Delays in the diagnosis of dementia and a failure to make the most of existing resources remain major concerns for patients, families, carers and health professionals, even as research into treatments and interventions progresses, say the authors of an editorial published online by the Medical Journal of Australia.

Dr Terence Chong and his co-authors Dr Samantha Loi, Prof. Nicola Lautenschlager and Prof. David Ames from the Academic Unit for Psychiatry of Old Age at the University of Melbourne and NorthWestern Mental Health, part of Melbourne Health, detailed recent advances in dementia research, particularly in the area of Alzheimer's disease (AD).

"The introduction of the federal government-funded, state-based Dementia Behaviour Management Advisory Services, the initiation of severe behaviour response teams, and increased funding for research should be applauded, but there needs to be greater coordination of service delivery systems for patients and carers at every stage, from prevention through to end-of-life care, and the medical profession needs to do more to ensure that all existing and trainee practitioners are well informed about what we can do for people with dementia right now," Chong and his colleagues wrote.

"In 2015, there were an estimated 47 million people with dementia worldwide (including 343 000 in Australia), a number that will double every 20 years to 131 million by 2050 (900 000 in Australia). The global cost of dementia in 2015 was estimated to be US$818 billion."

AD is the most common form of dementia in Australia, affecting 50-70% of all dementia patients, followed by vascular dementia (10-20%), dementia with Lewy bodies (10%), and fronto-temporal dementia (4%).

Chong and his co-authors said there were drugs licensed for the treatment of AD that had "modest but measurable benefits for some patients".

"More than 200 other drugs advanced to at least Phase II development between 1984 and 2014, but none has yet entered routine clinical use," they wrote.

"Lack of efficacy in clinical trials may be the result of their being introduced at a rather late stage of the disease process; hippocampal damage is so profound by the time that individuals present with AD dementia that attempting to slow their decline with an anti-amyloid agent may be analogous to starting statins in patients on a heart transplantation waiting list."

The identification of risk factors was also a pathway to risk reduction strategies, Chong et al commented.

"Greater risk reduction might be attained by intervening 10 to 20 years before the first clinical signs of cognitive impairment are presented. Such interventions [including dietary, exercise, cognitive training and vascular risk-monitoring components] could improve or maintain cognition in at-risk older people in the general population."