PET scans have shown that widowhood could boost Alzheimer's risks, according to a study by researchers from Brigham and Women's Hospital and Massachusetts General Hospital, published in the journal JAMA Network Open.

“Cognitively unimpaired, widowed older adults were particularly susceptible to Alzheimer's disease clinical progression,” the study concluded, calling widowhood “an understudied risk.”

Being married tends to further social engagement and emotional support, both known cognitive-decline fighters, according to senior author Dr. Nancy Donovan, of the Division of Geriatric Psychiatry at the Brigham and Women's Hospital, adding that beyond the loss of the social and emotional connections, the “loss of a spouse is a highly stressful life event which can have deleterious effects on the brain.”

The study used PET scans to measure β-amyloid levels in 260 cognitively unimpaired adults ages 62 to 89 — 153 women and 107 men — separated into married, widowed and unmarried groups.

No difference was found in brain functioning of the married and unmarried, but widows had more cognitive decline regardless of other factors such as age, socioeconomics or mental status — “being widowed was associated with accelerated β-amyloid–related cognitive decline during 3 years,” the study found.

The research suggests that the physiological impact of widowhood warrants further investigation.

“Our findings also suggest that researchers engaged in Alzheimer's disease prevention trials may want to pay particular attention to widowed older adults to tailor interventions for this especially susceptible group of patients,” advised the researchers.

PET scans used for Alzheimer's diagnosis were in the news in late January, when Alzheimer's researchers and patient advocates gathered in Washington for a briefing in support passage of the Medicare Diagnostic Radiopharmaceutical Payment Equity Act of 2019, also known as H.R. 3772, which would expand patient access to amyloid PET imaging for diagnosing, researching and treating Alzheimer's.

The briefing was hosted by the Medical Imaging and Technology Alliance (MITA), along with the Council on Radionuclides and Radiopharmaceuticals Inc. (CORAR), and the Society of Nuclear Medicine and Molecular Imaging (SNMMI).

Geri Taylor, a healthcare executive with Alzheimer's, who advocates for increased participation in Alzheimer's clinical trials, spoke about participating in a clinical trial for the drug Biogen, after a confirmed diagnosis with an amyloid PET scan.

"When the PET results were positive, I knew definitively I had Alzheimer's," Geri Taylor, a healthcare executive with Alzheimer's and advocate for greater Alzheimer's drug trials participation, explained, noting that, “the daily uncertainty of my life was resolved. Only individuals with positive PET scans were admitted to clinical trials. Before, they were admitted only based on symptoms. We now know the results of older trials were corrupted by participants who didn't actually have the disease.”

This latest study is not the only one to look at the links between married status and dementia risk. In 2018, a meta-analysis by U.K. and European researchers of 15 studies, published in the British Medical Journal, found that “being married is associated with reduced risk of dementia [compared with] widowed and lifelong single people, who are also underdiagnosed in routine clinical practice,” as noted by first author Dr. Andrew Summerlad of the University College London Division of Psychiatry, adding that, “dementia prevention in unmarried people should focus on education and physical health, and should consider the possible effect of social engagement as a modifiable risk factor.”