Brain Evaluation

WHITE MATTER INJURY IS MARKER FOR AGE RELATED COGNTITVE DECLINE

According to Neurology Today (August 16, 2012) white matter damage or injury is no longer seen as typical aging.  White matter refers to damage to the brain affecting our thinking or cortical brain areas.  White matter is seen as a preclinical marker for cognitive decline and Alzheimer’s disease. 
Microstructural white matter changes are identifying individuals who show no cognitive difficulties to be at risk for mild cognitive decline and dementia.  Suggested is that the disease begins early and ten years before cognitive problems and poor memory are actually apparent (thus the term preclinical) in daily life.  The take away point is that lesions (or impact to brain structures) involving as little as three percent of the white matter produces impairment in working memory in demented individuals.  The diagnosis of vascular dementia is given when there is a clear relationship in the severity and pattern of cognitive impairment and the presence of diffuse subcortical cerebrovascular disease pathology (brain areas affected by the loss of adequate blood flow).   The idea is that age related cognitive decline, a term seen on the MRI test results, is not normal aging and instead a marker of dementia and that further, more often, dementia is a mixed picture of neurodegenerative and vascular (heart related) pathologies.

IN LATE LIFE, LOW BLOOD PRESSURE CAN BE A MARKER FOR DEMENTIA RISK

Blood pressure or arterial blood pressure is the pressure exerted by circulating blood upon the walls of the blood vessels and is one of the principal vita signs of health.  For each heart beat blood pressure varies between a maximum (systolic) and minimum (diastolic) pressure.   We tend to pay more attention to the maximum rather than the minimum blood pressure.  However a sustained lower diastolic blood pressure may actually be a measure of vascular health as we age.  When diastolic blood pressure drops, it may be related to a progression of global and subcortical brain atrophy seen among
middle aged patients with arterial disease. The thought is that vascular disease makes patients more vulnerable to lower diastolic blood pressure and subsequent neurodegeneration.  Subcortical brain volume was actually reduced by 0.8 percent where patients had low diastolic blood pressure.   When individuals who had never been diagnosed with hypertension, had a midlife diagnosis of hypertension, this was associated with increased risk of damage to the brain (cortical and subcortical infarctions) in late life. Midlife hypertension was associated with a 14 percent increase in white matter hyperintensity volume seen on MRI studies.   In individuals with a history of hypertension reduced blood pressure was associated with an increase in the neurodegeneration biomarker CSF phosphate-tau as well as deterioration of episodic memory (memory for events).  Another speculation is that
high midlife blood pressure could increase the risk of cerebral hypofusion resulting in changes in the brain making the brain more vulnerable (Neurology Today, September 20, 2012).

 

DELIRIUM FOLLOWING CARDIAC SURGERY MAY NOT BE A TEMPORARY STATE

Delirium is defined when a person is out of their mind to put it simply, is not oriented, does not know where they are and highly confused.  Delirium which is recognized as a complication often seen resulting from any surgery may actually be the beginning of cognitive decline requiring aggressive
intervention and treatment at the time or shortly after it occurs.  A recent study found that after undergoing cardiac surgery, 46 percent of 225 cardiac surgery patients who were diagnosed
with post-operative delirium were less likely to return to their baseline level of cognitive functioning.  This means that once they had this episode of being incoherent, they never came back to who they were. These patients may need to be more closely monitored after surgery and hospital discharge.  Therapy following discharge may need to be tailored to address cognitive decline and provide cognitive rehabilitation or brain training.  In the hospital setting there are some helpful interventions that can be employed.  Not waking patients up in the middle of the night for tests or procedures to ensure good sleep.  To make sure that patients have their eye glasses or hearing aids on following surgery to prevent disorientation.  Have a clock in their room with the date and news on the television to remind them of what is going on in the world.  Another thought is that delirium developing post-surgery may be the unmasking of cognitive decline and greater vulnerability that is already present in the individual.  Neurology Today, August 16, 2012.

THE IMPACT OF HIGH BLOOD PRESSURE UPON THE BRAIN IN MIDDLE AGE

According to a recent study published in Lancet Neurology in December of 2012, using diffusion tensor
imaging there was greater evidence of white matter damage (especially in the anterior corpus callosum, the inferior fronto-occipital fasciculi and fibers projecting from the thalamus to the superior frontal gyrus) found in individuals as young as forty years old when diagnosed with high blood
pressure.  An association was found between systolic blood pressure and white matter damage in 579 people with a mean age of 39.2 years that are part of a long term heart study.  Elevated blood pressure correlated with greater evidence of white matter damage in areas of the brain that impact
executive reasoning processes.

EARLY MARKER FOR ALZHEIMER’S DISEASE MAY BE DISRUPTED SLEEP WAKE CYCLES

Disrupted sleep seen in animals,either abnormal sleep patterns or sleeping less, resulted in more amyloid beta pathology (a marker for dementia) accumulating in their brain.  The amyloid pathology began at six months and sleep problems started at nine months.  As the abeta accumulated in the brain the amount of time that the animals were awake, doubled.  In other words as this marker for dementia increased so did the sleep problems.  The study suggests that abeta aggregation disrupts the sleep wake cycle and diurnal (daytime) fluctuation of amyloid beta. Another study using human subjects, dementia patients, found that those with amyloid deposition had more sleep wake issues.  In other research it was found that aged individuals, who woke up more frequently, more than five times per hour, were more likely to have abnormal readings on the biomarker studies for Alzheimer’s disease.  Studies illuminate the importance of tracking changes in the sleep wake cycle as an indication of developing dementia. Neurology Today October 4 2012

 

A Drug found to Temporarily Improve Social Behaviors in Frontotemporal Dementia

Oxytocin has been tried successfully with autism and recently was trialed with patients diagnosed with frontal temporal dementia, FTD.  Social behavior is a common consequence of FTD, individuals can become emotionally blunted and withdrawn.  Evidence in the use with autism is that it enhances “relatedness”.  The hormone is thought to enhance positive cues from the environment and to reduce negative ones leading to decreased sensitivity to feeling threatened by the environment.   Time and further research will provide confirmation of whether this drug could be of benefit to those diagnosed with FTD. Neurology Today 1-19-12.

Positive Effects of Nicotine for Neurodegenerative Disorders

Researchers are looking at the positive effect of nicotine on dyskinesias and impulsivity in Parkinson disease, cognitive deficits in ADHD and attention and memory for mild cognitive impairment.  Neurology Today (1-19-12) reports on a recent study published in Neurology involving 67 subjects who participated in a randomized study using the nicotine patch.  The results indicate significant improvement in attention, memory and psychomotor speed.  Nicotinic receptors are seen as regulating other receptor systems like a gain amplifier. 

 

Alzheimer Cascade Starts Two Decades Before Symptoms

Presentation at the neurology conference as interim analysis of data focusing on dominantly inherited Alzheimer disease shows that there is a pathophysiologic cascade leading to the disease that begins to appear 20 years prior to clinical symptoms being seen. Markers include declining left hippocampal volume, increasing presence of tau protein in the CSF and increasing third ventricle volume seen on MRI studies.  Neurology Today, October 20, 2011.  This suggests that small signs of memory changes are very important and not to wait to have neuropsychological testing, to see your primary care physician or neurologist and to strengthen the brain through brain training.

Mild Cognitive Impairment Affects 10 to 20 percent of Older Adults Leaving Them at Risk to Develop Dementia

The presence of mild cognitive impairment (MCI) ranges from 10 to 20 percent of older adults in the United States and Western Europe.  Eighty percent of those diagnosed with MCI are at risk for the diagnosis of dementia in ten years time. (Neurology Today, September 1, 2011)  These dramatic numbers suggest the importance of not waiting for memory issues to become worse and instead to address problems.  Addressing problems early offers the older population the benefit of graceful aging instead of the risk of dementia.  The point being is that there is the opportunity to address memory problems when they are first seen before excuses are made and mistakes due to forgetting are covered up.   Those at risk with MCI can protect their brain with early diagnosis by a neuropsychologist and then seeing their primary care physician or neurologist for medication to prevent further decline.  Brain training helps to bring back memory processes if they are affected and to build brain processes for further prevention.

Age Remains the Single Most Potent Risk Factor for late onset Alzheimer Disease

Age associated decline in health status is a risk factor for Alzheimer’s dementia, age related problems such as heart disease, hypertension, stroke and diabetes are recognized as AD risk factors. Other problems that are common in older people make things worse such as; high plasma cholesterol, morning cough, a sedentary lifestyle, pesticide exposure, dementia in a spouse, feeling tired, lonely and unwell shown to increase the risk of dementia. The idea that emotional and physical frailty are related to dementia.