A 10-year Dutch study has found that your blues could be a precursor to dementia, with 21 per cent of respondents who had severe depression later developing the condition.
Researchers from the Erasmus Medical Center in the Netherlands conducted a population study of 3325 people aged 55 and over, between 1993 and 2004, to examine possible links between depression and dementia. The results showed that 21 per cent of participants, whose depression increased over time, were eventually diagnosed with dementia, compared with the 10 per cent who reported low symptoms of depression.
The study abstract, published in The Lancet in April, surmised that signs of depression may be an early indicator of dementia developing in the brain before the more obvious signs of memory loss. Inflammation was also present in episodes of both depression and cognitive decline.
“Depressive symptoms that gradually increase over time appear to better predict dementia later in life than other trajectories of depressive symptoms,” said study co-author Dr M. Arfan Ikram. “There are a number of potential explanations, including that depression and dementia may both be symptoms of a common underlying cause, or that increasing depressive symptoms are on the starting end of the dementia continuum for older adults.”
However, the research hasn’t established the nature of the relationship – which one is the cause and which is the symptom?
A study from July 2014 found similar results. More than 1700 people, with an average age of 77, began the study with no cognitive or memory problems. They were screened every year for eight years, looking for symptoms of depression and loneliness, and had their thinking and memory skills tested. During the study, about half of the participants developed mild cognitive and memory problems – a total of 315, or 18 per cent, were diagnosed with dementia.
The researchers established that high levels of depression before a dementia diagnosis were linked to a drastic decline in cognitive and memory function, however, the onset of dementia did not seem to cause an increase in depression.
Read more at Generations Healthcare.
Do you think better understanding of depression treatment is necessary, particularly among the ageing population?