Currently, 70,000 New Zealanders have dementia. That's set to rise to 170,000 by 2050.
Auckland psychiatrist Dr Etuini Ma'u is the co-author of a University of Auckland study that shows the potential for reducing rates of dementia by targetting common risk factors in middle-aged New Zealanders.
It's a misconception that dementia is a disease of the elderly, Dr Ma'u says.
While the symptoms manifest in older age, in the 20 years before there are incremental changes occurring in the brain of a person who will develop dementia.
There are twelve modifiable risk factors for dementia, as highlighted in a 2020 Lancet Commission report: less education (i.e. not completing high school) hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, low social contact, excessive alcohol consumption, traumatic brain injury, and air pollution.
The University of Auckland study also looked at the prevalence of these risk factors across different ethnicitiesities in New Zealand - and found they differed between ethnic groups, Dr Ma'u says.
To be effective, any government dementia prevention strategy would have to be tailored to target New Zealand's ethnic groups specifically.
"For example, in Pacific Island groups, because the cardiovascular risk factors are so much higher potentially, that's where the targets need to be. But in Europeans, depression and social isolation are coming up with the strongest link, on top of hearing loss."
The study's findings are a great starting point for discussion about how New Zealand can target dementia risk factors and reduce dementia prevalence.
"It's a really simple message to get out there - anything that is good for your heart is good for your mind."
Dr Etuini Ma'u is a consultant psychiatrist at Waikato Hospital and a senior lecturer in Psychological Medicine at the University of Auckland.