Singles at greater Alzheimer's risk, study says

A new study finds unmarried middle-aged people are more likely to develop cognitive impairment than their partnered counterparts.

In the study of partnered and non-partnered people, scientists examined almost 1,500 people who were questioned in midlife and then again 21 years later. Almost 10 percent of those in the study were diagnosed with some form of cognitive impairment. Forty-eight had Alzheimer's disease.

Those who lived with a partner in midlife were less likely to be cognitively impaired than all the others.