Putative mechanisms of cognitive decline with implications for clinical research and practice

Multiple intrinsic and extrinsic mechanisms contribute to vulnerability of cognitive decline and nurses play a significant role in assisting individuals and families to use strategies for healthy cognitive aging. The objective of this narrative review is to provide a synthesis of the intrinsic and extrinsic mechanisms of cognitive decline and conditions that are associated with cognitive decline. Well‐established intrinsic mechanisms of cognitive decline include aging, apolipoprotein E (APOE) ε4 carrier status, SORL1 mutations, neuroinflammation, mitochondrial dysfunction, amyloid deposition, and demyelination. Extrinsic risk factors include obesity, diabetes, hypertension, elevated lipid panel, metabolic syndrome, depression, traumatic brain injury, substance use, heart failure, and stroke. The various definitions of cognitive decline as well as the intrinsic and extrinsic factors that impact cognition as humans age should be incorporated in future clinical research studies. Nurses may use this information to help patients make lifestyle choices regarding cognitive health.     

A Conceptual Model of Cognitive Deficits in Chronic Heart Failure

PURPOSE: To describe a conceptual model to guide studies of cognitive deficits among patients with heart failure. ORGANIZING FRAMEWORK: The conceptual framework of cognitive deficits in chronic heart failure is based on theoretical and empirical literature about (a) the pathophysiology of heart failure, (b) the pathophysiology of cognitive deficits, and (c) health-related quality of life. Other variables that may cause or contribute to cognitive deficits include age, the relative contributions of multiple comorbid conditions, hypertension, and depressive symptoms. Covariates that might influence cognitive deficits (medications, gender, and education) are also included in the model. The most prominent cognitive deficits are believed to occur in domains of attention, working memory, memory, learning, executive function, and psychomotor speed. The main outcome variable is health-related quality of life, which is believed to be influenced by circulatory insufficiency and cognitive deficits. CONCLUSIONS: The conceptual model described in this paper is a framework for testing cognitive deficits that occur in heart failure. After validation through empirical testing, the model may be useful in developing interventions for patients with heart failure whose care is complicated by cognitive deficits.     

2型糖尿病认知障碍患者的磁共振成像研究进展

2型糖尿病(type 2 diabetes mellitus,T2DM)会导致大脑结构和功能异常,增加认知障碍的风险.但是,目前我们对T2DM认知障碍发病机理仍不清楚.而磁共振成像研究的进展进一步确定了T2DM导致认知障碍的相关神经因素.我们系统地回顾了有关T2DM患者神经影像学改变的文献,这些改变包括结构、大脑功能以...     

Interaction of Cognitive Distortions and Cognitive Deficits in the Formulation and Treatment of Obsessive–Compulsive Behaviours in a Woman with an Intellectual Disability

Aims This case study describes the formulation and cognitive–behavioural treatment (CBT) of obsessive–compulsive thoughts and behaviours in a woman with an intellectual disability. The report aimed to distinguish the cognitive deficits that reflect her disability from the cognitive distortions integral to her obsessive–compulsive disorder. Case study Hence, we present one account of the cognitive–behavioural interventions aimed at correcting the cognitive distortions, and a separate account of the modifications necessary to compensate for specific cognitive deficits, which include impairments not only of ‘cognitive therapy skills’, but also of aspects of memory and executive functioning skills. Discussion We suggest that this analysis may provide a rational approach to the problem of simplifying CBT to meet the needs of people with intellectually disabilities, by identifying more clearly the specific adaptations that are needed by a particular individual. We also discuss the assessment of cognitive deficits that might impact on CBT, and some implications of this approach for research and training.     

Cognitive disturbance in hospitalized and institutionalized elders

The purpose of this study was to examine the relationship between empirical findings and a theoretical model of cognitive disturbance among 94 hospitalized and 78 institutionalized elders. Path analysis was used to determine the magnitude of relationships between variables described in the model. Neural function was the only variable in both groups that was significantly associated with greater cognitive disturbance. In the hospitalized group, neural structural changes and physiologic alterations contributed indirectly to cognitive disturbance by their effects on neural function. Further, neural function indirectly affected cognitive disturbance through its effects on sensory deficits. In the institutionalized group, environmental deficits and neural functions were significantly related to greater cognitive disturbance. Except for the direct effects of neural function on activity limitations and physiologic alterations on mental health, all the relationships between the variables described by the model were significantly different between hospitalized and institutionalized elders. The results suggest that different interventions to reduce cognitive disturbances may be required for institutionalized and hospitalized elders.     

The impact of inflammation on cognitive function in older adults: implications for healthcare practice and research

Accumulating evidence suggests that levels of inflammation, an immune response, increase with age throughout the body and the brain. The effects of inflammation on the brain, both acute and chronic, have been associated with cognitive decline and risk of dementia in older adults. Factors believed to increase inflammation include certain health-related behaviors, such as smoking, poor diet, and inactivity as well as health conditions like diabetes, hypertension, and chronic obstructive pulmonary disease, most of which require medical intervention and monitoring. As such, nurses and healthcare professionals are likely to encounter patients who are at a high risk for future development of inflammation-related cognitive decline. A review of inflammatory processes and their relation to cognitive function in older adults is provided, along with factors that may increase or reduce inflammation. Implications for practice and research are discussed.     

Influence of Type 2 Diabetes on Brain Volumes and Changes in Brain Volumes: Results from the Women’s Health Initiative Magnetic Resonance Imaging Studies

OBJECTIVE

To study how type 2 diabetes adversely affects brain volumes, changes in volume, and cognitive function.

RESEARCH DESIGN AND METHODS

Regional brain volumes and ischemic lesion volumes in 1,366 women, aged 72–89 years, were measured with structural brain magnetic resonance imaging (MRI). Repeat scans were collected an average of 4.7 years later in 698 women. Cross-sectional differences and changes with time between women with and without diabetes were compared. Relationships that cognitive function test scores had with these measures and diabetes were examined.

RESULTS

The 145 women with diabetes (10.6%) at the first MRI had smaller total brain volumes (0.6% less; P = 0.05) and smaller gray matter volumes (1.5% less; P = 0.01) but not white matter volumes, both overall and within major lobes. They also had larger ischemic lesion volumes (21.8% greater; P = 0.02), both overall and in gray matter (27.5% greater; P = 0.06), in white matter (18.8% greater; P = 0.02), and across major lobes. Overall, women with diabetes had slightly (nonsignificant) greater loss of total brain volumes (3.02 cc; P = 0.11) and significant increases in total ischemic lesion volumes (9.7% more; P = 0.05) with time relative to those without diabetes. Diabetes was associated with lower scores in global cognitive function and its subdomains. These relative deficits were only partially accounted for by brain volumes and risk factors for cognitive deficits.

CONCLUSIONS

Diabetes is associated with smaller brain volumes in gray but not white matter and increasing ischemic lesion volumes throughout the brain. These markers are associated with but do not fully account for diabetes-related deficits in cognitive function.Many interrelated factors adversely affect the brain health of individuals with type 2 diabetes, including energy dysregulation, inflammation, reduced perfusion, and increased oxidative stress and protein deposition (1,2). In cross-sectional studies, type 2 diabetes is often associated with smaller brain volumes and, less consistently, with greater amounts of white matter hyperintensities and other markers of cerebrovascular disease (3,4). Two longitudinal magnetic resonance imaging (MRI) studies have documented increased rates of total brain atrophy, which appeared to be greater among individuals with lower cognitive function, but not increased accumulations of white matter hyperintensities (5,6). The relative increases in atrophy associated with diabetes remained after covariate adjustment for many risk factors for cognitive dysfunction, including age, blood pressures, education, lipid levels, and BMI.This article is organized with three aims. In a large cohort of older women, we first describe the cross-sectional associations that diabetes had with brain tissue volumes and ischemic lesion loads. We do so for the whole brain and separately for white matter, gray matter, and major lobes. Second, among the women assessed longitudinally with MRI, we examine whether changes in brain tissue and ischemic lesion volumes varied according to diabetes status. Finally, we examine associations that brain volumes and ischemic lesion volumes had with global cognitive function and its subdomains and examine the degree to which they account for diabetes-related relative deficits. There has been one report that diabetes is associated with greater adverse effects on changes in brain structure among women than men (5), perhaps because diabetes often co-occurs with relatively more vascular risk factors among women with versus without diabetes than is the case among men (7). We analyze data from the first sufficiently large cohort of women to characterize the extent to which diabetes-related brain changes account for relative cognitive deficits.     

Effect of pioglitazone on the drivers of cardiovascular risk in type 2 diabetes

The prevalence of type 2 diabetes and its associated mortality and morbidity are continuing to increase across the world. People with type 2 diabetes typically have a cluster of risk factors for cardiovascular disease, including hyperglycaemia, hypertension and lipid abnormalities, which contribute to the high cardiovascular morbidity and mortality in these patients. Targets for glycosylated haemoglobin, lipids and blood pressure are becoming more stringent, and most patients will require multiple therapies to maximally reduce cardiovascular risk. In a large randomised, controlled, long-term cardiovascular outcomes study pioglitazone showed durable glycaemic control, a powerful insulin-sparing effect and changes in the lipid profile associated with reduced cardiovascular risk. This article reviews these metabolic findings in the context of previous randomised, controlled studies for pioglitazone and discusses whether the integration of this agent into the treatment regimen of appropriate patient groups has the potential to improve cardiovascular outcomes in type 2 diabetes.     

HDL dysfunction in diabetes: causes and possible treatments

HDL is known to be inversely correlated with cardiovascular disease due to its diverse antiatherogenic functions. These functions include cholesterol efflux and reverse cholesterol transport, antioxidative and anti-inflammatory activities. However, HDL has been shown to undergo a loss of function in several pathophysiological states, as in the acute phase response, obesity and chronic inflammatory diseases. Some of these diseases were also shown to be associated with increased risk for cardiovascular disease. One such disease that is associated with HDL dysfunction and accelerated atherosclerosis is diabetes mellitus, a disease in which the HDL particle undergoes diverse structural modifications that result in significant changes in its function. This review will summarize the changes that occur in HDL in diabetes mellitus and how these changes lead to HDL dysfunction. Possible treatments for HDL dysfunction are also briefly described.     

Anxiety, panic disorder and coronary artery disease: issues concerning physical exercise and cognitive behavioral therapy

Psychological factors such as stress and depression have already been established as primary and secondary cardiovascular risk factors. More recently, the role of anxiety in increasing cardiac risk has also been studied. The underlying mechanisms of increased cardiac risk in panic disorder patients seem to reflect the direct and indirect effects of autonomic dysfunction, as well as behavioral risk factors associated with an unhealthy lifestyle. Implications of the comorbidity between panic and cardiovascular disease include higher morbidity, functional deficits, increased cardiovascular risk, and poor adherence to cardiac rehabilitation or exercise programs. This article probes the most recent evidence on the association between coronary artery disease, anxiety and panic disorder, and discusses the potential role of incorporating regular physical exercise and cognitive behavioral therapy in the treatment of this condition.     

Menopause and cardiovascular disease.

As the life expectancy of women increases, a greater percentage of women's lives will be spent in the menopause. The greatest cause of morbidity and mortality during that period is cardiovascular disease. The associated risks that predispose to the development of cardiovascular disease are multifactoral and include hypertension, diabetes mellitus, smoking, obesity, family history, and elevated cholesterol levels. The menopause, per se, is associated with an increased risk because of the unfavorable changes in cholesterol metabolism secondary to estrogen deprivation. The replacement of estrogen to menopausal women is believed to improve the lipid profile and reduce the atherogenic changes that increase the risk of cardiovascular disease. However, this form of preventative therapy is futile unless other factors that promote cardiovascular disease also are modified. Such modification may be achieved by following a well-balanced diet, combined with an exercise program, cessation of smoking, weight control, and the monitoring of blood pressure and diabetes in high-risk patients.     

稳定性冠状动脉心脏病患者心绞痛程度与其认知功能的相关性研究

目的分析稳定性冠状动脉心脏病(stable coronary artery disease,SCAD)患者心绞痛(angina pectoris,AP)程度与其认知功能的相关性,探索不同AP程度的SCAD患者认知功能下降领域。方法 2015年11月至2016年6月采用方便抽样法选取上海市某三级甲等医院心内科SCAD住院患者177例为研究对象,使用蒙特利尔认知评估量表(北京版)进行横断面调查。结果运用多元线性回归分析,校正年龄、性别、文化程度、体质指数、是否独居、心肌梗死史、高血压、糖尿病患病情况后,SCAD患者AP程度与总体认知功能及除定向力外的6个认知领域均存在相关性(均P0.05)。多因素调整后,与无AP者相比,轻度AP者与重度AP者认知功能总分分别降低1.3分(P=0.017)和3.3分(P0.001);与无AP者相比,轻度AP者在注意力、语言、抽象思维、定向力等4个认知领域得分降低,重度AP者7个认知功能领域得分均降低,差异均有统计学意义(均P0.05)。结论 AP程度是SCAD患者认知功能下降的独立危险因素,不同AP程度的患者认知功能下降领域不同。     

Cardiovascular disease in diabetic patients

Cardiovascular disease is the most frequent cause of morbidity and mortality in patients with diabetes. This article evaluates the results of clinical interventions that have been tested for their ability to ameliorate cardiovascular disease through identification and management of cardiovascular risk factors. These include hyperglycemia, insulin resistance, dyslipidemia, hypertension, cigarette smoking, and a procoagulant state. Attention to all cardiovascular risk factors is necessary if physicians are to reduce the burden of these complications in diabetic patients.     

Factors related to cognitive status among elders in southern Thailand

Abstract   This study examined the prevalence of and risk factors predicting cognitive impairment among elders in southern Thailand. Four-hundred Thai elders were administered five interview-based questionnaires that assessed demographic characteristics, cognitive function, depression, independent activities of daily living, and social connections. Although most of the elders had normal cognitive function, ∼ 15% experienced cognitive impairment. Though nine of the 10 risk factors examined were identified as being associated with cognitive impairment, only a lack of formal education, female gender, depression, and physical inactivity were found to be significant predictors of cognitive impairment. The results suggested that elders with risk factors should be assessed for cognitive impairment. Depression, and deficits in activities of daily living and educational activities should be addressed and corrected to improve elders' cognitive abilities.     

Cardiovascular risk factors and dementia

Background: Dementias, such as Alzheimer's disease (AD) and vascular dementia, are disorders of aging populations and represent a significant economic burden. Evidence is accumulating to suggest that cardiovascular disease (CVD) risk factors may be instrumental in the development of dementia.Objective: The goal of this review was to discuss the relationship between specific CVD risk factors and dementia and how current treatment strategies for dementia should focus on reducing CVD risks.Methods: We conducted a review of the literature for the simultaneous presence of 2 major topics, cardiovascular risk factors and dementia (eg, AD). Special emphasis was placed on clinical outcome studies examining the effects of treatments of pharmacologically modifiable CVD risk factors on dementia and cognitive impairment.Results: Lifestyle risk factors for CVD, such as obesity, lack of exercise, smoking, and certain psychosocial factors, have been associated with an increased risk of cognitive decline and dementia. Some evidence suggests that effectively managing these factors may prevent cognitive decline/dementia. Randomized, placebo-controlled trials of antihypertensive medications have found that such therapy may reduce the risk of cognitive decline, and limited data suggest a benefit for patients with AD. Some small open-label and randomized clinical trials of statins have observed positive effects on cognitive function; larger studies of statins in patients with AD are ongoing. Although more research is needed, current evidence indicates an association between CVD risk factors—such as hypertension, dyslipidemia, and diabetes mellitus—and cognitive decline/dementia.Conclusions: From a clinical perspective, these data further support the rationale for physicians to provide effective management of CVD risk factors and for patients to be compliant with such recommendations to possibly prevent cognitive decline/dementia.118)     

Autistic disorder: a neuropsychological enigma.

Autism is increasingly viewed as an expression of an unidentified neurological disorder. Because understanding of neurological dysfunction is basic to evaluation and treatment in occupational therapy, this article provides a comprehensive and critical review of the literature since 1985 concerning the neuropsychology of autistic disorder. The research is categorized into four basic types: (a) neuropsychological testing of functional abilities, (b) treatment studies based on neuropsychological hypotheses, (c) autistic-related diseases and genetic disorders, and (d) neuroanatomical and neurophysiological studies. The research shows a spectrum of neurological impairments within the brain stem, cerebellum, midbrain, and frontal lobe. These impairments are associated with deficits in socioemotional skills, sensory processing, motor planning, and cognitive flexibility. This research suggests that persons with autistic disorder need evaluation and treatment of a wide spectrum of functional deficits.     

Evaluating the Dimensionality of Perceived Cognitive Function

Decrements in cognitive function are common in cancer patients and other clinical populations. As direct neuropsychological testing is often not feasible or affordable, there is potential utility in screening for deficits that may warrant a more comprehensive neuropsychological assessment. Furthermore, some evidence suggests that perceived cognitive function (PCF) is independently associated with structural and functional changes on neuroimagery, and may precede more overt deficits. To appropriately measure PCF, one must understand its components and the underlying dimensional structure. The purpose of this study was to examine the dimensionality of PCF in people with cancer. The sample included 393 cancer patients from four clinical trials who completed a questionnaire consisting of the prioritized areas of concerns identified by patients and clinicians: self-reported mental acuity, concentration, memory, verbal fluency, and functional interference. Each area contained both negatively worded (i.e., deficit) and positively worded (i.e., capability) items. Data were analyzed by using Cronbach's alpha, item-total correlations, one-factor confirmatory factor analysis, and a bi-factor analysis model. Results indicated that perceived cognitive problem items are distinct from cognitive capability items, supporting a two-factor structure of PCF. Scoring of PCF based on these two factors should lead to improved assessment of PCF for people with cancer.     

老年男性Ⅱ型糖尿病患者认知功能改变的初步分析及护理

目的 探讨老年男性糖尿病患者认知损伤的特点，为护士制订病人认知功能训练计划提供理论依据。方法 糖尿病患者43例，对照组50例，进行总体认知功能、词语学习、词语记忆、词语再认、视觉记忆、思维判断、空间技能、词语流畅、加工速度、空间执行功能等认知测试。结果 老年男性糖尿病患者简易智力状态检查（MMSE）成绩、学习能力、画钟表测验成绩显著低于正常对照组（P〈0．05）。老年男性糖尿病患者的认知功能成绩与糖尿病病程、发病年龄、伴随的脑梗死、心肌梗死、高血脂、高血压病无关。结论 老年男性糖尿病患者存在以学习和执行功能为主的认知功能减退。认知功能减退与所伴随的脑梗塞、心肌梗塞、高血脂、高血压病无关。     

Diabetes and cardiovascular diseases

Diabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetic people have cardiovascular disease (CVD) risk factors comparable to those of nondiabetics who have had a myocardial infarction or stroke. Physiologic changes in diabetic hypertensive people include endothelial dysfunction, altered platelet activity, and microalbuminuria, all of which may increase coronary heart disease risk. Hyperglycemia and dyslipidemia have been shown to effect physiologic changes in the vasculature; therefore, establishing normoglycemia, reducing cholesterol levels, and controlling blood pressure are the primary and initial goals in the management of diabetic hypertensive patients. The atherosclerotic risk is greatest in poorly controlled patients, possibly because of associated hypercholesterolemia and hypertriglyceridemia. Aggressive management of risk factors such as hypertension, dyslipidemia, and platelet dysfunction in diabetics has been shown to reduce morbidity and mortality in prospective randomized controlled clinical trials. In this article we review the impact of diabetes mellitus on cardiovascular morbidity and mortality.     

The role of cognitive remediation in childhood cancer survivors experiencing neurocognitive late effects.

With the increasing number of children becoming long-term cancer survivors, it has become evident that these survivors are experiencing long-term neurocognitive deficits. Many of these deficits have been found to be the result of cancer-related therapies including intravenous and intrathecal chemotherapy and cranial radiation. These neurocognitive deficits include learning disabilities, cognitive deficits, attention disorders, and difficulties with memory. Cognitive remediation therapy uses a systematic approach to learning strategies that is aimed to equip these affected children with proper, effective, and proven learning strategies. This article will briefly discuss the neurocognitive deficits experienced by long-term childhood cancer survivors. Cognitive remediation therapy will then be introduced with specific attention to the cognitive remediation program developed by Butler and Copeland. Finally, implications for practice and future research will be discussed.