Social isolation, loneliness increase risk of heart attack, stroke - study

Social isolation and loneliness are common, but under-recognized determinants of cardiovascular and brain health.

Organs in the body - transparent illustration (photo credit: American Heart Association)
Organs in the body - transparent illustration
(photo credit: American Heart Association)

Social isolation and loneliness (SI/L) can increase your risk of suffering a heart attack or stroke by about 30%, according to a new peer-reviewed research article by the American Heart Association published on Thursday.

Social isolation is defined as having “few or infrequent social contacts,” according to the article, while loneliness is defined as “perceived isolation that is distressing for the individual.” While the two are related, they are distinct, operate through different pathways and have unique downstream effects on health.

The risk of SI increases with age, as the elderly tend to be left alone due to factors such as widowhood and retirement. Nearly a quarter of US adults 65 years old and older are socially isolated, and between 22% and 47% are lonely.

SI/L also increased during the coronavirus pandemic as people were stuck in lockdown and social distancing.

The writing group behind the article reviewed research on social isolation through July 2021 to examine its relationship with cardiovascular and brain health.

 Crystal Wiley Cené, M.D., M.P.H., FAHA, Professor of Clinical Medicine, Chief Administrative Officer for Health Equity, Diversity and Inclusion, University of California San Diego Health (credit: University of California San Diego Health) Crystal Wiley Cené, M.D., M.P.H., FAHA, Professor of Clinical Medicine, Chief Administrative Officer for Health Equity, Diversity and Inclusion, University of California San Diego Health (credit: University of California San Diego Health)

The scientists found that SI/L are common, but under-recognized determinants of cardiovascular and brain health. They also found a link between a lack of social connection and increased risk of premature death from all causes, especially among men.

Individuals who were less socially connected were also found to be more likely to experience the physiological symptoms of chronic stress. Social isolation during childhood is associated with increased cardiovascular risk factors in adulthood, including obesity, high blood pressure and increased blood glucose levels, according to the article.

“Given the prevalence of social disconnectedness across the US, the public health impact is quite significant.”

Crystal Wiley Cené, M.D., M.P.H., FAHA, chair of the writing group for the scientific statement

“Over four decades of research has clearly demonstrated that social isolation and loneliness are both associated with adverse health outcomes,” said Crystal Wiley Cené, M.D., M.P.H., FAHA, chair of the writing group for the scientific statement, and professor of clinical medicine and chief administrative officer for health equity, diversity and inclusion at University of California San Diego Health. “Given the prevalence of social disconnectedness across the US, the public health impact is quite significant.”

Social isolation and loneliness raises risk of death by heart attack and stroke

According to the article, social isolation and loneliness are associated with a 29% increase in the risk of death by heart attack and/or heart disease and a 32% increase in the risk of death by stroke.

THE PROGNOSIS of heart disease and stroke patients is also negatively impacted by SI/L, with socially isolated people with heart disease having a two- to three-fold increase in death during a six-year follow-up study.

Socially isolated adults with three or fewer social contacts per month could have a 40% increased risk of recurrent stroke or heart attack. And five-year heart-failure survival rates were lower for people who were socially isolated (60%) and for those who are both socially isolated and clinically depressed (62%), compared to those who have more social contacts and are not depressed (79%).

While findings suggest an increased risk of worse outcomes among heart disease and stroke patients who are socially isolated or lonely, these studies “do not suggest causality, and associations may be mediated by other factors that need to be further tested,” the article stressed.

“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,” Cené said.

More research and work needed

The chair of the writing group stressed that there is an “urgent need” to develop, implement and evaluate programs and strategies to reduce the effects of SI/L on cardiovascular and brain health.

“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,” she said. “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.”

The writing group did not find any research aimed at reducing social isolation with the specific goal of improving cardiovascular health. Cené stressed that it is unclear whether being or feeling isolated matters most for cardiovascular and brain health, as there are only a few studies that have examined both at once.

“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.”