Moderate to severe mid-life anxiety may be linked to dementia in later life, according to new research published in the journal BMJ Open.
Mental illness may be associated with dementia in older age, however it is still not clear if it represents an initial advent of symptoms before the disease develops or if it acts as an independent risk factor.
The researchers analysed four studies involving 30,000 participants, which looked at the association between mid-life anxiety, in isolation or combined with depression, and the development of dementia.
All of the studies accounted for a range of potentially influential demographic, physical, and psychological factors, and all found an association between moderate to severe anxiety and future dementia, with a gap of at least 10 years in between diagnoses.
The studies were all of high quality, strengthening the findings, the researchers say.
The findings back up recent evidence pointing to a link between anxiety and risk of mild cognitive impairment, and lend weight to the known association between depression and dementia.
An abnormal stress response, which is typical of moderate to severe anxiety, may speed up brain cell ageing and degenerative changes in the central nervous system, so increasing vulnerability to dementia, they suggest.
‘Whether reducing anxiety in middle age would result in reduced risk of dementia remains an open question. Non-pharmacological therapies, including talking therapies and mindfulness-based interventions and meditation practices, that are known to reduce anxiety in midlife, could have a risk reducing effect, although this is yet to be thoroughly researched,’ the researchers say.