- Neurobehavioral Associates, P.C., Chicago, USA
- Department of Psychiatry, University of Illinois, Chicago, IL, USA
Alissa H. Wicklund
Department of Psychiatry, University of Illinois, Chicago, IL, USA
DOI:10.4103/2152-7806.90030Copyright: © 2011 Wicklund AH. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
How to cite this article: Wicklund AH, Gaviria M. Closing the gap between research techniques and clinical practice in the treatment of dementia. Surg Neurol Int 19-Nov-2011;2:168
How to cite this URL: Wicklund AH, Gaviria M. Closing the gap between research techniques and clinical practice in the treatment of dementia. Surg Neurol Int 19-Nov-2011;2:168. Available from: http://sni.wpengine.com/surgicalint_articles/closing-the-gap-between-research-techniques-and-clinical-practice-in-the-treatment-of-dementia/
Alzheimer's disease (AD) and vascular disease represent the most common causes of dementia in the elderly, with estimates of over 35 million individuals suffering from dementia, primarily of the Alzheimer's type, worldwide.[
The pathology of AD, amyloid plaques and neurofibrillary tangles has an initial affinity for limbic regions that are involved in the cognitive processes of episodic memory.[
Neuroimaging increasingly plays a role in the identification of prodromal stages of AD dementia for research purposes. For example, MRI is utilized to analyze cortical thickness and gray matter atrophy in specified regions of interest such as temporal and parietal brain areas that subserve memory function and can be compared between individuals with AD, MCI and cognitively normal healthy older adults.[
Vascular dementia (VaD) (in the literature, also referred to as multi-infarct dementia and subcortical ischemic vascular disease,[
The disparity between research and clinical implementation of imaging and biomarkers as diagnostic tools in dementia is being addressed through clinical trial outcome studies. Programs such as the Alzheimer's Disease Neuroimaging Initiative (ADNI),[
One issue is the lack of imaging tools commercially available to clinicians. For example, hippocampal and entorhinal volumetric measurements on MRI have been shown to be useful in identifying incipient dementia and tracking volumetric change over time using voxel-based morphometry.[
Another barrier in applying neuroimaging techniques to clinical practice is that even if the techniques could improve diagnostic accuracy, there is currently a lack of pharmacologic treatments available for dementia. However, increased diagnostic accuracy can still be useful in the tracking and staging of illness caused by neurodegenerative disease and measuring outcomes of neurosurgical procedures in dementia resulting from INPH. Acknowledging the level of the disease process can inform decisions regarding the patients’ functional abilities and psychiatric treatment, and provide information for family education and intervention.
As described, current research is focusing more on the early stages of neurodegeneration by examining the biomarkers and risk factors for dementia that may present even decades before clinical symptoms appear.[
Another barrier to bridging the gap between research and clinical practice is in the area of insurance and healthcare coverage, particularly in the United States healthcare system. Healthcare does not yet recognize many of these techniques for early stage diagnosis and treatment planning, as to date many of the techniques are still in experimental stages. If imaging could be applied to track and stage a future neurodegenerative condition, earlier intervention may be possible. Even for those individuals with suspected clinical dementia syndromes, insurance coverage for currently approved imaging techniques is not universal. For example, some insurance plans cover the cost of PET in the differential diagnosis of AD versus frontotemporal lobar degeneration (a neurodegenerative disease typically presenting in individuals before the age of 65, characterized by symptoms of progressive decline in behavior and/or language). Other insurance carriers have limitations on the age group or diagnostic categories in which they determine advanced imaging to be clinically useful.
New neuroimaging techniques continue to emerge and advance our tools for the assessment, diagnosis, tracking and staging of dementia. Programs such as ADNI have an impact by validating the utility of these techniques for clinical trials. With organized large-scale validation trials, clinicians can remain hopeful that imaging vendors may also see the utility of such techniques and prepare more readily available commercial software for image analysis. The insurance industry will also need to make strides to offer reimbursement for such techniques. However, a gap to implementation still exists in countries without resources to fund such advanced tools. Thus, developing countries will continue to rely on clinical acumen and cognitive screening batteries, which are ultimately the most readily available and applied tools, and most useful in terms of guiding treatment planning, family education and assessing functional ability in individuals with dementia.
With collective support from imaging vendors, insurance companies, researchers and organized professional societies, such as the International Neuropsychiatric Association, American Neuroradiological Society, Society for Nuclear Medicine, American Association of Neurological Surgeons, the Alzheimer's Association and others, we can see individual patients benefit through more comprehensive clinical care, with the goal of diminishing the gap between research techniques and clinical practice.
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