The New Therapeutics in Alzheimer's disease study (NTAD for short) has been running for several years. There is still an urgent need for better diagnosis and treatment for dementia. One problem is that clinical trials have just been too slow, expensive and uncertain. NTAD has been looking at a way that can reduce the cost, risk and time it takes to get safe and effective new drugs. Our main research has been to test a new type of brain scanner called MEG, to see if it can pick up the effect of Alzheimer's over time on brain health. Nearly 150 people have taken part in the NTAD study which has shown that the MEG scan works in detecting Alzheimer's disease, and changes over a year, person by person. A critical step was to show that MEG scans give the same result every time, called reliability. This is needed, to detect the benefit from a new drug. Here Yasir Widatalla and Cara Alcock describe how the study was delivered.
The NTAD team wanted to recruit people over 50 who had a diagnosis of Mild Cognitive Impairment or Alzheimer's Disease ('patient group'), and people with no history of dementia ('control group') to compare results. Most volunteers were found through memory clinics in Cambridge and Oxford or from Join Dementia Research UK
Volunteers were first contacted by phone to discuss the study. If they were a good fit for the study, we met in-person for "screening" to check safety and eligibility. We looked at the diagnosis, took a blood sample for chemical and genetic analysis, and gave questionnaires about memory and general well-being.
For the next step volunteers chose between a lumbar puncture to collect spinal fluid or a PET scan. Both the PET scans and spinal fluid tests confirm the presence of Alzheimer's disease in the brain, as a gold-standard against which we can compare the MEG scan. They also rule out illnesses that can mimic Alzheimer's disease.
Afterwards, the volunteers had a MEG scan to measure the tiny electric and magnetic activity in the brain while thinking, listening to sounds or watching a video.
Everyone in the study also had an MRI scan, which uses magnetic fields to get detailed picture of the brain, and measure any shrinkage of the memory centres. Finally, people took part in memory tests, to look at memory, language, vision and other cognitive skills through paper-and-pencil and computerised tests.
Together, these gave a rich insight into brain activity and structure. This allowed us to use different types of scientific analysis to see what changes happen to the brain in people with Alzheimer's compared with healthy people of the same age.