Middle age stress may increase dementia risk

1^st October 2013 - Coping with a lot of stress in middle age may increase the risk of developing dementia in later life - at least among women.

Research published in the online journal BMJ Open suggests a woman's response to common life events, such as divorce or the death of a close family member, may trigger long lasting physiological changes in the brain.

In a statement, Dr Doug Brown, director of research and development at the Alzheimer’s Society says: "This study is not the first to link stress with the development of dementia. However, it is still unclear whether stress is a cause of the condition or exacerbates the symptoms."

Swedish study

The authors of the study base their findings on 800 Swedish women whose mental health and wellbeing were formally tracked over a period of almost 40 years as part of a larger project which started in 1968.

The women, who were born in 1914, 1918, 1922 or 1930, underwent a battery of neuropsychiatric tests and examinations in 1968, when they were in their late 30s, mid 40s, and 50s, and then were tested again in 1974, 1980, 1992, 2000 and 2005.

At their initial assessment the women were quizzed about the psychological impact on them of 18 common stressors, such as divorce, widowhood, serious illness or death of a child, mental illness or alcoholism in a close family member, personal or partner’s unemployment, and poor social support.

Also noted at every assessment were how many symptoms of distress, such as irritability, fear and sleep disturbances were reported, and how often the women had experienced them in the previous 5 years.

Findings

At the start of the study, 25% of the women had experienced at least one stressful event; 23% had experienced at least two, 20% three stressful events and 16% four or more. The most commonly reported stressful incident was mental illness in a close family member.

During the monitoring period, 425 of the women died (at the average age of 79). Between1968 and 2006, 153 women developed dementia, 104 of whom were diagnosed with Alzheimer’s disease.

The authors say their analysis showed that the number of stressful events reported in 1968 was associated with a higher incidence of dementia.

The findings held true even after taking into account factors likely to influence the results, including a family history of mental health problems.

Stress

The authors emphasise that further research is needed to confirm the findings and also to investigate if interventions such as stress management and behavioural therapy should be given to individuals who have experienced psychosocial stress.

Dr Doug Brown says: "We all go through stressful events at some stage in our lives. Understanding how these events may become a risk factor for the development of Alzheimer's disease is key to helping us find ways of preventing or treating the condition. This is an important area of research and one that we are currently supporting. It’s hoped the results of our study, and others, will offer clues to new treatments or better ways of managing Alzheimer’s."