Loneliness can increase the risk of stroke by up to 56%, research shows

Loneliness can increase the risk of stroke by as much as 56%, according to research that experts say explains why the problem is a major health threat worldwide.

The World Health Organization (WHO) has said that loneliness is one of the most important global health problems, affecting every facet of health, well-being and development. The US Surgeon General has warned that its mortality effects are equivalent to smoking 15 cigarettes a day.

Although previous research has linked loneliness to a higher risk of developing cardiovascular disease, few have specifically examined its impact on stroke risk. The study, led by Harvard University, is the first of its kind to examine the association between changes in loneliness and stroke risk over time.

Researchers found that adults aged 50 and older who experienced chronic loneliness had a 56% higher risk of stroke than those who consistently reported not being lonely.

Those who experienced situational loneliness but did not suffer from it long-term did not have a higher risk of stroke, the study found. This suggests that the impact of loneliness on stroke occurs over many years.

The lead author, Dr. Yenee Soh, research associate at Harvard TH Chan School of Public Health, said: “Loneliness is increasingly considered a major public health problem. Our findings further highlight why this is so.

“Especially when experienced chronically, our study suggests that loneliness may play an important role in the incidence of stroke, which is already one of the leading causes of long-term disability and death worldwide.”

The findings have been published in eClinicalMedicine.

The study used data from the University of Michigan Health and Retirement Survey from 2006 to 2018. More than 12,000 people aged 50 and over who have never had a stroke were asked questions about loneliness between 2006 and 2008.

Four years later, about 9,000 people who remained in the study responded to the same questions, and researchers then grouped them based on their answers at the two time points.

The groups were “consistently low” (those who scored low on both points on the loneliness scale); ‘remitting’ (those who scored high at baseline and low at follow-up); “recent onset” (those who scored low at baseline and scored high at follow-up); and “consistently high” (those who scored high at both baseline and follow-up).

After controlling for factors like social isolation and depressive symptoms, which are closely related to loneliness but different, researchers found that people who were considered lonely at the start of the study had a 25% higher risk of stroke than those who were not considered lonely.

But among those who scored ‘consistently high’ on loneliness at both time points, there was a 56% higher risk of stroke than those in the ‘consistently low’ group.

“Repeated assessments of loneliness can help identify people who are chronically lonely and therefore at greater risk of stroke,” says Soh.

People should be offered help based on their loneliness – which relates to how people feel even when surrounded by others – and not on the basis of social isolation, which is different, Soh added.

“If we fail to address their feelings of loneliness, on a micro and macro scale, there can be profound health consequences.”