Social isolation is a substantial risk factor for dementia in older adults, according to a pair of studies that add evidence to past research on this threat.
But these new studies offer a potential solution: using technology to encourage older adults to text and email to stay in touch.
Although the studies don't prove lack of regular social contact causes dementia, researchers said they do strengthen observations that isolation increases the risk. They suggested that relatively simple steps to increase social support may reduce that risk.
About 1 in 4 people over age 65 in the United States is socially isolated.
"Social connections matter for our cognitive health, and it is potentially easily modifiable for older adults without the use of medication," said Dr. Thomas Cudjoe, senior author of both studies. He's an assistant professor of medicine at Johns Hopkins University School of Medicine in Baltimore.
The first study used data collected on more than 5,000 Medicare beneficiaries for a long-term study of health and aging trends that began in 2011. Participants were asked to complete an annual two-hour, in-person interview to assess their mental functioning, health status and overall well-being.
About 23% reported social isolation at the start. They showed no signs of dementia.
After nine years, 21% of participants had developed dementia. And the risk was 27% higher among socially isolated older adults, researchers found.
"Socially isolated older adults have smaller social networks, live alone and have limited participation in social activities," said study co-author Alison Huang, a senior research associate at Johns Hopkins Bloomberg School of Public Health. "One possible explanation is that having fewer opportunities to socialize with others decreases cognitive engagement as well, potentially contributing to increased risk of dementia."
In the other study, researchers found that communications technology, such as telephones and email, lowered the risk for social isolation.
To research this, they used data from participants in the same nationwide health and aging study. They found that more than 70% of seniors who were not socially isolated at their initial appointment had a working cellphone and/or computer.
Those participants regularly used email or texting to communicate with others. Adults who had consistent access to technology had a 31% lower risk for social isolation than the others.
"This study shows that access and use of simple technologies are important factors that protect older adults against social isolation, which is associated with significant health risks," said Dr. Mfon Umoh, a postdoctoral fellow in geriatric medicine who led the technology study. "This is encouraging, because it means simple interventions may be meaningful."
More work is needed to identify people at risk and to create tools to minimize that risk, researchers said. Future research should focus on risks based on biological sex, physical limitations, race and income level, they noted.
The studies were recently published in the Journal of the American Geriatrics Society.