SAN DIEGO — Loneliness increases the risk of cardiovascular disease by almost a third, according to new research. Socially isolated individuals are about 30 percent more likely to suffer a stroke or heart attack — death from either.
Scientists at the University of California, San Diego also identified a lack of information on interventions that may boost the health of vulnerable individuals. The findings are based on data pooled from studies across the world over the past 40 years.
“Over four decades of research has clearly demonstrated social isolation and loneliness are both associated with adverse health outcomes,” says lead author Dr. Crystal Wiley Cené, a professor of clinical medicine and chief administrative officer for health equity, diversity and inclusion at the school, in a statement. “Given the prevalence of social disconnectedness across the U.S., the public health impact is quite significant.”
Risk increases with age due to life factors, such as widowhood and retirement. But the problem is increasingly affecting young people. The study finds social isolation and and loneliness increase the risk of death from heart disease or stroke by 29 and 32 percent, respectively.
“Social isolation and loneliness are also associated with worse prognosis in individuals who already have coronary heart disease or stroke,” says Cené.
People with heart disease who were socially isolated had a two to threefold increase in death during a six-year follow-up study. Socially isolated adults with three or fewer social contacts a month were up to 40 percent more likely to suffer recurrent strokes or heart attacks. In addition, five year heart failure survival rates were 60 and 62 percent lower for those who were socially isolated or both socially isolated and clinically depressed, respectively.
In the U.S., almost a quarter of over 65s are socially isolated, with prevalence of loneliness rising to nearly half. A Harvard University study describes 18 to 22 year olds, or “Gen Z,” as the “loneliest generation.” Increased isolation among younger adults has been blamed on higher social media use and less engagement in meaningful face to face activities.
Pandemic of loneliness?
Data also suggests loneliness increased during the pandemic. Young adults aged 18 to 25, older adults, women and low-income individuals were most affected.
Social isolation is defined as having infrequent in-person contact with people for social relationships, such as with family, friends or members of the same community or religious group. Loneliness is when you feel like you are alone or have less connection with others than you desire.
“Although social isolation and feeling lonely are related, they are not the same thing,” explains Cené. “Individuals can lead a relatively isolated life and not feel lonely, and conversely, people with many social contacts may still experience loneliness.”
The study shows that both conditions are common, yet under-recognized factors in cardiovascular and brain disease. Lack of social connection is linked to increased risk of premature death from all causes, especially among men.
Isolation and loneliness are associated with elevated inflammatory markers, increasing symptoms of chronic stress. It becomes a vicious circle. Depression may lead to social isolation, and social isolation may increase the likelihood of experiencing depression. Social isolation during childhood can even lead to cardiovascular disease in adulthood, increasing the risk of obesity, high blood pressure and raised blood glucose levels.
Socio-environmental factors, including transportation, living arrangements, dissatisfaction with family relationships, the pandemic and natural disasters, are also factors that affect social connections. “There is strong evidence linking social isolation and loneliness with increased risk of worse heart and brain health in general; however, the data on the association with certain outcomes, such as heart failure, dementia and cognitive impairment is sparse,” says Cené.
‘Urge need to develop, implement, and evaluate programs and strategies’
Social isolation and loneliness are also associated with behaviors that negatively impact cardiovascular and brain health. These include lower levels of self-reported physical activity, less fruit and vegetable intake, and more sedentary time. Multiple large studies found significant associations between loneliness and a higher likelihood of smoking.
“There is an urgent need to develop, implement and evaluate programs and strategies to reduce the negative effects of social isolation and loneliness on cardiovascular and brain health, particularly for at-risk populations,” adds says Cené. “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. They should then be prepared to refer people who are socially isolated or lonely – especially those with a history of heart disease or stroke – to community resources to help them connect with others.”
Some populations are more vulnerable to social isolation and loneliness such as children and young adults and those from racial and ethnic minority groups. Others include the disabled, those living in rural and under-resourced communities, people with limited access to technology and internet service, recent immigrants and incarcerated individuals and LBGTQ individuals.
Research among older adults shows fitness programs and recreational activities at senior centers, as well as addressing negative thoughts of self-worth and other negative thinking, are promising interventions.
“It is unclear whether actually being isolated (social isolation) or feeling isolated (loneliness) matters most for cardiovascular and brain health because only a few studies have examined both in the same sample,” says Cené. “More research is needed to examine the associations among social isolation, loneliness, coronary heart disease, stroke, dementia and cognitive impairment, and to better understand the mechanisms by which social isolation and loneliness influence cardiovascular and brain health outcomes.”
The study is published in the Journal of the American Heart Association.
Report by South West News Service writer Mark Waghorn.