Abstract
In the next 10 years the number of Dutch people aged 65 and over will increase with 650,000 to 3.0 million people. The prevalence of multiple and often interacting problems in elderly people is high and have many adverse effects on health and quality of life. However, most research and guidelines are directed at isolated health problems. Therefore the research in this thesis is directed towards the interplay between gait and cognition, which both are highly prevalent in old age, have a great impact on the quality of life and functioning of older people and their carers and increase the risk of falling. In this thesis methods to investigate gait and cognitive function and their possible interplay are investigated. It can be concluded that impairments in gait and cognition too often co-occur to be just determined by coincidence. Literature together with the results of this thesis supports the hypothesis that gait and cognition influence each other in older people. They probably have a shared pathophysiology and treatment given for a cognitive problem, for example antipsychotics, can also influence gait. Cognitive functions that seem involved in the coordination of gait and balance are division of attention and insight in cognitive and physical abilities in the cognitive regulation of walking. Executive functions, such as planning and mental flexibility, are also involved and better executive functioning is associated with better gait and balance performance during walking with a cognitive dual task. Although numerous questions are still open, enough knowledge is already present to be able to recommend: If gait is impaired also assess cognitive function and if cognitive function is impaired, also assess gait!
