Leblanc, Gabrielle G.

Background and Purpose— One in 3 individuals will experience a stroke, dementia or both. Moreover, twice as many individuals will have cognitive impairment short of dementia as either stroke or dementia. The commonly used stroke scales do not measure cognition, while dementia criteria focus on the late stages of cognitive impairment, and are heavily biased toward the diagnosis of Alzheimer disease. No commonly agreed standards exist for identifying and describing individuals with cognitive impairment, particularly in the early stages, and especially with cognitive impairment related to vascular factors, or vascular cognitive impairment. Methods— The National Institute for Neurological Disorders and Stroke (NINDS) and the Canadian Stroke Network (CSN) convened researchers in clinical diagnosis, epidemiology, neuropsychology, brain imaging, neuropathology, experimental models, biomarkers, genetics, and clinical trials to recommend minimum, common, clinical and research standards for the description and study of vascular cognitive impairment. Results— The results of these discussions are reported herein. Conclusions— The development of common standards represents a first step in a process of use, validation and refinement. Using the same standards will help identify individuals in the early stages of cognitive impairment, will make studies comparable, and by integrating knowledge, will accelerate the pace of progress.

Background and Purpose— This review considers the current state of knowledge of genetic factors underlying vascular cognitive impairment (VCI). Summary of Review— We argue here that genes conferring susceptibility to VCI must be of 2 nonmutually exclusive classes: (1) genes that confer susceptibility to cerebrovascular disease, and (2) genes that determine brain tissue responses to cerebrovascular disease (ie, render parenchymal tissue more or less susceptible to injury or able to repair itself after injury). Although some progress has been made in identifying genes of the first class, little has been done to explore genes of the second class. Evidence for the existence of such genes is presented. We discuss the advantages and disadvantages of different forms of cerebrovascular disease for studying these genes, and different study designs that might be used. Conclusion— The most critical challenge for genetic studies of VCI is to identify quantifiable phenotypes that can be reliably and effectively determined in large samples of subjects.