Last updated March 27, 2018 at 5:06 pm
New study suggests other risk factors loom larger.
Research has highlighted links between loneliness and social isolation, and death from heart disease or stroke but a new observational study suggests this is only an independent risk factor for people with pre-existing heart conditions.
Other known risk factors still largely explain links observed between loneliness/social isolation and first time heart disease/stroke, the researchers say.
Their work drew on data from nearly 480,000 people aged 40 to 69 who were part of the UK Biobank study between 2007 and 2010.
Underlying long term conditions
Participants provided detailed information about their ethnic background, educational attainment, household income, lifestyle (smoking, drinking, exercise) and depressive symptoms. Height, weight and grip strength were measured and blood samples taken.
In all, 9 per cent of respondents were deemed to be socially isolated, 6 per cent lonely, and 1 per cent both. Those in these groups were more likely to have other underlying long term conditions and to be smokers, while those who were lonely also reported more depressive symptoms.
Over a seven-year monitoring period, 12,478 people died, 5731 people had a first heart attack and 3471 suffered a first stroke.
Social isolation was associated with a 43 per cent higher risk of first-time heart attack when age, sex, and ethnicity were factored in, but when behavioural, psychological, health and socioeconomic factors were added they accounted for 84% of the increased risk and the initial association was no longer significant.
Similarly, social isolation was initially associated with a 39 per cent heightened risk of a first-time stroke, but the other conventional risk factors accounted for 83 per cent of this risk.
First time heart attack
Similar results were observed for loneliness and risk of first time heart attack or stroke.
However, this was not the case for those with pre-existing cardiovascular disease, among whom social isolation was initially associated with a 50 per cent heightened risk of death. Although this halved when all other known factors were considered, it was still 25 per cent higher.
Similarly, social isolation was associated with a 32 per cent heightened risk of death even after all the other conventional factors had been accounted for.
The size and representative nature of the study prompt 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 say, 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.
The paper was published in Heart.