Cognitive impairment and cardiovascular diseases in the elderly. A heart-brain continuum hypothesis.

The aging population is increasing and, therefore, a higher prevalence of cardiac disease is emerging; including hypertension, coronary artery disease, atrial fibrillation and chronic heart failure. Large cohort studies have revealed a relationship among increased risk for cognitive impairment and dementia in cardiovascular diseases probably due to embolic stroke or chronic cerebral hypoperfusion. Thus, the aim of the present review is to overview the studies that investigate the presence and/or the development of cognitive impairments and dementia in patients with varied types of cardiovascular disease. Finally, a continuum among hypertension, coronary artery disease, atrial fibrillation and chronic heart failure with to the development of cognitive impairment and progression to dementia has been hypothesized.

Autonomic dysfunction in Alzheimer's disease: tools for assessment and review of the literature.

Autonomic dysfunction is very common in patients with dementia, and its presence might also help in differential diagnosis among dementia subtypes. Various central nervous system structures affected in Alzheimer's disease are also implicated in autonomic nervous system regulation, and it has been hypothesized that the deficit in central cholinergic function observed in Alzheimer's disease could likely lead to autonomic dysfunction. Several feasible tests can be used in clinical practice for the assessment of parasympathetic and sympathetic functions, especially in terms of cardiovascular autonomic modulation. In this review, we describe the different tests available and the evidence from the literature which indicate a definite presence of autonomic dysfunction in dementia at various degrees. Importantly, the recognition of dysautonomia, besides possibly being an early marker of dementia, would help prevent the disabling complications which increase the risk of morbidity, institutionalization, and mortality in these individuals.

Role of ventricular rate response on dementia in cognitively impaired elderly subjects with atrial fibrillation: a 10-year study.

BACKGROUND: The role of ventricular rate response (VRr) on the incidence of dementia in elderly subjects with cognitive impairment and atrial fibrillation (AF) is not known. Thus, we examined the ability of VRr to predict dementia in cognitively impaired elderly subjects with and without AF. METHODS: A total of 358 cognitively impaired elderly subjects (MMSE <24) with and without AF were stratified in low/high (<50/>90) and moderate (>50/<90 bpm) VRr. A 10-year follow-up was performed. RESULTS: Cognitively impaired subjects with dementia at the end of the follow-up were 135 (37.7%): 33 in the presence (75.0%) and 102 (32.5%) in the absence of AF (p < 0.001). Multivariate analysis shows that AF is a strong predictor of dementia (hazard ratio, HR = 4.10; 95% confidence interval, CI = 1.80-9.30, p < 0.001). More importantly, low/high VRr (<50/>90 bpm) is predictive of dementia in the presence (HR = 7.70, 95% CI = 1.10-14.20, p = 0.03) but not in the absence (HR = 1.85; 95% CI = 0.78-4.47; p = 0.152) of AF. CONCLUSIONS: This study demonstrates that AF predicts dementia in elderly subjects with cognitive impairment. Moreover, VRr seems to play a key role in the incidence of dementia in cognitively impaired elderly subjects with AF.

Neuropsychiatric symptoms and syndromes in a large cohort of newly diagnosed, untreated patients with Alzheimer disease.

OBJECTIVES: Neuropsychiatric symptoms are common in patients with Alzheimer disease (AD). Treatment for both AD and psychiatric disturbances may affect the clinical observed pattern and comorbidity. The authors aimed to identify whether particular neuropsychiatric syndromes occur in untreated patients with AD, establish the severity of syndromes, and investigate the relationship between specific neuropsychiatric syndromes and AD disease severity. DESIGN: Cross-sectional, multicenter, clinical study. PARTICIPANTS: A total of 1,015 newly diagnosed, untreated outpatients with AD from five Italian memory clinics were consecutively enrolled in the study from January 2003 to December 2005. MEASUREMENTS: All patients underwent thorough examination by clinical neurologists/geriatricians, including neuropsychiatric symptom evaluation with the Neuropsychiatric Inventory. RESULTS: Factor analysis revealed five distinct neuropsychiatric syndromes: the apathetic syndrome (as unique syndrome) was the most frequent, followed by affective syndrome (anxiety and depression), psychomotor (agitation, irritability, and aberrant motor behavior), psychotic (delusions and hallucinations), and manic (disinhibition and euphoria) syndromes. More than three quarters of patients with AD presented with one or more of the syndromes (N = 790, 77.8%), and more than half exhibited clinically significant severity of symptoms (N = 603, 59.4%). With the exception of the affective one, all syndromes showed an increased occurrence with increasing severity of dementia. CONCLUSIONS: The authors' study supports the use of a syndrome approach for neuropsychiatric evaluation in patients with AD. Individual neuropsychiatric symptoms can be reclassified into five distinct psychiatric syndromes. Clinicians should incorporate a thorough psychiatric and neurologic examination of patients with AD and consider therapeutic strategies that focus on psychiatric syndromes, rather than specific individual symptoms.

Lymphocyte G-protein-coupled receptor kinase-2 is upregulated in patients with Alzheimer's disease.

Alterations in signal transduction pathway of G-protein-coupled receptors (GPCRs) have been found in the cerebrocortex and in the peripheral cultured tissues of patients with Alzheimer's disease (AD). The G-protein-coupled receptor kinase-2 (GRK2) plays an important role in regulating the GPCRs signaling: its increased expression is associated with receptor desensitization. The aim of this study was to explore GRK2 levels in peripheral lymphocytes of AD patients and to establish a correlation between lymphocyte protein concentrations and the degree of cognitive impairment. GRK2 mRNA and protein expression were evaluated in the lymphocytes of AD patients with mild or moderate/severe cognitive impairment and in age-matched healthy subjects. Both GRK2 mRNA and protein expression were higher in AD patients lymphocytes compared to controls. Furthermore, lymphocyte GRK2 levels were significantly correlated to the degree of cognitive decline. Our preliminary data suggest that GRK2 is involved in GPCRs coupling dysfunction observed in AD patients. Further studies are needed in order to verify whether the lymphocyte GRK2 might be utilized as a novel biomarker in AD diagnosis and clinical monitoring.