麻豆传媒

Social isolation has been found to be an independent mortality risk factor after a first-time cardiovascular event, according to a large-scale, observational U.K. study.

For those with a history of acute myocardial infarction (AMI) or stroke, the risk of mortality associated with social isolation was elevated 1.25-fold (95% CI 1.03 to 1.51) after full adjustment for other risk factors.

Loneliness, though, was not significantly associated with mortality in the study, Christian Hakulinen, PhD, of the University of Helsinki, Finland, and colleagues Heart.

Socially-isolated individuals and those who reported being lonely were both at significantly-elevated risk for incident AMI (HR 1.43 and 1.49, respectively) and for incident stroke (HR 1.39 and 1.36) in the model adjusted for age, sex, and ethnicity. "Most of this risk was explained by conventional risk factors," the researchers noted, as the associations with risk of events attenuated to nonsignificance in the fully-adjusted model.

Based on their analysis of the U.K. Biobank, which may be the largest study to address isolation and loneliness in this setting, Hakulinen and colleagues argued for greater attention to social isolation and loneliness.

They suggested that "guidance on how to address health risks associated with social isolation and loneliness could be added to the education of healthcare professionals, to promote prevention and treatment of cardiovascular disease in individuals with poor social connections."

Furthermore, the study authors emphasized that "around one-fourth of strokes are recurrent, and social isolation before stroke has been shown to predict poorer outcomes after stroke. However, our results showed that social isolation is associated with increased risk of mortality after AMI or stroke event, indicating that social isolation is associated with poorer prognosis."

Calling the study data "robust," invited commentator Amir Afkhami, MD, PhD, of George Washington University, Washington D.C., wrote that it "reinforces the importance of considering the social determinants of health in the overall healthcare plan for patients by physicians; particularly patients with added risk factors such as coronary artery disease."

"These studies show that there are very real morbidity and mortality repercussions and added healthcare costs of ignoring the social needs of an increasingly aging population in the United States by our policymakers in Washington."

A total of 502,632 participants ages 40 to 69 were recruited to the U.K. Biobank study from April 2007 to December 2012, and their health was followed for 7 years.

Baseline biological, behavioral, socioeconomic, psychological and health-related predictors including BMI, diastolic and systolic blood pressure, grip strength, alcohol consumption, physical activity, smoking history, education, household income, mental health, and history of chronic illness were taken into account at study entry.

Both socially-isolated and lonely persons had an increased prevalence of chronic disease and current smoking. Lonely individuals reported more depressive symptoms.

Social isolation was based on household size, frequency of visits with friends or family, and leisure or social activities engaged in once a week or more. Loneliness was measured based on self-reported feelings of loneliness and how often one is able to confide in a close confidant.

Nine percent of participants met the criteria for social isolation, 6% were deemed lonely, and 1% met the criteria for both.

Social isolation and loneliness were not significant independent predictors of stroke or AMI incidence.

Sensitivity analysis revealed consistent results across three age groups and two ethnic groups. However, a slightly stronger association between social isolation and loneliness and AMI and stroke was found in women.

Limitations to the study included that social isolation and loneliness were measured in "a very simple way," the possibility of residual confounding, and lack of generalizable results outside the age range studied.

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