A journal published recently suggested that dementia may result from moderate to severe anxiety in midlife. Amy Gimson, a researcher at the University of Southampton’s Faculty of Medicine in the United Kingdom led a team of scientists in this research and observed a link between mental health problems and late-onset dementia. They noted that the risk of Alzheimer is doubled by depression which is often accompanied by anxiety. Although, there have been reports of anxiety symptoms in people who were later diagnosed of dementia, it is however unclear whether anxiety and depression present as indicators of dementia or whether they are independent risk factors.
Depression has been identified as one risk factor for dementia, and anxiety frequently co-occurs with depression and is a relatively prevalent disorder.
Most of the previous studies have investigated this association during the 5 to 10 years before dementia diagnosis. These studies do not present with high accuracy because the average length of prodromal preclinical cognitive decline is approximately 5 to 6 years, and mild cognitive impairment (MCI) may progress to Alzheimer’s disease (AD) within 5 years. Therefore, a more accurate way of determining the dependence of dementia prodrome on anxiety would be an analysis of studies where there was an interval of at least a 10 years between anxiety assessment and diagnosis of dementia.
The findings of the meta-analysis of Gimson and her team involved 3,500 studies encompassing about 30,000 people recruited from either the community, hospital inpatient/outpatient populations, or both and were published in the journal BMJ Open.
So, they attempted to find the link between midlife depression, with or without anxiety, and late-onset dementia and found a positive correlation between anxiety of moderate to severe levels and the later development of dementia, therefore suggesting that anxiety could be an independent risk factor for late-onset dementia.
In this research, they included studies that had an average of at least a 10-year time interval between the assessment of anxiety and diagnosis of dementia to minimize the likelihood that anxiety was an early sign of dementia.
The results showed a “significant increase” in the number of dementia diagnoses in patients who either had a diagnosis of anxiety or who experienced clinically significant anxiety symptoms ≥10 years prior to their being diagnosed with dementia. They concluded that there is a relationship between midlife moderate to severe anxiety and risk of dementia.
The authors note that the longer interval between anxiety and dementia diagnosis “may provide evidence for a common biological pathway linking anxiety, depression, and dementia.”
Therefore, it can be noted that brain changes may present initially as midlife anxiety or depression, and eventually manifest as dementia symptoms. Anxiety and depression might be predictive, but the influence of other risk factors remain unknown and whether treating them would reduce the risk is also unclear. The researchers however stated that suggesting routine screening for people with dementia in middle aged adults with anxiety might not have a strong basis for now.