Living alone makes people more likely to develop Alzheimer’s disease in later years of life, said a Swedish study, presented on Wednesday at the International Conference on Alzheimer's Disease at McCormick Place, Chicago, Illinois. The study reported that people in their 40’s and 50’s who lived alone were 50% more likely to develop Alzheimer’s two decades later.

This was especially true for those people who were widowed and never remarried and divorced people. The researchers also discovered that the risk of developing dementia was affected by factors such as how long a person lived alone and under what circumstances they did so.

The study found that those who lived alone for their entire adult lives faced twice the risk for dementia while those who divorced in middle age and remained single had three times the risk of dementia. The highest risk for dementia was in those who were not yet middle aged when their partner died and lived alone afterward with a dementia risk that was six times that of married couples in the study.

Lead researcher, Krister Håkansson of Vaxjo University and the Karolinska Institute in Sweden, said, "This suggests two influencing factors -- social and intellectual stimulation and trauma. In practice, it shows how important it is to put resources into helping people who have undergone a crisis. If our interpretation will hold, such an intervention strategy could also be profitable for society considering the costs for dementia care."

Researchers feel frequent social interaction delays the cognitive decline which is associated with Alzheimer's disease. Other factors that different studies have found to contribute to Alzheimer’s are the presence of the ApoE gene, the use of psychotropic drugs as well as being a smoker. Another study has shown that people who give more thought to their problems are less likely to develop Alzheimer's.

Dr. Raj Shah, medical director of the Rush Memory Clinic in Chicago, said, "We can't do much with the genetics. But if we can encourage people to do things that might improve ... traits that would put them at risk, it would help."