Living with Alzheimer’s disease – a global challenge
Diagnoses of dementia, of which Alzheimer’s disease is the most common form, are becoming increasingly common due to an ageing population. At Monash University, clinical trials involving a non-invasive form of treatment is showing some promising signs in managing the condition so that people living with dementia can lead fulfilling lives.
More than 46 million people worldwide have some form of dementia. Alzheimer’s disease, estimated to affect around 70 per cent of all people with dementia, is a progressive degeneration of brain cells. While the exact cause of Alzheimer’s disease is unknown, it results in an abnormal build-up of a protein called amyloid beta. This causes the formation of ‘plaques’ outside the brain cells, while inside the brain cells, another protein, called tau , builds up into ‘tangles’. This abnormal accumulation of proteins within the brain damage and disrupt the connections between brain cells, eventually resulting in brain cell death.
At Monash Alfred Psychiatric Research Centre (MAPrc), Transcranial Magnetic Stimulation (TMS) is being trialled in patients. The process involves placing a hand-held figure of eight shaped coil over the region of the brain to be stimulated. Magnetic pluses are applied through the coil, these pass freely into the brain and cause the underlying neurons to become active. TMS takes around 12 minutes, and is given when people are wide awake, and seated comfortably in a chair.
Principal investigator on this project, Associate Professor Kate Hoy, said there were some promising signs in the early data from the trial which still had a number of years to run.
“In a person living with Alzheimer’s, by stimulating the brain daily using TMS for a number of weeks, we get the brain cells ‘firing’ which increases their activity. Eventually this leads to stronger connections and communication throughout the brain. What we are hoping for is an improvement in cognition following active treatment, and over time, perhaps a slowing of the progression of the illness.
“When TMS is given daily over a number of weeks, brain activity shows lasting changes: both where the stimulation was applied but also in connected brain regions. This occurs because as TMS causes neurones to fire repeatedly this strengthens their connections, essentially helping neurones to 'talk to each other'.”
Associate Professor Hoy said the Monash study differed from the small number of previous clinical trials of TMS for Alzheimer’s, which had shown only a small to moderate improvements in cognition.
“The type of TMS we are applying, called theta burst stimulation, will allow us to give full treatment doses to all four brain regions we are targeting every treatment session. Theta burst stimulation provides TMS pluses in a pattern that is more consistent with the brain’s natural firing pattern and so can deliver essentially a full treatment dose in much shorter time,” she said.
In Australia, without a significant medical breakthrough, more than 6.4 million people will be diagnosed with dementia in the next 40 years. This will come at a cost of more than $1 trillion, according to Alzheimer’s Australia.
Symptoms of Alzheimer’s vary, and may be very subtle in the early stages of the disease. There is also no one definitive test for diagnosis. This can be challenging and time-consuming when making a diagnosis.
Some of the symptoms may include:
- Persistent and frequent memory loss
- Language difficulties
- Becoming disoriented, even in places that are well known
- Taking longer to complete routine tasks
- Difficulty or inability to process and act upon questions or instructions
- Changes in behaviour, personality and mood.