur in over 50 % of patients following critical illness. This impairment occurs across a range of domains including attention, memory, processing speed, and executive dysfunction. In this article, we will discuss the pathophysiology behind cognitive impairment including hypoxemia and cytokines. Secondly, we will describe the risk factors for cognitive impairment including age, length of stay, and delirium. Lastly, we will review emerging data related to the use of cognitive rehabilitation, formation of postintensive care clinics in qualifying patients, and potential neuropharmacologic therapy. While our chapter focuses on cognitive impairment generally, it places a particular emphasis on executive dysfunction, not because impairment occurs solely in this domain but because impairments of an executive nature may be uniquely debilitating.

Effect of cognitive status on exercise performance and quality of life in patients with symptomatic peripheral artery disease

BACKGROUND

We determined whether scores on a cognitive screening measure were associated with the primary outcome measure of peak walking time (PWT) and with secondary outcome measures related to mobility, community-based ambulation, health-related quality of life (QoL), and vascular function in patients with claudication and peripheral artery disease (PAD).

METHODS

Gross cognitive status of 246 PAD patients was assessed with the Mini-Mental State Examination (MMSE) questionnaire. Patients were grouped according to whether they had a perfect MMSE score of 30 points (n = 123) or whether they missed one or more points (n = 123). Patients were characterized on numerous outcomes, including PWT during a treadmill test and QoL.

RESULTS

Compared with the group with the higher MMSE scores, there was a trend for lower PWT in the group with the lower MMSE scores (P = .06) after adjusting for age, sex, race, and education level (model 1), which became significant (380 ± 250 seconds vs 460 ± 270 seconds; P < .05) after adjusting for model 1 plus coronary artery disease, chronic obstructive pulmonary disease, and arthritis (model 2). Multiple domains of QoL were lower (P < .05) in the group with the lower MMSE scores after adjusting for model 1, but only mental health remained lower (75 ± 20% vs 80 ± 5%; P = .02) after further adjustment with model 2.

CONCLUSIONS

In symptomatic patients with PAD, lower cognitive screening scores were associated with greater ambulatory impairment than in patients with higher MMSE scores. Furthermore, worse cognitive status was associated with lower scores in multiple dimensions of health-related QoL, all of which except mental health were explained by the comorbid conditions of coronary artery disease, chronic obstructive pulmonary disease, and arthritis. The clinical significance is that there is a need for enhanced cognitive and mental health screening as potential indicators of poor outcome among symptomatic patients with PAD. Furthermore, patients identified as having worse cognitive status might be in greatest need of intervention to improve ambulation and QoL related to mental health.

Association between functional performance and executive cognitive functions in an elderly population including patients with low ankle-brachial index

Introduction

Peripheral arterial disease, as measured by the ankle–brachial index (ABI), is prevalent among the elderly, and is associated with functional performance, assessed by the 6-minute walk test (6MWT). Executive cognitive function (ECF) impairments are also prevalent in this population, but no existing study has investigated the association between ECF and functional performance in an elderly population including individuals with low ABI.

Aim

To investigate the association between functional performance, as measured by the 6MWT, and loss in ECF, in an elderly sample including individuals with low ABI.

Method

The ABI group was formed by 26 elderly individuals with low ABI (mean ABI: 0.63±0.19), and the control group was formed by 40 elderly individuals with normal ABI (mean ABI: 1.08±0.07). We analyzed functional performance using the 6MWT, global cognition using the Mini-Mental State Examination (MMSE), and ECF using the Digit Span for assessing attention span and working memory, the Stroop Color Word Test (SCWT) for assessing information processing speed and inhibitory control/impulsivity, and the Controlled Oral Word Association Test (COWAT) for assessing semantic verbal fluency and phonemic verbal fluency. We also used a factor analysis on all of the ECF tests (global ECF).

Results

Before adjustment, the ABI group performed worse on global cognition, attention span, working memory, inhibitory control/impulsivity, semantic verbal fluency, and phonemic verbal fluency. After adjustment, the ABI group performance remained worse for working memory and semantic verbal fluency. In a simple correlation analysis including all of the subjects, the 6MWT was associated with global cognition, attention span, working memory, information processing speed, inhibitory control/impulsivity, semantic verbal fluency, and global ECF. After adjustment, all the associations remained statistically significant.

Conclusion

This study found an independent association between functional performance and ECF in an elderly population including low ABI individuals, showing that, in elderly populations with functional impairment, ECF may also be impaired.

C-reactive protein plays a marginal role in cognitive decline: a systematic review and meta-analysis

OBJECTIVE

The objective of the study was to investigate the association between peripheral levels of C-reactive protein (CRP) and cognitive decline that is defined by 2-5 years of cognitive change in general cognitive function or specific cognitive domain.

METHODS

We searched PubMed and Google for prospective/longitudinal studies that report the association between peripheral levels of CRP and risk of cognitive decline in the nondementia population.

RESULTS

Out of 479 related articles from PubMed and Google, four studies with a total of 5255 non-demented subjects that report odds ratio (OR)/relative risk/hazard ratio of CRP levels and decline in general cognition met our criteria for meta-analysis. The association between higher levels of CRP and risk of global cognitive decline was weak but significant (OR, 1.27 [95% CI, 1.02 to 1.58]). However, the systematic review from six other articles that were not suitable for meta-analysis revealed a marginal association between CRP and cognitive decline in certain domains.

CONCLUSION

Our analysis demonstrated a weak association between peripheral CRP level and global cognitive decline. Because of the small number of included studies and varied methodologies that they applied, caution should be taken when generalizing our finding to the full range of cognitive changes in different cognitive domains observed in non-demented people.

The association between depressive symptoms, cognitive function, and inflammation in major depression

The purpose of this study was to assess the association between IL-6 and CRP with depressive items and cognitive function. We included 112 outpatients with major depression from an exercise trial and 57 healthy controls. IL-6, high sensitive CRP (hsCRP), and cognitive function were assessed in all subjects. After baseline assessment, patients were randomised to either a 3months exercise intervention or an exercise control group. Post-intervention IL-6, hsCRP, depressive symptoms, and cognitive function were reassessed in the patient group. IL-6 and hsCRP were significantly increased in depressed patients compared to healthy controls (p=0.02 and 0.04). These differences were no longer significant after adjustment for lifestyle associated variables. We found no association between immune markers and specific depressive symptoms at baseline or as change over time. Regarding the cognitive tests, IL-6 was positively associated with Serial sevens (p=0.008) and hsCRP was inversely associated with Trail making A (p=0.02) and design fluency (p=0.001) at baseline. At 3months follow-up IL-6 and hsCRP levels did not significantly change from baseline and did not differ between the two patient groups. Depression scores was lower compared to baseline but did not differ between groups. Combining the two groups, a decrease in IL-6 was associated to decreased verbal fluency (p=0.02), and a decrease in hsCRP was associated with improvement in Trail making A (p=0.005). In conclusion, the level of IL-6 and hsCRP was increased in depressed outpatients but was not associated to specific depressive symptoms. In terms of cognitive function, we found that higher hsCRP levels were associated to lower psychomotor speed both at baseline and at follow-up.

A Study of Association of Ankle Brachial Index (ABI) and the Highly Sensitive C - Reactive Protein (hsCRP) in Type 2 Diabetic Patients and in Normal Subjects

BACKGROUND

The Ankle-Brachial Index (ABI) objectively assesses the lower extremity arterial perfusion. A low ABI suggests atherosclerosis and Peripheral Arterial Disease (PAD). PAD is more common in individuals with type2 Diabetes mellitus (Type2 DM). Inflammatory markers are found to be associated with Type2 DM. But the association of the inflammatory markers with the atherosclerotic burden remains poorly defined.

AIMS

To compare the ABI and the hsCRP in the Type 2 DM patients with those in the normal subjects and to study the association of serum hsCRP with ABI in the Type 2 DM patients and in normal subjects.

METHODS

The subjects were 40 Type2 DM and 40 age, sex and BMI matched normal subjects who were aged between 45-60 yrs. The subjects were assigned to two different groups, Group1- the Type2 DM patients and Group2- the healthy controls. The serum hsCRP levels were determined by the turbidimetry method (BIOSYSTEMS) and the ABI values were determined by using the traditional continuous wave (CW) Doppler of NICOLET VERSALAB.

STATISTICAL ANALYSIS

The data was analyzed by using the Student's t test (two tailed; independent) to find the significance of the study parameters between the two groups. Pearson's Correlation was used to find the correlation of serum hsCRP with the ABI in the two groups.

RESULTS

The ABI showed a significantly low value (P=0.035*) and the serum hsCRP showed a trend towards a significant increase (p = 0.069+) in the type2diabetics as compared to those in the normals. There was a significant negative correlation between ABI and hsCRP in the Type 2 DM patients (r=-0.560, p<0.001**). However, such correlation was not observed in the normal subjects.

CONCLUSION

As serum hsCRP is associated with ABI in the type2 DM patients, inflammation may play a role in the pathogenesis of atherosclerosis.

The relation between atherosclerosis and the occurrence of postoperative delirium in vascular surgery patients

Old and frail patients undergoing vascular surgery seem at great risk of developing postoperative delirium (POD). The aim of this review was to identify risk factors for the development of POD in vascular surgery patients. Different aetiological factors have been identified, such as increased age, excessive blood transfusion, preoperative cognitive impairment and depression. Mounting evidence supports a role for inflammation and tobacco exposure in the development of POD. Vascular surgery patients differ from the general surgical population because they suffer from both loco-regional and systemic atherosclerosis. Although current scientific evidence cannot fully link both entities, evidence is growing that suggests a relationship between systemic and cerebrovascular atherosclerosis and the development of POD.

Nitric oxide plasma concentration associated with cognitive impairment in patients with recurrent depressive disorder

BACKGROUND/AIM

Depressive disorders are multifactorial diseases, in which cognitive impairment is one of the characteristic feature. One of the molecules that regulate of various cognitive, emotional and behavioural processes is nitric oxide (NO), synthesized from l-arginine by a family of isoformic enzymes known as nitric oxide synthases (NOS). NO is a gaseous compounds that acts as a biological second messenger in a number of organ system. In addition, NO is a ubiquitous free radical (NO) that affects many normal physiologic functions but is also implicated in the etiology and progression of many diseases. The aim of the study was to determine the concentration of NO in patients with recurrent depressive disorder (rDD) and to define relationship between plasma NO levels and the cognitive performance.

METHODS

The study comprised 78 subjects: patients with rDD (n=45), healthy controls (CG, n=33). Cognitive function assessment was based on: TMT, The Stroop Test, VFT, AVLT.

RESULTS

Statistically significant differences were found among patients with rDD in the intensity of depression symptoms, measured by the HDRS on therapy onset vs. the examination results after 8 weeks of treatment (p<0.001). The level of NO was substantially higher in patients with rDD compared to CG. For all examined subjects (p<0.001), elevated levels of NO in blood plasma adversely affect the efficiency of visual-spatial and auditory-verbal working memory as well as short-term declarative memory. For rDD patients, elevated NO levels were associated with worse cognitive test performance. The higher was the concentration of plasma NO, the greater was the severity of depressive symptoms measured by HDRS (p=0.03).

CONCLUSIONS

(1) Higher concentration of plasma NO in rDD patients is associated with the severity of depressive symptoms. (2) Elevated levels of plasma NO are related to impairment of visual-spatial and auditory-verbal working memory as well as to impairment of short-term declarative memory.

Association between circulating hemostatic measures and dementia or cognitive impairment: systematic review and meta-analyzes

BACKGROUND AND OBJECTIVES

Hemostasis and thrombosis may be important contributors to cognitive decline and dementia. Certain blood markers may assist in diagnosis or management.

OBJECTIVES

To collate evidence for the association of circulating hemostatic variables and dementia or cognitive impairment.

METHODS

A systematic review of studies describing blood markers of hemostatic function and cognition/dementia. Abstracts were reviewed by two independent assessors and studies selected based on pre-specified criteria. We described methodological quality and performed meta-analyzes where data allowed.

RESULTS

From 7103 titles, 485 abstracts and included 21 studies (n = 32,773) were assessed. In two longitudinal studies, the incident of vascular dementia risk was greater for higher D-dimer [hazard ratio (HR): 1.50, 95% confidence interval (CI): 1.15-1.96]. For case-control data, we calculated standardized mean differences (SMD) and 95% CI. Higher levels of: factor (F)VII (SMD: 0.93; 95% CI: 0.60-1.26), fibrinogen (SMD: 1.53; 95% CI: 1.17-1.87), prothrombin fragment 1 and 2 (SMD: 0.64; 95% CI: 0.32-0.96), plasminogen activator inhibitor (SMD: 0.68; 95% CI: 0.26-1.10), D-dimer (SMD: 2.00; 95% CI: 1.59-2.40) and von Willebrand factor (VWF) (SMD: 1.68; 95% CI: 1.30-2.06) showed modest but significant associations with vascular dementia. For patients with any dementia diagnosis, associations were with higher D-dimer (SMD: 0.36; 95% CI: 0.15-0.56) and VWF (SMD: 0.31; 95% CI: 0.11-0.51). For specific cognitive domains, significant (P < 0.001) positive correlations were fibrinogen and speed of processing (0.76; 95% CI: 0.67-0.84), verbal memory (0.69; 95% CI: 0.59-0.79) and non-verbal reasoning (0.57; 95% CI: 0.49-0.65).

CONCLUSIONS

The present results suggest a modest association between hemostasis and vascular dementia including increased levels of thrombin generation markers (D-dimer and prothrombin fragment 1 + 2) and endothelial dysfunction (VWF and plasminogen activator inhibitor). Associations are weaker for specific cognitive tests and when all dementias are combined.

The relationship between inflammatory markers and post stroke cognitive impairment

OBJECTIVE

To determine whether there is a relationship between inflammatory markers (serum C-reactive protein (CRP) and cytokines) and post stroke cognitive impairment (PSCI).

METHODS

This was a cross-sectional observational study. Patients were recruited from 4 sources: (1) the acute stroke unit of a general hospital, (2) an outpatient stroke prevention clinic, (3) a stroke rehabilitation unit in a specialized geriatric hospital, or (4) a stroke rehabilitation unit of a rehabilitation hospital. Patients meeting National Institute of Neurological and Communicative Disorders and Stroke (NINCDS) and World Health Organization Multinational Monitoring of Trends and Determinants in Cardiovascular Disease (WHO-MONICA) project criteria for stroke were invited to participate in this study within the first 5 to 31 days post stroke. Patients with subarachnoid or intracranial hemorrhage, decreased level of consciousness, severe aphasia or dysarthria, or a significant acute medical, neurological, or psychiatric illness were excluded. Clinical assessments included the Mini-Mental State Examination (MMSE) for cognition, the National Institutes of Health Stroke Scale (NIHSS) for stroke severity, and the Center for Epidemiological Studies-Depression Scale (CES-D) for depressive symptoms. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum concentrations of CRP, interleukin 6 (IL-6), and interferon gamma (IFN-gamma).

RESULTS

A total of 48 patients with ischemic stroke (age [mean +/- SD] 71.6 +/- 13.2 years, 54.2% male, MMSE 26.4 +/- 3.8, NIHSS 6.8 +/- 4.0) were recruited within their first month post stroke. Backward stepwise elimination linear regression showed that higher concentrations of serum CRP (beta(CRP) = -0.46, p( CRP) = 0.002) predicted lower post stroke global cognition ([MMSE], F1,44 = 11.31, P = .002), with age (P = .92), level of education (P = .22), infarct side (P = 0.49), IL-6 (P = 0.36), and IFN-gamma (P = .57) removed from the final model.

CONCLUSIONS

A post stroke inflammatory response may be important in subacute, PSCI.

Problem behavior of dementia patients predicts low-grade hypercoagulability in spousal caregivers

BACKGROUND

Low-grade hypercoagulability might be one pathway to explain how the chronic stress of dementia caregiving increases cardiovascular disease risk, but the specific aspects of caregiver stress that elicit hypercoagulability are elusive. We hypothesized that dementia patients' problem behaviors and negative reactions of caregivers to these behaviors would relate to hypercoagulability in caregivers.

METHODS

One hundred and eight participants (mean age 74 +/- 8 years, 70% women) providing in-home care for their spouse with Alzheimer's disease were examined. Caregivers were interviewed about the number of 24 predefined patient problem behaviors in the previous week (range 0-24) and how upset or bothered they felt in response to these behaviors (total score 0-96). Von Willebrand factor, plasminogen activator inhibitor-1, and D-dimer were determined in plasma and standardized z-scores of their concentrations summed into a procoagulant index.

RESULTS

Greater number of problem behaviors (Delta R(2) = 0.046, p = .014) and negative reactions of caregivers to these behaviors (Delta R(2) = 0.044, p = .017) were associated with greater procoagulant index after controlling for sociodemographic factors, major cardiovascular risk factors, health habits, and health problems. However, the number of and reaction to problem behaviors did not significantly predict procoagulant activity independent from each other. Post hoc analysis revealed a positive association between the number of problem behaviors and D-dimer (p = .010, Delta R(2) = 0.053), even when controlling for negative reactions (p = .033, Delta R(2) = 0.036). Caregiver reaction to problem behaviors was not significantly associated with any procoagulant factor individually.

CONCLUSION

Alzheimer patients' problem behavior and their negative appraisal by the caregiver may contribute to the chronic low-grade hypercoagulable state in dementia caregivers.

Brain involvement in rheumatoid arthritis: a magnetic resonance spectroscopy study

OBJECTIVE

Tumor necrosis factor alpha was recently implicated as an important mediator of communication between the peripheral and cerebral immune systems in an animal model of chronic inflammation. The purpose of this study was to examine by proton magnetic resonance spectroscopy ((1)H-MRS) the influence of inflammation on cerebral metabolism in patients with rheumatoid arthritis (RA).

METHODS

Single-voxel (1)H-MRS of the centrum semiovale was performed on 35 RA patients (6 men and 29 women; mean +/- SD age 51.8 +/- 14.6 years) and 28 healthy age- and sex-matched control subjects (9 men and 19 women; mean +/- SD age 50.2 +/- 10.4 years). None of the study subjects had any neurologic signs or symptoms. Clinical markers of disease activity were correlated with the (1)H-MRS findings.

RESULTS

Patients with active RA, as reflected by an elevated erythrocyte sedimentation rate (ESR), had a significantly higher ratio of choline to creatine and a significantly lower ratio of N-acetylaspartate to choline than did patients with inactive RA, as reflected by a normal ESR. Moreover, the ratios of choline to creatine and NAA to choline were significantly correlated with the ESR after correction for age, sex, smoking status, handedness, alcohol consumption, medication use, and disease duration. Medication use had no additional effect on these associations.

CONCLUSION

Our data show that systemic inflammation in RA is associated with metabolic changes in the brain.

Inflammation in aging part 1: physiology and immunological mechanisms

During the aging process, remodeling of several body systems occurs, and these changes can have a startling effect upon the immune system. The reduction in sex steroids and growth hormones and declines in vitamin D concentration that accompany the aging process are associated with increases in the baseline levels of inflammatory proteins. At the same time, inflammation arising from atherosclerosis and other chronic diseases further contributes to the inflammatory milieu and effects a state of chronic inflammation. This chronic inflammation, or ''inflammaging'' as it has been termed, seems to be associated with a host of adverse effects contributing to many of the health problems that increase morbidity and decrease both quality of life and the ability to maintain independence in old age. For nurses to be truly informed when caring for older people and to ensure that they have a detailed understanding of the complexities of older people's health needs, they must have a knowledge of the physiological and immunological changes with age. This is the first of a two-part article on inflammatory processes in aging. These age-related changes are presented here, including an examination of the impact of genetic and lifestyle factors. The effect of these changes on the health of the individual and implications for practice are described in Part 2.

Memory deficits and neurochemical changes induced by C-reactive protein in rats: implication in Alzheimer's disease

RATIONALE

C-reactive protein (CRP), an acute phase protein that is released in response to inflammatory stimuli, is implicated in Alzheimer's disease (AD). However, the role of CRP in memory deficits associated with AD remains unclear.

OBJECTIVE

Experiments were carried out to determine whether CRP impaired memory and altered neurochemical measures associated with AD.

METHODS

The effects of intra-cerebroventricular administration of CRP or beta-amyloid peptide 25-35 (Abeta(25-35)) on memory performance were evaluated using rat Morris water-maze and step-through passive avoidance tests; the levels of inflammatory cytokines (interleukin-1beta (IL-1beta), IL-6, and tumor necrosis factor (TNF-alpha)), endogenous CRP, and markers of the endogenous production of Abeta, including amyloid precursor protein (APP), presenilins (PS-1 and PS-2), and beta-site of APP cleaving enzyme (BACE), were also determined in brain regions using real-time reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting analysis.

RESULTS

Treatment with CRP (25.6 microg/rat) or Abeta(25-35) (10 microg/rat) 2 weeks ahead produced impairment of long-term memory in both animal tests. Real-time RT-PCR revealed increases in messenger RNA levels of APP, IL-1beta, IL-6, TNF-alpha, and CRP in the cerebral cortex and hippocampus and those of PS-1 and PS-2 in the cerebral cortex produced by treatment with CRP or Abeta(25-35). Immunoblotting analysis showed that while expression of APP was increased in both the cerebral cortex and the hippocampus, expression of IL-1beta, BACE, and TNF-alpha was increased only in the hippocampus.

CONCLUSIONS

The results suggest that CRP contributes to memory loss and early phase of pathogenesis of AD. CRP can be a novel target for therapeutic intervention of AD.

Plasma fibrinogen is associated with cognitive decline and risk for dementia in patients with mild cognitive impairment

This study was aimed to investigate the relationship between plasma fibrinogen level and risk for cognitive decline and dementia in patients with mild cognitive impairment (MCI). Elderly patients with suspected cognitive impairment were screened and evaluated periodically. One hundred and eighty-five patients who met the criteria for MCI were enrolled. Blood coagulation functions and plasma fibrinogen levels were measured at baseline. Hyperfibrinogenaemia was defined as plasma fibrinogen > or =3.0 g/l. Global cognitive function was assessed serially with Mini-Mental State Examination (MMSE). The enrolled patients were followed for 2 years to observe if dementia was developed. There were 185 patients diagnosed as MCI, of which 17 (9.2%) deceased, 15 (8.1%) lost to follow-up, and 68 (36.8%) developed dementia during follow-up. Mean of MMSE score of the enrolled patients declined significantly during follow-up (22.0 +/- 3.0 vs. 18.1 +/- 5.8, p < 0.001). Patients with hyperfibrinogenaemia at baseline had greater MMSE decrement during follow-up than patients with normal fibrinogen level (-5.4 +/- 5.4 vs. -3.5 +/- 4.5, p < 0.05). Linear regression indicated that plasma fibrinogen level was associated with cognitive decline (R = 0.17, p < 0.05). Patients with hyperfibrinogenaemia had an increased risk for dementia and vascular dementia compared with patients with normal level of plasma fibrinogen (log rank test, p < 0.05). There was a trend that hyperfibrinogenaemia also increased risk for dementia of Alzheimer's type (p = 0.061). It can be concluded that plasma fibrinogen level may be associated with cognitive decline, and hyperfibrinogenaemia may increase risk for dementia in patients with MCI.

Inflammation and rate of cognitive change in high-functioning older adults

BACKGROUND

Inflammatory proteins including interleukin-6 (IL-6) and C-reactive protein (CRP) have been associated with incident cognitive impairment, but little research has addressed their effects on the rate of cognitive change, and findings are mixed. The purpose of this study was to examine the relationship between serum levels of IL-6 and CRP and the rate of cognitive change across a range of cognitive domains in a sample of healthy older persons.

METHODS

Growth curve analysis was performed on data from the MacArthur Study of Successful Aging, a longitudinal cohort study of high-functioning older adults aged 70-79 years at baseline in 1988 and reinterviewed in 1991 and 1995 (N = 851). Individual growth curve parameters were derived from baseline and follow-up performance in abstraction, language, spatial ability, verbal recall, spatial recognition, and global cognitive function based on age, IL-6, CRP, and covariates.

RESULTS

Cross-sectionally, there is a generally linear negative relationship between inflammation and cognition, such that higher levels of inflammation are associated with lower levels of baseline cognitive function. After controlling for potential confounders, there was no effect of inflammation on baseline cognitive function or the rate of longitudinal cognitive change. However, persons in the top tertile on IL-6 were at an increased risk of incident declines on the Short Portable Mental Status Questionnaire (SPMSQ).

CONCLUSIONS

Although high levels of inflammation are associated with incident cognitive impairment, these results do not generalize to the full range of cognitive changes, where the role of inflammation appears to be marginal.

Help me, Doctor! My D-dimer is raised

Although optimal strategy for management of patients with suspected venous thromboembolism depends on local expertise and cost, diagnostic algorithms including clinical assessment and D-dimer have been validated in several trials. However, a new paradigm shift is emerging, giving an extended role of D-dimer measurement in clinical practice. D-dimer is a useful biomarker to help determine initial anticoagulant therapy in patients with thrombosis. Emerging evidence also endorses a 'predictive' role for raised D-dimer levels, since its measurement provides prognostic indications for a variety of conditions, including venous thromboembolism, disseminated intravascular coagulation, cardiovascular disease, infectious diseases, and cancer. Additional investigation is needed to clarify whether raised D-dimer is an epiphenomenon or it is actively involved in pathophysiology. Further studies are also required to establish whether D-dimer testing, alone or combined with other prognostic indicators, can be used to identify patient candidates for further triage and treatment. Nevertheless, the hazard(s) associated with raised D-dimer in plasma requires re-emphasis in the teaching of post-graduates, junior doctors and medical students, including the most effective treatments to inhibit clot spread and decrease the probability of further significant thrombotic incidents even in the absence of any 'detectable' thrombosis.