When we talk about Alzheimer’s disease we mean the changes in the brain that may lead to Alzheimer’s dementia. An individual can have signs of Alzheimer’s disease in the brain without having Alzheimer’s dementia. Alzheimer’s disease may develop into Alzheimer’s dementia, but does not always do so. Alzheimer’s dementia refers to the clinical syndrome where memory and thinking are impaired to the extent that day-to-day functioning of the individual is affected.
Magnetic Resonance Imaging (MRI) is an established, widely accepted medical way to look in detail at the structure of the brain. MRI is painless, but participants will need to lie still in the scanner for up to 80 minutes and some people can find this claustrophobic. The scanner is also quite noisy, although participants will be wearing ear protection.
The examination included measurement of blood pressure, height, weight, hip and waist circumference. The study doctor also did a full neurological (senses, power, coordination and reflexes) and cardiac examination. Participants were also be asked to provide information about medical history, including family history of dementia, and their current medication(s).
The physical examination was conducted annually while participants were enrolled in the EPAD cohort.
The cognitive assessments were undertaken using a neuropsychological examination assessing reaction time, function, language skills, memory and attention by means of several tests. The study psychologist or research nurse provided clear instructions on how to complete the assessments.
The cognitive tests were conducted at the initial study visit, after six months, and then annually, while participants were enrolled in the EPAD cohort.
Spinal fluid was collected with a procedure called a lumbar puncture. The spinal fluid connects with the spaces within and around the brain so is a very good source of information about what is happening in the brain. This is a commonly conducted test in both research and clinical practice in many parts of Europe.
The procedure takes about an hour in total. Participants are normally be lying on their side, with their legs pulled up and their chin tucked in, but the procedure can also be carried out while they are seated and leaning forwards. Under local anaesthetic, approximately 10 ml of spinal fluid is collected. The lumbar puncture usually takes around 30-45 minutes to complete. After the procedure participants are asked to rest for approximately 30 minutes.
The spinal fluid sample were taken annually while participants were enrolled in the EPAD cohort.
The research was organised in several European countries under the leadership of the University of Edinburgh, Scotland, UK. EPAD was funded by the European Commission and the European Federation of the Pharmaceutical Industry Association (EFPIA) through the Innovative Medicines Initiative Joint Undertaking (IMI JU).