Widowhood accelerates dementia among those at risk, say researchers from Brigham and Women’s Hospital and Massachusetts General Hospital.

Once widowed, cognitively normal participants in the Harvard Aging Brain Study experienced a sharper decline in mental abilities when compared to their married peers, reported lead investigator Nancy Donovan, M.D. The decline was greatest – three times faster – among study participants with high amyloid beta levels, an established marker of dementia, she reported. Meanwhile, there was no difference between study participants in the married group and the unmarried group.

The loss of a spouse is a highly stressful life event which can have deleterious effects on the brain, said Donovan, a geriatric psychiatrist. In contrast, the social relationships offered by marriage provide a buffer against cognitive decline, offering opportunities for more social engagement, emotional support and cognitive stimulation, she said.

“All of these benefits are lost in widowhood,” she said.

The study, published in JAMA Network Open, is the first to link widowhood and amyloid beta to cognitive decline, according to the researchers.