Changing demographics and the impact on dementia Fiona Matthews MRC Biostatistics Unit, Cambridge Institute of Health and Society, Newcastle University

Population change

Population change

Background Number of cases of dementia worldwide projected to triple by 2050 Europe a doubling of AD (approximately 60% of dementia) to 15.9 million by 2040 Models suggest primary prevention rather than treatment most likely to delay onset Some suggested that up to 50% of dementia is caused by modifiable risk factors

Risk factor changes Factors expected to increase dementia prevalence Physical inactivity Obesity Diabetes Longer survival after stroke Shift in age distribution Inequalities in health across lifespan Factors expected to decrease dementia prevalence Prevention of heart disease Early life education Reduction in stroke

Modifiable risk factors Norton et al 2014

Impact of risks Norton et al 2014

CFAS I and CFAS II Originally set up in six areas– sampling from whole population geographically Three taken forward for new study Cambridgeshire (Ely and surrounding area) Newcastle Nottingham Equal numbers in 65-74 and 75+ year age groups Complete population (including care homes) CFAS I 7640 individuals interviewed (80% response) in 1991-1994 Two stage – screen then assessment 1457 individuals with diagnostic assessment CFAS II 7796 interviews (56% response) in 2008-2011 One interview (screen and assessment combined) All individuals with diagnostic assessment

Changes over last 20 years

Men Women

Men Women

Care settings

Care settings

Projections 1991 prevalence 7.2%, total number 664,000 Apply 2011 age structure Estimate 2011 prevalence Projected 2011 prevalence 8.3%, total 884,000 Undertake new study CFAS II 2011 prevalence 6.5%, total 670,000 Significant reduction of dementia (OR=0.7, 95% CI 0.6-0.9)

Conclusions Dementia prevalence has declined over the last 20 years Number with dementia in UK remained constant despite more older people Large variability still seen Between men and women With deprivation Future work to investigate risk factor profiles and population risk

CFAS I and CFAS II