Higher risk of dementia for middle-aged people living alone
By Kate Morley - 03/07/2009
Middle-aged people living alone have twice the risk of developing dementia and Alzheimer’s disease in later life compared with married or cohabiting people - while being widowed or divorced in mid-life carries three times the risk, according to a study led by Miia Kivipelto from the Swedish medical university Karolinska Institutet and published on bmj.com today (3 July).
As life expectancy increases in various regions of the world, dementia is becoming a growing public health concern. In 2005 an estimated 25 million people had dementia, and the number is expected to reach 81.1 million in 2040.
While there have been a number of previous studies linking good health and longevity to relationship status, this is one of the first studies to focus on mid-life marital status and the risk of dementia.
The study focused on a random sample of 2,000 men and women from Eastern Finland who took part in the cardiovascular Risk Factors, Ageing and Dementia study. Individuals were initially surveyed at around 50 years of age and again around 21 years later. Participants were divided into the following groups: married/cohabitant, single, divorced or widowed. The team also investigated whether there was a link between living alone and being a carrier of any known genetic risk factor for Alzheimer’s disease.
The results reveal that people living without a partner during middle age had a much higher risk of developing cognitive impairment in late life compared to those living with a partner. Individuals who are widowed at this age are three times more likely to develop dementia. The study also concludes that carriers of the specific gene which increases risk of Alzheimer’s who lose their partners and remain living alone have the highest risk of developing Alzheimer’s disease.
The authors say these results are important for preventing dementia and cognitive impairment and that “supportive intervention for individuals who have lost a partner might be a promising strategy in preventive health care.” The results also add to a growing body of evidence for the general importance of social factors in sustaining healthy brain functioning, they conclude.
This study adds weight to the theory that the development of cognitive impairment and dementia is a long process that is affected by various factors throughout life, writes researcher and epidemiologist Catherine Helmer. She believes that to understand the link between marital status and dementia, future research should focus on the stress caused by a separation and satisfaction with relationships. She also suggests that the findings could lead to preventive strategies that encourage unmarried, especially widowed, people to increase their social engagement by taking part in cultural, social, and sporting activities.
Rebecca Wood, Chief Executive of the Alzheimer’s Research Trust, said: “Living with a partner creates a socially and intellectually stimulating environment, protecting against cognitive impairment later in life.
“This adds weight to the ‘cognitive reserve’ hypothesis, and the notion that regular social interactions help reduce dementia risk. In societies where divorce and separation are growing trends, we need to examine how we help people adjust to living alone. Those who are widowed are at a much higher risk, and interventions soon after their loss may have a significant preventive effect.
“30 million people worldwide live with dementia, and much more research is needed if we are to defeat this dreadful condition.”
You can read the BMJ article in full by following the link below.