Loneliness can literally take a toll on the heart according to a new scientific statement, and researchers have found that social isolation was associated in numerous studies with an increased risk of heart attack and stroke, among other adverse health outcomes.
The statement, published Thursday in the Journal of the American Heart Association, evaluated all available scientific literature on social isolation in the context of cardiovascular and brain health to provide a broad picture of what the research points to.
The researchers noted that since this is a review of a large number of studies, the aim was not to test or address a specific research question, but rather to summarize the scope and nature of the studies.
“More than four decades of research has clearly shown that social isolation and loneliness are associated with adverse health outcomes,” said Dr. Crystal Wiley Cené, chair of the scientific statement writing group and professor of clinical medicine at the University of California San Diego Health, he said in a press release. “Given the prevalence of social disengagement in the US, the public health impact is quite significant.”
The statement indicated that the risk of social isolation increases as we age, with a quarter of American adults over the age of 65 reporting isolation. The prevalence of loneliness in this cohort ranges from 22 to 47 percent.
But loneliness is also on the rise in younger adults according to other studies, according to the release, which appears to align with numerous reports of increased loneliness during the pandemic.
Cené clarified that social isolation and loneliness refer to measures of two different things.
“Although social isolation and loneliness are related, they are not the same,” explains Cené. “People can lead relatively isolated lives and not feel lonely and, conversely, people with many social contacts can still experience loneliness.”
To compile the statement, the researchers reviewed the relevant scientific literature through July 2021, searching four databases: PubMed, PsycInfo, Cumulative Index of Nursing and Allied Health, and Scopus.
Overall, they found that the body of research points to social isolation and loneliness as common determinants of cardiovascular and brain health.
Some other main points that kept resurfacing were that a lack of social connections is associated with an increased risk of premature death, particularly among men, and that social isolation during childhood was associated with higher levels of risk factors for cardiovascular problems in Adulthood.
However, the connection of social isolation and loneliness with specific cardiovascular and brain outcomes was less certain.
“There is strong evidence linking social isolation and loneliness with an increased risk of poorer heart and brain health in general; however, data on the association with certain outcomes, such as heart failure, dementia, and cognitive decline, are scarce,” Cené said.
The clearest associations in the literature were between social isolation/loneliness and the risk of death from heart disease and stroke.
The researchers say there was a 29 percent increased risk of heart attack or death from heart disease, and a 32 percent increased risk of stroke and death from stroke among those who reported social isolation or loneliness.
“Social isolation and loneliness are also associated with a worse prognosis in people who already have coronary heart disease or stroke,” Cené added.
For many specific outcomes, the data was inconsistent.
For example, in 19 previous studies, the researchers found that in 16 of them, social isolation increased the risk of incident coronary heart disease. In the remaining three, loneliness was associated with increased risk.
But a recent large-scale study from 2021 found that social isolation, measured in that study by looking at whether they lived alone and how often they had contact with friends, family, or participated in groups, was not associated with incident CHD.
Another review found that patients with existing coronary artery disease were 2 to 3 times more likely to die within six months of follow-up if they were socially isolated.
There was limited data to paint a clear picture of whether social isolation or loneliness played a role in heart failure, according to the researchers. However, in terms of survival rates after heart failure, the researchers stated that the five-year survival rate was lower among people who were socially isolated and clinically depressed compared with people without those. problems, with a survival rate of 60 percent compared to 79 percent, respectively.
No studies have yet focused on the connections between social isolation, loneliness, and vascular dementia that researchers might find.
The researchers also looked at how the body of research accounted for depression, which is often studied alongside social isolation and loneliness. They said most research found it was a feedback loop, with loneliness and isolation capable of causing depression, and depression capable of exacerbating loneliness and isolation.
Although the body of research as a whole contains less specificity about certain health outcomes, the researchers say it’s clear we need to take social isolation and loneliness more seriously as a risk factor.
“Clinicians should ask patients about the frequency of their social activity and whether they are satisfied with their level of interactions with friends and family,” Cene said. “Then they should be prepared to refer socially isolated or lonely people, especially those with a history of heart disease or stroke, to community resources to help them connect with others.”
He noted that we don’t know if there is a measurable difference in clinical outcomes between those who are truly socially isolated, such as being physically alone with little connection to others by phone or Internet, and those who perceive themselves to be socially isolated.
“Further research is needed to examine the associations between social isolation, loneliness, coronary heart disease, stroke, dementia, and cognitive decline, and to better understand the mechanisms by which social isolation and loneliness influence outcomes.” cardiovascular and brain health outcomes,” he said.