UCL Dementia


Cohort Studies | The Class of '46

The 1946 birth cohort will shed light on the emergence of dementia in the general population. 

In 1946 a remarkable experiment began. All infants born during a single week in March were enrolled in a national maternity survey, generating invaluable data on early health and the cost of childbirth. Subsequently, researchers have continued to follow a subset of these infants, who became the 1946 birth cohort and have gone on to provide unique insight into factors affecting health and wellbeing across the life course. And as cohort members reach their later years, they are yet again contributing to our understanding of disease - this time, early signs of dementia. 

The 1946 cohort, the world's longest running birth cohort, is coordinated by the MRC Unit for Lifelong Health and Ageing (LHA), led by Professor Diana Kuh. From the 5000 or so infants, more than half are still contributing regularly, undergoing periodic health checkups, taking tests of cognition, and contributing medical and lifestyle data. 

As participants reach their late 60s, they have become of increasing interest to the field of healthy ageing. Uniquely, the wealth of data collected over their lifetime can reveal factors influencing health and wellbeing in old age. 

Furthermore, for dementia researchers, the cohort is a golden opportunity to study an entirely unbiased population sample as they begin to show signs of cognitive impairment. Even if symptoms are not apparent, their brains may still be showing the distinctive changes that precede overt loss of cognitive function. 

To gain insight into the changes, 500 cohort members are being invited to participate in a dementia substudy, being led by Professor Marcus Richards at the LHA and Dr Jonathan Schott and Professor Nick Fox in UCL's Dementia Research Centre. Participants will undergo combined PET-MRI scanning, to characterise brain structure and levels of β-amyloid. They will also provide biological samples for biomarker assessment and genetic analysis, and undertake various performance tests. After a baseline scan, study members will be scanned again in two to three years' time. 

The study is a rare opportunity to collect data from large numbers of healthy individuals and to relate them to the subsequent development of disease. In addition, analysis of historical data will also shed light on multiple other factors, from education to blood pressure, that could conceivably affect the onset of symptoms. This most intensively studied group of individuals therefore look set to benefit medicine all the way from cradle to grave.