The apathy, gait impairment, and executive dysfunction (AGED) triad vascular variant

Apathy, gait disturbances, and executive dysfunction (AGED) often occur together. Although they can arise independently, the presence of one might portend another. This recognition suggests the possible etiology. We focus on the most common, the vascular. We explain the AGED vascular mechanism through the ambibaric brain concept. The brain contains two complementary blood pressure systems: One high in the primitive brain (brainstem, basal ganglia, and thalamus) and a low-pressure system in the Homo sapiens brain (cerebral hemispheres). Hypertension inflicts the most damage on the primitive brain. The frontal systems connect to the basal ganglia, then the thalamus and back to the cortex. Many connections converge on the primitive brain where they are damaged by vascular disease. We need methods of determining optimal, individual blood pressures. Although the AGED triad can result from other causes, it should first signal a vascular etiology, the most prevalent, treatable, and preventable one

Cost-effectiveness of cerebrospinal biomarkers for the diagnosis of Alzheimer\u27s disease

Background: Accurate and timely diagnosis of Alzheimer\u27s disease (AD) is important for prompt initiation of treatment in patients with AD and to avoid inappropriate treatment of patients with false-positive diagnoses. Methods: Using a Markov model, we estimated the lifetime costs and quality-adjusted life-years (QALYs) of cerebrospinal fluid biomarker analysis in a cohort of patients referred to a neurologist or memory clinic with suspected AD who remained without a definitive diagnosis of AD or another condition after neuroimaging. Parametric values were estimated from previous health economic models and the medical literature. Extensive deterministic and probabilistic sensitivity analyses were performed to evaluate the robustness of the results. Results: At a 12.7% pretest probability of AD, biomarker analysis after normal neuroimaging findings has an incremental cost-effectiveness ratio (ICER) of $11,032 per QALY gained. Results were sensitive to the pretest prevalence of AD, and the ICER increased to over$ 50,000 per QALY when the prevalence of AD fell below 9%. Results were also sensitive to patient age (biomarkers are less cost-effective in older cohorts), treatment uptake and adherence, biomarker test characteristics, and the degree to which patients with suspected AD who do not have AD benefit from AD treatment when they are falsely diagnosed. Conclusions: The cost-effectiveness of biomarker analysis depends critically on the prevalence of AD in the tested population. In general practice, where the prevalence of AD after clinical assessment and normal neuroimaging findings may be low, biomarker analysis is unlikely to be cost-effective at a willingness-to-pay threshold of $ 50,000 per QALY gained. However, when at least 1 in 11 patients has AD after normal neuroimaging findings, biomarker analysis is likely cost-effective. Specifically, for patients referred to memory clinics with memory impairment who do not present neuroimaging evidence of medial temporal lobe atrophy, pretest prevalence of AD may exceed 15%. Biomarker analysis is a potentially cost-saving diagnostic method and should be considered for adoption in high-prevalence centers

Cost-effectiveness of cerebrospinal biomarkers for the diagnosis of Alzheimer’s disease

Background: Accurate and timely diagnosis of Alzheimer’s disease (AD) is important for prompt initiation of treatment in patients with AD and to avoid inappropriate treatment of patients with false-positive diagnoses. Methods: Using a Markov model, we estimated the lifetime costs and quality-adjusted life-years (QALYs) of cerebrospinal fluid biomarker analysis in a cohort of patients referred to a neurologist or memory clinic with suspected AD who remained without a definitive diagnosis of AD or another condition after neuroimaging. Parametric values were estimated from previous health economic models and the medical literature. Extensive deterministic and probabilistic sensitivity analyses were performed to evaluate the robustness of the results. Results: At a 12.7% pretest probability of AD, biomarker analysis after normal neuroimaging findings has an incremental cost-effectiveness ratio (ICER) of $11,032 per QALY gained. Results were sensitive to the pretest prevalence of AD, and the ICER increased to over$50,000 per QALY when the prevalence of AD fell below 9%. Results were also sensitive to patient age (biomarkers are less cost-effective in older cohorts), treatment uptake and adherence, biomarker test characteristics, and the degree to which patients with suspected AD who do not have AD benefit from AD treatment when they are falsely diagnosed. Conclusions: The cost-effectiveness of biomarker analysis depends critically on the prevalence of AD in the tested population. In general practice, where the prevalence of AD after clinical assessment and normal neuroimaging findings may be low, biomarker analysis is unlikely to be cost-effective at a willingness-to-pay threshold of $50,000 per QALY gained. However, when at least 1 in 11 patients has AD after normal neuroimaging findings, biomarker analysis is likely cost-effective. Specifically, for patients referred to memory clinics with memory impairment who do not present neuroimaging evidence of medial temporal lobe atrophy, pretest prevalence of AD may exceed 15%. Biomarker analysis is a potentially cost-saving diagnostic method and should be considered for adoption in high-prevalence centers

Implementing the Proclamation of Stroke and Potentially Preventable Dementias

Brain health plays a central role in wellbeing and in the management of chronic diseases. Stroke and dementia pose the two greatest threats to brain health, but recent developments suggest the possibility that preventing stroke may also prevent some dementias: 1. A large population study showed a 32% decrease in the incidence of stroke and a concomitant 7% reduction in the incidence of dementia; 2. Treatment of atrial fibrillation resulted not only in stroke reduction, but a 48% decrease in dementia; 3. A hypothesis free analyses has shown that the first phase of Alzheimer disease involves vascular dysregulation, opening the door to new therapeutic approaches; 4. Cognitive impairment, often treatable and reversible, accompanies heart and kidney failure. These developments, combined with the knowledge that stroke, dementia and heart disease share the same major treatable risk factors, particularly hypertension, offers an opportunity for their joint prevention. This aspiration is expressed by a Proclamation of the World Stroke Organization on Stroke and Potentially Preventable Dementias and endorsed by the World Heart Federation, the World Hypertension League, Alzheimer Disease International and 18 other international, regional and national organizations as a call for action

Brain, heart, and sudden death

During the past 30 years, rate of coronary artery disease (CAD), as the main cause of sudden death (SD), has decreased more than rate of SD. Likewise, cause of SD remains elusive in not a trivial portion of its victims. One possible reason is attention to only one organ, the heart, as the cause of SD. In fact, SD literature focuses more on the heart, less on the brain, and seldom on both. A change is required. In this paper, we first review the pathological findings seen in heart autopsies of SD victims after psychological stressors such as physical assault victims without internal injuries. Then, we summarize new studies investigating brain areas, like the insula, whose malfunctions and injuries are related to SD. Next, we review prototypes of neurological diseases and psychological stressors associated with SD and look at heart failure (HF)-related SD providing evidence for the brain-heart connection. Finally, we propose a new look at SD risk factors considering both brain and heart in their association with SD, and review strategies for prevention of SD from this perspective

Pathophysiology of vascular dementia

The concept of Vascular Dementia (VaD) has been recognized for over a century, but its definition and diagnostic criteria remain unclear