Frontotemporal dementia patients missing out on timely diagnosis and treatment, researchers say
There is no cure for frontotemporal dementia, but some symptoms can be managed with supportive care. (Supplied: University of Sydney)
In short:
Australian researchers say diagnostic guidelines for one of the most common forms of younger-onset dementia are overly restrictive and risk delaying access to treatment and clinical trials.
Behavioural variant frontotemporal dementia primarily targets parts of the brain which govern personality and social behaviour.
What's next?
Current guidelines, which exclude patients with memory loss, should be broadened, and modified to include additional criteria that capture changes in "social cognition", experts say.
Australians with one of the most common forms of younger-onset dementia may be missing out on a timely diagnosis and access to treatment because of "overly restrictive" guidelines.
That's according to researchers, who recently undertook the most comprehensive review of diagnostic criteria for behavioural-variant frontotemporal dementia (bvFTD), which mostly affects people aged 45 to 65.
It is similar to another type of frontotemporal dementia called primary progressive aphasia, which actor Bruce Willis was diagnosed with, and affects a person's ability to communicate.
Lead author Olivier Piguet said current bvFTD guidelines risked delaying diagnosis and treatment, and in some cases, could cause patients to be misdiagnosed with psychiatric or other neurodegenerative diseases, including Alzheimer's disease.
"They will carry around an incorrect diagnosis potentially for months or years and not get access to appropriate treatments and resources that would help them live the best possible life with the disease," Professor Piguet, from the University of Sydney Brain and Mind Centre, said.
The research undertaken by Professor Piguet and his colleagues, published in Alzheimer's & Dementia, found current bvFTD guidelines excluded many patients "who clearly have this form of dementia", Professor Piguet said.
The neurodegenerative disease is characterised by changes in behaviour and personality, as well as cognitive deficits, which most commonly affect executive function (such as planning and decision making) and social cognition (how we process and understand social situations).
"In Australia, there are about 30,000 people living with younger-onset dementia and … probably half will be diagnosed with bvFTD," Professor Piguet said.
'I watched my husband change'
Julane Bowen first started to notice changes in her husband Jeff's personality when he was in his early 60s, a few years before he retired as an international pilot.
"Everybody would have told you he was a social butterfly, the life of the party, very intelligent, well-read … and he was very athletic," she said.
When she raised her concerns with Jeff's GP about her husband becoming increasingly lethargic and apathetic, she said the doctor put it down to ageing, retirement, and mental health concerns.
"I was watching my husband change like Jekyll and Hyde before my eyes.
"I couldn't understand it and his doctor wasn't giving me any answers."
Julane Bowen became a dementia and mental health law advocate after her husband Jeff was diagnosed with behavioural variant frontotemporal dementia.
A few years later, Jeff retired, and soon after, began to "nosedive".
He ended up being admitted to a public psychiatric ward, following a distressing interaction with police, where he was eventually diagnosed with bvFTD.
"I had never heard of frontotemporal dementia but when I saw my husband's brain scan, I came home and googled it," Julane said.
"I am reading the signs and symptoms and thinking, 'Oh my god — he ticked every single box but one'. I couldn't understand how the doctors could not actually see it."
Frontotemporal dementia symptoms
To be diagnosed with bvFTD, a person must exhibit at least three of six "core features" or symptoms. These include: disinhibition (when someone behaves inappropriately), apathy, loss of sympathy/empathy, compulsive behaviours, and impaired cognitive function.
"[The diagnostic criteria] were designed to try to be really specific to the disease, and not other forms of dementia," Professor Piguet said.
As a result, people who have impaired cognitive function but who also have problems with episodic memory or visuo-spatial skills (which may be signs of other neurodegenerative diseases) are ruled out from having bvFTD.
People with behavioural-variant frontotemporal dementia experience changes in their personality and behaviour. (Lindsay Dunbar: ABC Graphics)
But Professor Piguet said the study demonstrated what had become "increasingly apparent" in clinical practice — that many people with bvFTD who have cognitive problems can also have difficulty with their memory or interpreting visual information.
"There were a lot of patients [in the study] who were showing executive deficits but also memory problems and visual perception problems … clearly outlining the limitations of the current diagnostic criteria."
Using data from 110 patients over 14 years, the University of Sydney researchers found nearly 90 per cent of patients presented with apathy or empathy loss, while just one in six patients met the criterion for cognitive dysfunction.
When the researchers relaxed the definition of cognitive dysfunction (so that memory and visuo-spatial difficulties didn't disqualify someone), the number of qualifying patients rose from 14.5 per cent to 73 per cent.
Professor Piguet said the research showed that behavioural symptoms were "far more consistent and reliable" indicators for bvFTD than current cognitive benchmarks.
The researchers recommended diagnostic criteria be relaxed — so the requirement for preserved memory and visuo-spatial skills is removed — and proposed adding social cognition as a core feature, noting a "breakdown in social functioning" is an early and prominent feature of bvFTD.
"At the moment, this is not measured at all, despite the fact we know this is something most carers and family members will report when you talk to them," Professor Piguet said.
"There's a mismatch between the behaviour and the social situation … it's not part of the diagnostic criteria, which is a real gap in my view."
The study also found the number, or combination, of symptoms people presented with was not a significant predictor of survival, which was found to be about 10 years on average (from symptom onset).
But Professor Piguet acknowledged that that more research was needed to be undertaken with different, more diverse population groups before changes to the guidelines were made, given the study's population was relatively small and drawn from a single specialised dementia clinic in Sydney.
"It's important to combine datasets from other [research] groups who work on these disorders in Europe, the UK and USA."
Understanding social changes and symptoms of psychiatric diseases
Matthew Kiernan, a Sydney-based neurologist and chief executive of Neuroscience Research Australia, agreed that current bvFTD guidelines could lead to delays in diagnosis and misdiagnosis.
"The good thing about this is that it is promoting discussion, and also trying to shift information across disciplines [from neuropsychology to neurology]."
Professor Kiernan, who was not involved in the research, said updating diagnostic guidelines required further research and discussion to explore the condition from both "pathological" and "behavioural, neuropsychiatric" perspectives.
"They need to bring all stakeholders together … to incorporate all of those avenues into simple criteria that your run-of-the-mill clinician, whether that's a neurologist or geriatrician, can incorporate in their assessments."
But refining diagnostic criteria would be challenging for bvFTD, he said, especially when it came to measuring social function.
Samantha Loi, a neuropsychiatrist at Royal Melbourne Hospital, said the addition of social cognition as a "core feature" would likely require patients to undergo further neuropsychological tests.
Dr Loi, who was not involved in the study, agreed that current diagnostic criteria could be overly restrictive, and said more work was needed to differentiate bvFTD from psychiatric conditions.
"bvFTD is the most common type of dementia that overlaps with psychiatric conditions," Dr Loi, an associate professor at the University of Melbourne, said.
"If they were to make new criteria, I think adding some biomarkers to differentiate that really difficult clinical conundrum … is important."
The importance of early diagnosis
While there is no cure or disease-modifying drugs available for bvFTD, Professor Piguet said diagnosing the condition accurately and early created a larger window for intervention and support.
"It's not that the person is being difficult — it's a manifestation of the disease because of where the changes are in the brain,"he said.
"[Supportive care] helps people adjust to these these difficulties, gives them strategies to minimise the severity [symptoms], which also means that it improves the quality of life of the person with the disease but also a family members."
Eight years after being diagnosed with bvFTD, and long after he was expected to survive, Jeff continues to live at home and be cared for by Julane.
In addition to regular physio and a strict diet, he's on medication to help him regulate his mood, stay awake during the day, and sleep better at night.
"He is living a quiet, happy life — he knows all of our grandchildren, he sees family every week. I think by comparison to most, we've been very lucky," Julane says.
But she said an earlier diagnosis would have prevented a significant amount of trauma.
"Early diagnosis can very much change the trajectory in the experience of the family," she said.
"Once we finally got a diagnosis and were able to get him home and put these things in place, he was able to start to settle down to what is his new normal.
"To see this [study] that might actually change how medical practitioners consider what's wrong with the patient and how they treat them … I'm very excited for this."