Few people would consider loneliness a positive condition. Many come to know its unfortunate mental toll at some time or other during the course of their lives—but medicine is increasingly recognizing the physical toll it takes, too, especially when it becomes long-term.
In a study published today in the journal eClinicalMedicine, researchers from the Harvard T. H. Chan School of Public Health found a link between chronic loneliness and an increased risk of stroke for older adults, adding to the growing body of work on the health implications of loneliness. Using data from a 12-year period starting in 2006, they looked at how adults over the age of 50 had reported feelings of loneliness over time. Those who suffered most from the feeling also experienced a 56 percent greater risk of having a stroke, a significant difference.
Those who faced situational, or more temporary loneliness did not see the same increase in risk, which helped the researchers realize the danger was more likely chronic feelings of isolation. They emphasized that an individual’s perception itself matters, more than any concrete measure of participants’ “social isolation,” such as their number of friends.
Yenee Soh, the lead author of the study and a research associate in the department of social and behavioral sciences, called for targeted interventions to combat the problem of loneliness, which she said is “increasingly considered a major public health issue.”
In fact, the researchers’ finding comes amid a moment of national alarm about loneliness. (Read the Harvard Magazine feature article, “The Loneliness Pandemic,” for more.) U.S. Surgeon General Vivek Murthy ’98 declared the problem a national epidemic last year, writing in a New York Times op-ed that “the increased risk of premature death associated with social disconnection is comparable to smoking daily—and may be even greater than the risk associated with obesity.” He issued a report that detailed a dramatic drop in the amount of time Americans spent with friends during the pandemic, particularly young people.
The surgeon general’s report also called for a collective effort to increase connectedness using everything from more in-person work to medical training for doctors to recognize loneliness as a health risk.
Prior studies have found associations between loneliness and cardiovascular diseases, but the research of Soh and colleagues Loeb professor of social epidemiology Ichiro Kawachi, professor of social and behavioral sciences Laura D. Kubzansky, Cabot professor of public policy and epidemiology Lisa F. Berkman, and Feldberg professor of maternal and child health Henning Tiemeier adds new insight to that work by looking at loneliness’s connection to stroke risk over many years, with strokes considered “one of the leading causes of long-term disability and mortality worldwide,” according to the study.
The researchers relied on a 20-question survey called the UCLA Revised Loneliness Scale, which asks respondents to rate the frequency of experiences such as feeling left out or isolated. It included more than 12,000 participants and checked in with them during the course of several years to see how their feelings of loneliness had changed. Then, controlling for known stroke risk factors, the scientists compared survey responses to instances of strokes, leading to the study’s principal conclusion that the mental perception of loneliness and physical risk of stroke are indeed connected.
The study does not explain why or how strokes might be connected to chronic loneliness, although current literature suggests it may in part lead to greater inflammation and poorer immune health, higher consumption of tobacco and alcohol, reduced quality of sleep, and other unhealthy behaviors.
Kubzansky, a coauthor, said that it fit into a larger debate about the role of mental health in determining physical health, which some prominent health institutions have been reluctant to recognize outright. “Mental health really is a contributor to downstream physical health,” she said.
As the national focus on loneliness and its serious health implications prompt a search for solutions, Kubzansky cautioned that simply telling vulnerable people to socialize more (by phoning a family member or organizing meet-ups, for example) would not be adequate. She called for a focus on the “structural factors” causing loneliness on a societal level. That way, the burden of the problem doesn’t fall entirely on individuals and the doctors treating them. “There may be barriers,” she said, “that are simply not in people’s hands to manage.”
