Cognitive Decline and Dementia Related to Cerebrovascular Diseases: Some Evidence and Concepts

Abstract
Background: Cerebrovascular diseases (CVDs) are considered the second most common cause of cognitive decline in the elderly after neurodegeneration of the Alzheimer’s type. Despite impressive epidemiological data, the actual burden of CVDs in terms of cognitive decline is still incompletely appreciated by physicians and health regulators. Methods: In this brief position paper, we review some evidence related to the topic and its clinical relevance, and we present some concepts that we consider of crucial importance for the correct recognition of the problem. Results and Conclusions: We conclude that: (1) different approaches to the topic exist (clinical, neuroimaging-based, pathological) and the inconsistent use of one or another, together with lack of definitions, has limited the appreciation of the contribution of CVDs to cognitive decline; (2) cognitive impairment related to CVDs is very frequent and constitutes a topic with high epidemiological impact; (3) cognitive impairment associated with CVDs is heterogeneous in clinical and pathogenic terms; (4) vascular lesions often interact with other type lesions, the most important of which are today considered those of the Alzheimer’s type, in determining cognitive impairment; (5) for some vascular lesions, namely white matter lesions and lacunar infarcts, strong evidence suggests their role as determinants of cognitive decline; (6) cognitive impairment is only part of the consequences of CVDs as it is almost invariably accompanied by gait disturbances, depressive symptoms, and sphincteric control dysfunction, all factors contributing to loss of independence.