Feeling depressed for long periods without receiving treatment creates degenerative changes to the brain, making sufferers more susceptible to dementia later in life, new research has revealed.
Leading Australian mental health expert Graham Burrows has told an international psychiatry conference that neuro-imaging techniques and animal studies had shown that the emotional response of depression made physical changes to the brain.
“We now know that depression is probably a neuro-degenerative disorder like Alzheimer’s disease,” said professor Burrows, director of psychiatry at the University of Melbourne.
“When you have an emotional response, it’s a chemical process.
“What started as a psychological thing becomes a physical thing.”
Professor Burrows said dementia, of which Alzheimer’s disease makes up 60 per cent of cases, is set to become Australia’s second biggest medical burden after heart disease – within a decade.
He told the International Congress of Biological Psychiatry in Sydney that 11 to 17 per cent of patients with Alzheimer’s disease also suffered depression.
Some studies of dementia had shown a rate of depression as high as 50 per cent.
“If you take the demented person, probably 14 per cent of them have significant depression at that point in time… because of the chemical changes that have occurred in the brain.”
While many people suffering depression go untreated, Professor Burrows said even when people were treated it was often inadequate. Withholding or delaying treatment would result in more damage to the brain.
“If you’ve got depression it must be vigorously, actively treated, and the duration of the treatment must be significantly longer then what we’ve been doing in medicine until relatively recently.”
As Australia’s population ages, rates of dementia will reach epidemic proportions: by 2040, 2.3 per cent of the population will have the disease.
Professor Burrows said dementia cost the community $6.6 billion in 2002, and by 2050, the cost of dementia would equal 3 per cent of gross domestic product.
He said there was an urgent need for resources to cope with the burden dementia would place on health services in the future.
Young people could possibly prevent dementia by doing regular exercise to increase endorphins, stress management, and keeping mentally active, he said.