Social isolation was associated with a 43 percent higher risk of first-time heart attack, when age, sex, and ethnicity were factored in.But when behavioral, psychological, health and socioeconomic factors were added into the mix, these factors accounted for most (84%) of the increased risk, and the initial association was no longer significant.Similarly, social isolation was initially associated with a 39 percent heightened risk of a first-time stroke, but the other conventional risk factors accounted for 83 percent of this risk.
Similar results were observed for loneliness and risk of first-time heart attack or stroke.But this was not the case for those with pre-existing cardiovascular disease among whom social isolation was initially associated with a 50 percent heightened risk of death. Although this halved when all the other known factors were considered, it was still 25 percent higher.Similarly, social isolation was associated with a 32 percent heightened risk of death even after all the other conventional factors had been accounted for.
And the size and representative nature of the study prompted the authors to conclude that their findings “indicate that social isolation, similarly to other risk factors such as depression, can be regarded as a risk factor for poor prognosis of individuals with cardiovascular disease.”This is important, they emphasise, as around a quarter of all strokes are recurrent, and targeting treatment of conventional risk factors among the lonely and isolated might help stave off further heart attacks and strokes, they suggest.
This is an observational study so no firm conclusions can be drawn about cause and effect, but the findings echo those of other research in the field, say the study authors.Future studies are needed to investigate whether interventions targeting loneliness and social isolation can help to prevent two of the leading causes of death and disability in high-income countries.