Cerebral small vessel disease, cognitive reserve and cognitive dysfunction.

The concept of cognitive reserve describes differences between individuals in the ability to compensate age-related brain changes or pathology as a result of greater intellectual enrichment. Cerebral small vessel disease (CSVD) is a common age-related vascular disease of the brain associated with slowly accumulating tissue damage and represents a leading cause of functional loss, disability and cognitive decline in the elderly. The promotion of cognitive reserve might be a valuable possibility to moderate the negative impact of accumulating brain changes associated with CSVD on cognitive function and thus limit the functional consequences of CSVD. We here review existing studies investigating this topic in CSVD and provide conceptual considerations why future research is needed. Relevant studies were identified using the electronic databases PubMed and MEDLINE. Six studies including 7893 subjects were found that all focused on a single feature of CSVD only, i.e., white matter hyperintensities (WMH). We also included one study investigating 247 CADASIL patients. In general, they confirm that higher cognitive reserve (i.e., educational attainment) attenuates the negative impact of WMH on cognition. Further studies should attempt to replicate this association for all features of CSVD and to expand the concept to other areas of functional loss like disordered gait. Finally intervention studies will be needed to define when and how we can still increase our cognitive reserve and what kind and magnitude of protective effects this may offer.