Epidemiology is the study of patterns of health and illness and associated factors in populations. The Cam-CAN epidemiology cohort will aim to collect information on approximately 3000 adults (aged 18 years and older) living in the Cambridge City area. Respondents will be selected at random from the population registered with Cambridge City GP surgeries. The respondents will be interviewed in their own homes and will answer a range of questions on demographic information, diet, alcohol, smoking, health problems and, for the older participants, questions on how they manage at home with day to day tasks. There is also an extensive cognitive battery measuring memory, language, executive function and various other cognitive domains. Also included within the interview are objective tests such as reaction time, hearing tests and physical measures. All this information provides a rich description of the population from which the Cam-CAN 700 cohort will be selected. The knowledge of the whole population will enable a deeper understanding of the information provided by the 700 in terms not only of the interdisciplinary questions already mentioned, but also by direct linkage back to the general population to enable questions relevant to public health to be investigated. The description of health and well being including “lifestyle” measures from the first interview will also be of direct value in understanding the current picture in Cambridge city.
Current investigations
Each interviewed participant provides a rich dataset with hundreds of measures. Some of the factors expected to impact on performance include mental health measures such as anxiety and depression, and lifestyle measures such as activity levels, diet and sleep patterns.
1. Depression: For example, data from the Hospital Anxiety and Depression Scale, allows us to track symptoms of depression and anxiety across the life span. Specifically, we aim to investigate the association of cognitive functioning (as predicted by measures of reasoning included in the Cam-CAN study such as the Addenbrooke’s Cognitive Examination-Revised (ACER) and Cattel) and depressive and anxious symptomatology. This is, to our knowledge the first investigation of these potential associations across such a wide range of functionality and age. Depression scores will be related to specific cognitive tasks but also to general cognitive health as measured by the ACER, and fluid intelligence measures such as Cattell, which assesses abstract reasoning ability and may be more closely associated with the type of cognitive deficits experienced in those with symptoms of anxiety and depression.
2. Sleep: Another line of investigation is directed at the role of sleep in both cognitive and emotional functioning. Previous research clearly shows laboratory effects of sleep on cognitive function and also on the integration of cognitive and emotional control processes. However, there is a paucity of research investigating sleep with such a thorough inventory of cognitive function and both self-reported mental health and emotion regulatory success on an ecologically valid task of emotion regulation. Cam-CAN participants provide self-report measures of a number of aspects of sleep patterns, yielding measures like sleep efficiency. Preliminary results suggest the expected decline in sleep efficiency with age, and a relationship between declining sleep efficiency and increased anxiety and depression. This interaction between sleep patterns and emotional help will inform future analyses of cognitive and brain function.