A new study has found that elderly persons who lived alone in middle-age had twice the risk of developing dementia and Alzheimer’s disease compared with people who were married or cohabited in middle-age.
The study also found that elderly persons who were widowed or divorced in mid-life had a three-time risk of dementia.
While there have been a number of studies linking being in a couple to good health and longevity, this is one of the first studies to focus on mid-life marital status and the risk of dementia for later life.
In the study, researchers based in Finland and Sweden interviewed a random sample of 2,000 men and women who took part in the cardiovascular Risk Factors, Ageing and Dementia study. The participants came from two regions in eastern Finland.
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 the apolipoprotein E e4 gene variant (or allele), the 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 apolipoprotein E e4 gene variant 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 healthcare’.
These results also add to a growing body of evidence for the general importance of social factors in sustaining healthy brain functioning, they concluded.
This study strengthens the hypothesis that the development of cognitive impairment and dementia is a long process that is affected by various factors throughout life, according to the French researcher and epidemiologist, Dr Catherine Helmer.
Writing in an accompanying editorial, Dr Helmer commented 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 suggested 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.
BMJ Online, available at: http://www.bmj.com/cgi/doi/10.1136/bmj.b2462