Changes in personality during middle age are usually chalked up to a midlife crisis, but recent research has identified particular shifts that could actually be a warning sign of dementiaup to two decades before an official diagnosis.

It's already known that dementiatriggers behavioural and psychological transformations in the condition's advanced phases. Whilst midlife depression has previously been connected to heightened dementia risk, researchers from University College London sought to determine which depression symptoms showed the strongest correlation with dementia.

After publishing findings from their 23-year investigation in the Lancet Psychiatry journal, the scientists identified six midlife depression symptoms that were "robustly associated with increased dementia risk".

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These personality changes are:

• Losing confidence in myself


• Not able to face up to my problems


• Not feeling warmth and affection for others


• Nervous and strung-up all the time


• Not satisfied with the way tasks are carried out


• Difficulties concentrating

These warning signs carried the same dementia risk as recognised risk factors such as hearing loss and alcohol consumption. The six symptoms also "fully accounted" for the connection between midlife depression and dementia risk amongst those who displayed these signs before reaching 60 years of age.

The researchers stated in the study: "Our findings suggest that not all depressive symptoms contribute equally to dementia risk. Focusing on specific symptom patterns rather than treating depression as a single, unitary construct could improve early identification of individuals at increased risk of dementia and inform targeted prevention strategies."

Further investigation is required to determine whether these results can be replicated across larger and more varied populations. The research team hopes that, should their conclusions be confirmed, dementia could be identified sooner through regular screening for these particular symptoms.

Gill Livingston, a professor of psychiatry at University College London and one of the study's authors, told the Telegraphshe'd witnessed these personality shifts in her own clinical practice as a psychiatrist.

She described one instance where a "conventional" woman suddenly felt her husband was not adventurous enough for her and wanted to go out more without him. She was subsequently diagnosed with frontotemporal dementia.

This type of dementia is recognised for having a substantial impact on personality and emotional state. The NHSnotes that numerous individuals with this condition will experience behavioural changes such as heightened agitation, depressive symptoms, anxiety, wandering, aggression, or occasionally hallucinations as the illness advances.

According to Alzheimer's Society, dementia can also intensify pre-existing character traits or behaviours. The specialists noted: "For example, if the person has always been impatient or anxious, they may be even more so now that they have dementia."

As the condition advances, further personality shifts may emerge as the individual responds to feelings of fear or frustration whilst struggling with additional symptoms such as memory loss and communication difficulties.