Social isolation and loneliness were associated with about a 30% increased risk of heart attack or stroke, or death from either, according to a scientific statement.
Reviewers reported research on social isolation published through July 2021 to examine the relationship between social isolation and cardiovascular and brain health. Their findings were reported as an American Heart Association scientific statement, published Aug. 4 by the Journal of the American Heart Association.
The scientific statement reported that:
- Social isolation and loneliness are common-yet-underrecognized determinants of cardiovascular and brain health;
- Lack of social connection is associated with increased risk of premature death from all causes, especially among men;
- Isolation and loneliness are associated with elevated inflammatory markers, and individuals who are less socially connected are more likely to experience physiological symptoms of chronic stress;
- The relationship between social isolation and its risk factors goes both ways. Depression may lead to social isolation, and social isolation may raise the likelihood of experiencing depression.
- Social isolation during childhood is associated with increased cardiovascular risk factors in adulthood, such as obesity, high blood pressure and increased blood glucose levels.
The scientific statement found that social isolation and loneliness were associated with a 32% increased risk of incident stroke after adjusting for age, sex, and socioeconomic position in a meta-analysis of eight longitudinal observational studies. It also reported that a multiracial and multiethnic population-based study found that socially isolated (<3 versus ≥3 social connections) adults had a 40% increased risk of recurrent stroke, myocardial infarction, or mortality when adjusted for age, race and ethnicity, atrial fibrillation, and requiring help at home.
Social isolation and loneliness were also associated lower levels of self-reported physical activity, less fruit and vegetable intake, and more sedentary time. Many large studies found significant associations between loneliness and a higher likelihood of smoking, the statement said. Socioenvironmental factors, including transportation, living arrangements, dissatisfaction with family relationships, the pandemic and natural disasters, are also factors that affect social connections.
The statement noted that more research is needed to understand how social isolation effects cardiovascular and brain health in children and young adults; under-represented racial and ethnic groups; lesbian, gay, bisexual, transgender and queer individuals; people with physical disabilities; people with hearing or vision impairments; those living in rural areas and under-resourced communities; individuals with limited access to technology and internet service; recent immigrants; and incarcerated individuals.
“Despite the breadth of literature for cardiovascular outcomes, data on the association between social isolation and loneliness and various cardiovascular and brain health outcomes are mixed but suggest that social isolation and loneliness increase risk for and worsen outcomes in cardiovascular and brain health,” according to the scientific statement. “Even where associations were found, after adjusting for factors that are presumed to be on the causal pathway, the effect sizes are on the order of 1 to 1.5, which is comparable to recognized psychosocial factors, including depression and anxiety.”