The effects of losing a spouse extend far beyond intimacy, companionship and everyday support for older adults. In fact, widowhood can accelerate cognitive decline, especially among people at risk for Alzheimer’s disease, suggests a new study published in JAMA Network Open by investigators from Brigham and Women’s Hospital and Massachusetts General Hospital in Boston.

For the inquiry, researchers classified 257 cognitively unimpaired adults ages 62 to 89 into the following groups: married, widowed or unmarried (divorced, single, separated or never married). Of 153 women and 104 men, 66 women and 77 men were married, and 31 women and four men were widowed.

At the start of the investigation, scientists measured participants’ beta-amyloid levels, a marker of Alzheimer’s disease. Each year for four years, researchers evaluated participants’ cognitive performances using a series of tests to assess various dimensions of cognition.

Findings revealed that widows had the most significant decline in cognitive performance, compared with married folks. In addition, scientists noted that among adults with the highest beta-amyloid levels, widows’ cognition waned at a rate three times faster than that experienced by married people. (No difference was found between those who were married and unmarried.)

“We know that social relationships can be an important buffer against cognitive decline,” said Nancy Donovan, MD, of the Division of Geriatric Psychiatry at Brigham and an associate researcher at Mass General. “Being married provides opportunity for more social engagement and emotional support from a spouse, it expands one’s social network, and it provides more opportunity for cognitive stimulation.”

Losing a spouse “is a highly stressful life event which can have deleterious effects on the brain,” she explained.

Donovan said her department wants to learn how widowhood affects people physiologically so researchers can create interventions to arrest cognitive impairment in this particularly vulnerable group.

For related coverage, read “Why Women Bear the Burden of Alzheimer’s,” “Should Seniors Be Screened Annually for Memory Problems?” and “Number of Older Adults with Alzheimer’s and Related Dementias to Double by 2060.”